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Pollard, Simon J. T. « Low-cost adsorbents from industrial wastes ». Thesis, Imperial College London, 1990. http://hdl.handle.net/10044/1/8387.
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Madiraju, Saisantosh Vamshi Harsha. « COLOR REMOVAL AND TREATMENT OF DYE AND SUGAR WASTE WATER USING LOW COST ADSORBENTS ». Cleveland State University / OhioLINK, 2018. http://rave.ohiolink.edu/etdc/view?acc_num=csu1530272885958543.
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Melo, Diego de Quadros. « LIGNOCELLULOSIC ACTIVATED WASTE USE ADSORBENTS IN TOXIC METALS IONS REMOVAL : BATCH AND COLUMN STUDIES USING DESING EXPERIMENTAL ». Universidade Federal do CearÃ, 2015. http://www.teses.ufc.br/tde_busca/arquivo.php?codArquivo=17236.
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FundaÃÃo Cearense de Apoio ao Desenvolvimento Cientifico e TecnolÃgicoThe tururi and buriti fibers, and the castor bean stalks are extremely efficient to sorption of metal ions from aqueous solutions. In this study, the adsorbents were activated with different concentrations of alkali solutions (5, 7, 10 and 15% w/v). The materials were characterized by analytical techniques as infrared, X-ray Diffraction (XRD) and Thermogravimetry analysis. The infrared spectra revealed that associated groups to macromolecules of hemicellulose and lignin after alkaline activation have less intensity compared to the initial samples. The XRD revealed, that after castor bean stalks alkaline activation, the presence of the cellulose type II peaks, which did not occur with tururi and buriti fibers. The fluorescence X-ray data showed that the cations present in the initial adsorbents, K+ and Ca2 + are exchanged by Cu (II), Ni (II), Cd (II) and Pb (II) in the sorption process. Studies of the influences of variables: mass of adsorbent; agitation rate; the initial pH and concentration using a fractional factorial design 24-1 demonstrated that all variables affect the response (adsorption capacity mg g-1). As a result for a larger value of qtotal, conditions were observed while maintaining the pH at 5.5; mass of the adsorbent 50 mg; agitation at 200 rpm and the initial concentration: 500 mg L-1. The adsorption kinetics revealed fast adsorption process, about 30 minutes, and good fitting to pseudo-second-order theoretical model to all adsorption process studied. Intraparticle diffusion models as Weber-Morris and Boyd were testes in order to study the limiting steps of the process.The results showed that for tururi and buriti fibers (with the exception of nickel ions) the rate-limiting step is not the intraparticle diffusion, while for the castor bean stalks, it was found that the rate-limiting step of the process is the intraparticle diffusion. The study of monoelement and multielement systems were performed at pH 5.5, initial concentrations from 20-500 mg L-1, which the experimental data were fitted to the Langmuir, Freundlich and Sips theoretical models. The tururi fibers adsorption capacities (mg g-1) in monoelementar and multielement system follows the order Pb (188.79)> Cd (92.20)> Cu (32.82)> Ni (22.23) and Cd (77.53)> Pb (43.93)> Cu (24.99)> Ni (19.51), respectively. Buriti fibers adsorption capacities (g-1 mg) in monoelementar and multielement systems follows the order of Cu (143.1)> Pb (112.1)> Ni (103.7)> Cd (86.33) and Pb (69.12)> Cu (49.28)> Ni (45.10)> Cd (24.95), respectively. Castor bean stalks adsorption capacities (g-1 mg) in in monoelementar and multielement systems follows the order of Pb (175.1)> Cd (124.8)> Ni (111.1)> Cu (89.23) and Cu (56.78)> Pb (55.82)> Cd (44.72)> Ni (43.48), respectively. The results showed a better fit for the Sips model, relating to a heterogeneous adsorption. Fixed bed studies using castor bean stalks checking the influence of variables adsorbent flow (1, 2 and 3 mL min-1), the height of the column (5, 7 and 10 cm) and initial concentration (100 , 200, 300 mg L-1) by the Box-Behnken planning revealed that there were no influence between the variables in the studied. The breakthrough curves were well fitted to the Thomas model. The study in real effluent with Cu (II) (galvanoplastic sector) was carried out using the optimized condition: flow (1 ml min-1); bed height (10 cm) initial concentration: (245.5 mg L-1) and it was found adsorption capacity of 32.42 mg g-1. The mamoneira stalks adsorbent was used for five cycles to verify their potential reuse, and it was found no significant efficiency losses.
As fibras tururi, buriti e talos da mamoneira sÃo resÃduos lignocelulÃsicos extremamente eficientes na sorÃÃo de metais de soluÃÃes aquosas. Neste trabalho, eles foram ativados com diferentes concentraÃÃes de soluÃÃes alcalinas (5, 7, 10 e 15% m/v). Os materiais foram caracterizados pelas tÃcnicas analÃticas de Infravermelho, DifraÃÃo de Raios-X (DRX) e Termogravimetria. Os espectros de infravermelho revelaram que os grupos associados Ãs macromolÃculas de hemicelulose e lignina diminuem em intensidade ou desaparecem apÃs a ativaÃÃo alcalina. Os DRX revelaram que apÃs a ativaÃÃo alcalina, os talos da mamoneira apresentaram picos de celulose tipo II, o que nÃo ocorreu com as fibras de tururi e buriti. O dados de FluorescÃncia de Raios-X revelaram que os cÃtions presentes nos adsorventes como Na(I) e Ca(II) sÃo trocados pelos Ãons Cu(II), Ni(II), Cd(II) e Pb(II) no processo de sorÃÃo. Os estudos das influÃncias das variÃveis: massa do adsorvente; taxa de agitaÃÃo; pH e concentraÃÃo inicial utilizando planejamento experimental fracionÃrio 24-1 demostrou que todas as variÃveis afetaram a resposta (capacidade de adsorÃÃo mg g-1). Como resultado para um maior valor de qtotal, as condiÃÃes observadas foram mantendo o pH em 5,5; massa do adsorvente em 50 mg; taxa de agitaÃÃo em 200 rpm e concentraÃÃo inicial 500 mg L-1. A cinÃtica de adsorÃÃo revelou rÃpida adsorÃÃo, cerca de 30 minutos em geral, seguindo o modelo de pseudo-segunda ordem em todos os processos adsortivos. Modelos de difusÃo intrapartÃcula como de Webber-Morris e Boyd foram estudados a fim de determinar as etapas limitantes do processo. Os dados evidenciaram que para as fibras de tururi e buriti (com exceÃÃo dos Ãons nÃquel) a etapa limitante da velocidade nÃo à a difusÃo intraporo, enquanto para os talos de mamoneira foi verificado que a etapa limitante do processo à a difusÃo intrapartÃcula. O estudo com sistema monoelementar e multielementar foi realizado em pH 5,5, concentraÃÃes variando de 20-500 mg L-1, nos quais os dados foram aplicados aos modelos de Langmuir, Freundlich e Sips. As capacidades de adsorÃÃo (mg g-1) em sistema monoelementar e multielementar das fibras de tururi segue a ordem Pb(188,79)> Cd(92,20)> Cu(32,82)> Ni(22,23) e Cd(77,53)> Pb(43,93)> Cu(24,99)> Ni(19,51), respectivamente. As capacidades de adsorÃÃo (mg g-1) das fibras de buriti em sistema monoelementar e multielementar segue a ordem Cu(143,1)> Pb(112,1)> Ni(103,7) > Cd(86,33) e Pb(69,12)> Cu(49,28)> Ni(45,10)> Cd(24,95), respectivamente. As capacidades de adsorÃÃo (mg g-1) dos talos de mamoneira em sistema monoelementar e multielementar segue a ordem Pb(175,1)> Cd(124,8)> Ni(111,1)> Cu(89,23) e Cu(56,78)> Pb(55,82)> Cd(44,72)> Ni(43,48), respectivamente. Em geral, os resultados evidenciaram melhor aplicabilidade ao modelo de Sips, o qual prediz que os sÃtios disponÃveis para adsorÃÃo sÃo heterogÃneos. Em relaÃÃo ao estudo de adsorÃÃo em leito fixo utilizando talos de mamoneira, a verificaÃÃo da influÃncia das variÃveis: fluxo do adsorvente (1, 2 e 3mL min-1), altura da coluna (5, 7 e 10 cm) e concentraÃÃo inicial (100, 200, 300 mg L-1) pelo planejamento de Box-Behnken, revelou que nÃo hà influencia mutua entre as variÃveis no intervalo estudado. As curvas de ruptura experimentais foram bem aplicadas ao modelo teÃrico de Thomas. O estudo com efluente real de Ãons Cu (II) (setor galvanoplÃstico) utilizando a condiÃÃo otimizada: fluxo (1mL min-1); altura de leito (10 cm) e concentraÃÃo inicial: (245,5 mg L-1) obteve 32,42 mg g-1 de capacidade de adsorÃÃo O adsorvente talos de mamoneira foi utilizado por cinco ciclos para verificar seu potencial de uso, nÃo havendo perdas significativas de eficiÃncia.
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ORTIZ, NILCE. « Estudo da utilizacao de magnetita como material adsorvedor dos metais Cusup(2+), Pbsup(2+), Nisup(2+) e Cdsup(2+), em solucao ». reponame:Repositório Institucional do IPEN, 2000. http://repositorio.ipen.br:8080/xmlui/handle/123456789/10825.
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Tese (Doutoramento)
IPEN/T
Instituto de Pesquisas Energeticas e Nucleares - IPEN/CNEN-SP
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LEAL, ROBERTO. « Estudo da magnetita como material adsorvedor de íons uranilo ». reponame:Repositório Institucional do IPEN, 2006. http://repositorio.ipen.br:8080/xmlui/handle/123456789/9299.
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Dissertacao (Mestrado)
IPEN/D
Instituto de Pesquisas Energeticas e Nucleares - IPEN/CNEN-SP
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Leal, Roberto. « Estudo da magnetita como material adsorvedor de íons uranilo ». Universidade de São Paulo, 2006. http://www.teses.usp.br/teses/disponiveis/85/85134/tde-15052012-132433/.
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A magnetita, também chamada de ferrita de ferro, é um minério conhecido como imã natural e encontrada em depósitos de ferro. Além desse comportamento intrínseco, a magnetita possui a capacidade de remover os íons metálicos do meio aquoso por fenômenos de adsorção. O seu caráter fortemente magnético a distingue de outros tipos de adsorventes, visto que, é facilmente removida da solução por separação magnética. Neste trabalho estudou-se a adsorção de urânio(VI), na forma de íons UO22+, de solução nítrica pela magnetita sintética. Esta foi preparada por precipitação simultânea adicionando-se uma solução de NaOH à solução contendo os íons Fe2+ e Fe3+. A magnetita sintética, na forma de um pó preto, exibiu uma resposta magnética de atração intensa na presença de um campo magnético, sem contudo tornar-se magnética, um comportamento típico de material superparamagnético constatado por medidas de magnetização. Estudou-se a influência dos parâmetros de adsorção de íons UO22+ tais como o pH, a dose do adsorvente, tempo de contato e a isoterma de equilíbrio. A máxima adsorção de urânio foi encontrada no intervalo de pH entre 4 e 5. Verificou-se que quanto maior a dose de magnetita menor a capacidade de adsorção e maior a remoção de U. Da relação entre adsorção e tempo de contato verificou-se que a remoção aumentou rapidamente com o tempo e atingiu-se a condição de equilíbrio em 30 min. Os resultados da isoterma de equilíbrio apresentaram maior concordância com o modelo de Langmuir, o qual permitiu a determinação da capacidade teórica de saturação da magnetita para o urânio. A interação entre os íons UO22+ e a magnetita foi caracterizada como uma adsorção química e espontânea.Magnetite, also known as iron ferrite, is a mineral iron and a natural magnet found in iron deposits. In addition to its magnetic intrinsic behavior, the magnetite has the capacity to remove the metallic ions from aqueous medium by adsorption phenomena. The strong magnetic character of magnetite distinguishes it from other adsorbent types, which it allows to be readily removed from solution by magnetic separation. In this work, uranium (VI) adsorption, as UO22+ ions, from nitric solution by synthetic magnetite was investigated. It was prepared by simultaneous precipitation process, adding a NaOH solution into a solution containing Fe2+ and Fe3+ ions. The synthetic magnetite, a black powder, has exhibited a strong magnetic response in presence of a magnetic field, without nevertheless becomes magnetic. This typical superparamagnetic behavior was confirmed by magnetization measurements. Adsorption parameters of UO22+ ions such as pH. the adsorbent dose, contact time and equilibrium isotherm were evaluated. Maximum uranium adsorption was observed in the pH 4.0-5.0 range. It was noticed that increase in magnetite dose increased the percent removal of uranium, but decreased the adsorption capacity of the magnetite. It was observed from the relation between adsorption and contact time that the removal has increased very fast with time, and achieved the equilibrium within 30 minutes. The results of equilibrium isotherm agreed well with the Langmuir model, and so the theorical saturation capacity of the magnetite was determined for uranyl ions. The interaction between UO22+ ions and the magnetite was defined as a spontaneous chemical adsorption.
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Xin, Jiat Lee. « Evaluation of cost effective adsorbent and biochar from Malaysia oil palm wastes : synthesis, characterisation and optimisation studies ». Thesis, University of Nottingham, 2018. http://eprints.nottingham.ac.uk/48864/.
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The rapid development of palm oil industry in Malaysia has generated significant amount of solid and liquid wastes, contributing to major environmental issues in the past five decades. Palm oil residues such as palm kernel shell (PKS), empty fruit bunch (EFB) and palm oil sludge (POS) are difficult to be disposed of. Thus, the potential application of the oil palm wastes for synthesis of value added products such as adsorbents for heavy metals removal and solid biochars for fuel generation, are presented in this thesis. In the past three decades, industrialisation and urbanisation in Malaysia have led to an increase of heavy metals, such as copper, cadmium, lead, zinc, chromium and nickel, in the rivers and lakes. The presence of the heavy metals is causing harmful effects on the aquatic environment and human health, hence it is necessary to control the discharge of industrial effluent into the environment. Among various heavy metals abatement technologies, adsorption is by far the most promising technique due to its relatively easy operation and high efficiency. However, adsorption is associated with costly adsorbent, such as activated carbon which is usually made from non-renewable resource. This has motivated many researchers to investigate and develop cost effective adsorbents for the removal of heavy metals. In this research, biosorbent was prepared from palm oil sludge. The preparation steps were relatively simple and low cost, involving mechanical treatments such as drying, milling and sieving. The POS biosorbent was tested on removal of copper (Cu2+) and cadmium (Cd2+), followed by process optimisation using response surface methodology (RSM), based on central composite design (CCD). Comparing between one-factor-at-a-time (OFAT) and RSM-CCD methods, both studies produced results which were in good agreement. The investigation was carried out to evaluate the effects of adsorbent dosage (W), initial pH, initial concentration (C0) and contact time (t), on the heavy metals removal. From optimisation study using RSM-CCD, the optimum adsorption parameters for Cu2+ removal were as follows: W = 0.3 g; pH 4.56; C0 = 200 mg L-1; t = 60 min, with maximum adsorption capacity (q) of 15.84 mg g-1, and for Cd2+ removal were as follows: W = 0.3 g; pH 5.8; C0 = 200 mg L-1; t = 60 min, with maximum q of 18.49 mg g-1. The adsorption equilibrium of Cu2+ and Cd2+ were best described by Langmuir and Freundlich models, respectively, based on the lowest sum of normalised error (SNE). The adsorption kinetic of Cu2+ and Cd2+ were best fitted with pseudo-second-order kinetic model. Thermodynamically, the adsorption processes were spontaneous, exothermic and feasible. Regeneration of POS biosorbent was carried out using hydrochloric acid (HCl) as the eluent, and the results indicated the high desorption efficiency for Cu2+ (up to 0.98) and Cd2+ (0.95) from the biosorbent, respectively. The POS biomass was also converted to POS-char by slow pyrolysis which was subsequently used in lead (Pb2+) adsorption study. The synthesis of POS-char was optimised by RSM-CCD based on simultaneous maximisation of biochar yield and q of Pb2+. The interactive effects of nitrogen flowrate (FN2), heating rate (HR), pyrolysis temperature (Tpyro) and pyrolysis time (tpyro) on the responses were investigated. It was determined that the maximum biochar yield was 80.35 % and q was 4.11 mg g-1, formed at the following slow pyrolysis conditions: FN2 = 30 mL min-1; HR = 10 °C min-1; Tpyro = 500 °C; tpyro = 30 min. In Pb2+ adsorption study, the optimum parameters determined by RSM-CCD optimisation were as follows: W = 0.3 g, pH 3.2, C0 = 200 mg L-1 and t = 60 min, with a maximum q of 21.76 mg g-1. The adsorption equilibrium of Pb2+ was best represented by Freundlich model. This finding indicated that the sorption sites in POS-char were heterogeneous. The kinetic study revealed that at low concentrations, the kinetic of adsorption complied with pseudo-first-order model, while at high concentrations, it obeyed pseudo-second-order model. Regeneration of POS-char was successfully conducted using HCl and the adsorbent exhibited reusability up to 5 adsorption-desorption cycles, with the desorption efficiencies between 0.58 and 0.99. Beyond 3 cycles, the adsorbent showed noticeable structural damage. Overall, the adsorption of Pb2+ onto POS-char was spontaneous, exothermic and feasible. The slow pyrolysis of PKS and EFB to biochars was investigated by simultaneously varying factors such as FN2, HR, Tpyro and tpyro. The synthesis parameters were optimised by RSM-CCD with respect to multiple responses, including biochar yield, higher heating value (HHV) and energy yield. The interactive effects of FN2, HR, Tpyro and tpyro on the three responses were in good agreement with literature data. The determined optimum conditions for PKS-char and EFB-char production by slow pyrolysis were as follows: FN2 = 30 mL min-1, HR = 18.9 – 20.0 °C min-1, Tpyro = 500.0 – 504.3 °C and tpyro = 30 min. The combustion kinetic on the optimised PKS-char and EFB-char were found to possess favourable combustion characteristics such as low activation energy (Ea), high energy yield and HHV. Overall, the combustion of PKS-char and EFB-char occurred in multi-step kinetics behaviour until burnout. The cost analysis on synthesis of PKS-char, EFB-char, POS-char and POS biosorbent was performed based on independent case studies which considered the capital and operating costs. The results revealed that addition of the thermochemical conversion plant to existing oil palm mill was highly feasible. The unit cost for production of PKS-char, EFB-char, POS-char and POS were USD$ 3.94 kg-1, USD$ 1.21 kg-1, USD$ 2.17 kg-1 and USD$ 0.19 kg-1 ̧ respectively.
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Trieu, An. « Design of hybrid nano-composite adsorbent for recovery of Pd And Au from electronic wastewater ». Thesis, Lyon, 2018. http://www.theses.fr/2018LYSE1314.
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Les sources secondaires de métaux précieux, tels que les déchets électroniques, ont récemment attiré l’attention générale suite à la sensibilisation sur l’épuissement des ressources naturelles et sur l’industrie du recyclage sur l’emploi et la croissance économique. Developper des technologies de recyclage qui permettent l’extraction de palladium (Pd) et d’or (Au) en très faibles concentrations (10-100 ppm) dans les effluents électroniques s’avère aujourd’hui économiqueemnt viable.Dans ce contexte, notre étude aborde l’utilisation de nanoparticules de ZrO2 modifiées avec des ligands complexants en surface pour capturer efficacement et sélectivement des ions Pd(II) et Au(III) dan les effluents électroniques. Les avantages de l’utilisation de acide thioctique commercial (TOA) par rapport aux acides dialkyldiglycoamide ou (N, N)-dialkylcarbamoylméthylphosphoniques en termes de capacité d’adsorption et de sélectivité ont été démontrés. Des expériences d’adsorption en mode batch combinées à la méthode ICP-OES ont été réalisées et nos résultats ont montré des capacités d’adsorption envers le Pd et l’Au de 6.3 mg/g et de 43 mg/g, respectivement. Les processus d’adsorption suivaient le modèle de Langmuir et les cinétiques chimiques d’adsorption étaient mieux adaptés à l’équation du pseudo-second ordre. Les conditions d’optimisation pour la mise en place du stripping sélectif à l’aide de solutions acidifiées de thiourée ont également été étudiées. En particulier, afin d’améliorer la réutilisation de ce matériau hybride, des processus de modification des surface en deux étapes ont été développés par fonctionnalisation de la surface de nano-ZrO2 avec de l’acide alendronique et par une réaction de couplage peptidique avec du TOA.De plus, les procédés de greffage de nano-ZrO2 sur un textile en polypropylène modifié avec les groupements carboxylique ont été étudiés via des méthodes traditionnelles de revêtement par immersion (dip-coating) et de revêtement couche par couche (LbL). Cette dernière s’est avérée être une méthode prometteuse en termes de flexibilité, de facilité de manipulation et de respect de l’environnment. Les nanocomposites obtenus ont démontré d’excellentes propriétés d’adsorption de Pd et d’AuSecondary sources of precious metals, such as e-waste, have been recently gaining more attention thanks to raising awareness of natural resources depletion and sound impact of recycling industry on employment and economic growth. Recycling technologies have now to be developed, enabling extraction of very small concentration (10-100 ppm) of precious metals, such as palladium (Pd) and gold (Au), from effluents of recycling factories economically viable.In this context, our study addresses the use of thioctic surface-modified zirconia nanoparticles to capture efficiently and selectively Pd(II) and Au(III) ions from industrial electronic wastewater. The advantages of using the commercial thioctic acid (TOA) over dialkyldiglycoamide or (N,N)-dialkylcarbamoylmethylphosphonic acids ones in terms of adsorption capacity and selectivity were demonstrated. Batch-mode adsorption experiments combined with ICP-OES method were conducted and our findings have displayed adsorption capacities toward Pd and Au of 6.3 mg/g and 43.3 mg/g, respectively. The adsorption processes were found to follow the Langmuir model and adsorption rates were best-fitted to pseudo-second order equation. The optimization conditions for selective stripping set-up using acidified solutions of thiourea were also investigated. Particularly, in order to improve the reusability of this hybrid nanomaterial, two-step surface modification processes were developed through alendronic acid-surface functionalization of nano-ZrO2 and amide coupling reaction with TOA.Furthermore, the grafting processes of nano-ZrO2 onto carboxylic-modified polypropylene textile were studied via traditional dip-coating and layer-by-layer coating methods. It has been realized that layer-by-layer coating method is a promising method in terms of its flexibility, ease of handling, and environmental friendliness
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Wu, Zhibin, Xingzhong Yuan, Hua Zhong, Hou Wang, Guangming Zeng, Xiaohong Chen, Hui Wang, Lei zhang et Jianguang Shao. « Enhanced adsorptive removal of p-nitrophenol from water by aluminum metal–organic framework/reduced graphene oxide composite ». NATURE PUBLISHING GROUP, 2016. http://hdl.handle.net/10150/614746.
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In this study, the composite of aluminum metal-organic framework MIL-68(Al) and reduced graphene oxide (MA/RG) was synthesized via a one-step solvothermal method, and their performances for pnitrophenol (PNP) adsorption from aqueous solution were systematically investigated. The introduction of reduced graphene oxide (RG) into MIL-68(Al) (MA) significantly changes the morphologies of the MA and increases the surface area. The MA/RG-15% prepared at RG-to-MA mass ratio of 15% shows a PNP uptake rate 64% and 123% higher than MIL-68(Al) and reduced graphene oxide (RG), respectively. The hydrogen bond and pi-pi dispersion were considered to be the major driving force for the spontaneous and endothermic adsorption process for PNP removal. The adsorption kinetics, which was controlled by film-diffusion and intra-particle diffusion, was greatly influenced by solution pH, ionic strength, temperature and initial PNP concentration. The adsorption kinetics and isotherms can be well delineated using pseudo-second-order and Langmuir equations, respectively. The presence of phenol or isomeric nitrophenols in the solution had minimal influence on PNP adsorption by reusable MA/RG composite.
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Su, Lingcheng. « Soil contamination and plant uptake of metal pollutants released from Cu(In, Ga)Se₂ thin film solar panel and remediation using adsorbent derived from mineral waste material ». HKBU Institutional Repository, 2018. https://repository.hkbu.edu.hk/etd_oa/552.
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The Cu(In,Ga)Se2 (CIGS) thin-film solar panels (TFSPs) are widely used in integrated photovoltaic (PV) and solar power systems because of their perfect PV characteristics and ductility. However, the semiconductor layers of these panels contain potentially toxic metals. In this study, the potential environmental pollution arisen by CIGS TFSP treated as construction trash at the end of their useful life was examined. Acid extraction was used to simulate leaching toxicity followed by burying CIGS TFSP material in different soils, namely a synthetic soil, a Mollisol, and an Oxisol, to determine whether metal pollutants might be released into the soil. A vegetable, Brassica parachinensis L. H. Bariley (VegBrassica), was selected to grow in these polluted soils to investigate the uptake of metals and their bioaccumulation. The simulative remediation of contaminated soils was carried out using a remediation module created by the combination of activated carbon and modified mineral waste material (MMWM) in this research. The activated carbon derived from the waste biomass material was produced by an environmental friendly method, and the MMWM was obtained through a thermal dehydroxylation treatment. The physiochemical properties of MMWM, with focusing on mineral phase transformation, were related to the changes in surface morphology due to dehydroxylation occurred during the process of thermal treatment of MMWM samples, and the adsorption performances of metal (lead, Pb) and organic compound (methyl orange, MO) onto this newly modified MMWM were studied. Furthermore, an end-of-life treatment method was designed and proposed for harmless disposal of CIGS TFSP. Various metals, including Pb, zinc (Zn), nickel (Ni), chromium (Cr), gallium (Ga), copper (Cu), indium (In) and aluminum (Al) were found to be released into the soil and caused contamination when scrapped end-of-life CIGS TFSP were buried, and the rates of metal release changed with the variations of both the amounts of CIGS TFSP material in the soil and the soil properties. The increases in concentrations of heavy metals such as Zn, Cu, Ni, Ga, Pb, In, and Cr were correlated with the amounts of CIGS TFSP material added in soils. The Pollution Index and the Nemerow Contamination Index calculated from our results confirmed that, when buried, the CIGS TFSP material polluted the soil. Plants grew well in the synthetic soil and the Mollisol, but those in the Oxisol showed prominent signs of chlorosis and died after 30 days. The bioaccumulation factor (BF) and concentration of Zn were 3.61 and 296 mg/kg, respectively in VegBrassica grown in the synthetic soil with 10% (200 g to 2 kg of soil) of added CIGS TFSP, while the BF and concentration of In were 3.80 and 13.72 mg/kg, respectively in VegBrassica grown in the Mollisol, indicating that bioaccumulation occurred. The thermally treated MMWM samples showed morphological transformation mainly on surface based on the scanning electron microscopy (SEM) observations, and an increasing trend in BET specific surface area (SSA) from 120 to 500 ℃ followed by a decreasing trend up to 1000 ℃. Thermal modification had successfully improved Pb adsorption capacity up to 515 mg/g, corresponding to MMWM modified at 600 ℃ with an SSA of 6.5 m2/g. The MO adsorption capacity was also improved after thermal treatment of MMWM, which performed the best adsorption of 87.6 mg/g at 400 ℃. The adsorption of Pb and MO were mainly chemisorption and monolayer coverage, as pseudo-second-order model and Langmuir equation displayed good relationships of correlation for Pb and MO adsorption data. It is therefore indicated that the newly designed soil remediation modules could significantly remove metals from the contaminated soils. In summary, c
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Chkir, Mouna. « Synthèse de gels phosphocalciques issus de déchets industriels carbonatés : caractérisation physico-chimique, thermique et rhéologique ». Thesis, Toulouse, INPT, 2011. http://www.theses.fr/2010INPT0039/document.
Texte intégralRésumé :
Les travaux présentés ont pour objectif la valorisation de déchets industriels riches en carbonates pour la préparation de gels phosphocalciques. Ces gels sont destinés à des applications environnementales. Leur synthèse est basée sur la réaction des carbonates de calcium avec une solution de phosphates solubles à température ambiante et à pression atmosphérique. Le procédé élaboré à l’échelle laboratoire consiste à additionner les réactifs en variant les paramètres expérimentaux tels que le Ca/P, la température et la dilution. Cette méthode a été utilisée pour la synthèse de gels à partir de deux types de déchets industriels. Une synthèse de référence a été définie à base de carbonates de calcium purs. Dans la première partie de ce travail, une caractérisation physico-chimique et thermique des poudres synthétisées a été réalisée par différentes techniques telles que le Microscopie Electronique à Balayage (MEB), la diffraction des rayons X (XRD), la spectroscopie infrarouge à transformée de Fourier (FTIR) et la thermogravimétrie. Les résultats obtenus ont montré la formation de précurseurs de Ca-HAp qui évoluent de phosphates de calcium monocalciques à des particules de Ca-HAp amorphe. Une chronologie de cette évolution a été mise en évidence pour les carbonates de calcium purs et confirmée pour les carbonates de calcium issus des déchets industriels. La transformation des carbonates de calcium a été étudiée en réalisant un bilan massique basé sur la consommation des carbonates de calcium. Ce bilan, réalisé à température ambiante, a confirmé un taux de conversion à plus de 90% pour les carbonates de calcium purs, jusqu’à 70% des carbonates issus du premier type de déchet et 50% des carbonates correspondant au deuxième type de déchet. L’influence de certains paramètres expérimentaux s’est avérée primordiale pour l’amélioration de ce taux de conversion et particulièrement l’augmentation de la température. Dans la deuxième partie de ce travail, les propriétés rhéologiques des gels phosphocalciques ont été étudiées. Le suivi de la viscosité et des caractéristiques élastiques a permis de mettre en évidence la formation d’un gel viscoélastique qui pourrait présenter de nombreux avantages dans des applications environnementalesThe aim of this research was the valorization of industrial wastes rich in carbonates to prepare calcium phosphate gels for environmental applications. The phosphocalcic gel was prepared by precipitation from calcium carbonate industrial waste and a phosphate solution. The process consisted in mixing the reagents under a set of variable parameters (pH, Ca / P, temperature, dilution) to study the influence of each parameter on the conversion rate and the adsorption properties of the synthetized material. A reference hydroxyapatite was prepared following the same procedure with a commercial carbonate grade (98% wt), in order to compare with the waste-made hydroxyapatite. The characterization and chemical analysis of synthetized hydroxyapatites were carried out by means of rheology, particle size, Scanning Electron Microscopy, BET, ThermoGravimetric Analysis – Differential Scanning Calorimetry, X Ray Diffraction and Infrared spectroscopy (Fourrier Transformation Infra Red) analysis. The results obtained led to find out the chronology of the carbonates conversion into Ca-Hap precursors and particles of amorphous Ca-HAp. The kinetics show that the conversion rate is about 90% (wt) for pure CaCO3, 70% for the first waste and 50% for the second waste. Monitoring the viscosity and elastic properties has allowed us to demonstrate the formation of a viscoelastic gel. The synthesis of an elastic gel of calcium phosphate using CaCO3 waste seems to be a promising way to transform calcium residues into a valuable sorbent. Valorization of this gel in environmental applications for pollution remediation seems to be an advantageous perspective
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Nevena, Blagojev. « Modelovanje i optimizacija kontinualne biosorpcije jona teških metala iz vode ». Phd thesis, Univerzitet u Novom Sadu, Tehnološki fakultet Novi Sad, 2019. https://www.cris.uns.ac.rs/record.jsf?recordId=110557&source=NDLTD&language=en.
Texte intégralRésumé :
U disertaciji je ispitana mogucnost korišcenjaizluženih rezanaca šecerne repe za adsorpcijujona bakra u koloni sa nepokretnimslojem. Eksperimenti su izvedeni primenomBoks-Benkenovog eksperimentalnog dizajnana tri nivoa sa tri promenljive: koncentracijanapojnog rastvora (50-150 mgL-1), masaadsorbenta (8-12 g) i pH napojnog rastvora(4,0-5,0). Dobijene prevojne krive sufitovane uobicajenim empirijskim modelima,Boart-Adamsovim i modelom doza-odziv.Na osnovu uocene asimetrije prevojnekrive, predložen je novi matematicki model.Novi model predlaže prevojnu krivu kojase sastoji od dva dela, koji u zbiru dajukumulativnu krivu koja dosledno pokrivauocenu asimetriju. Uzimajuci u obzir najnižuprosecnu sumu kvadrata odstupanja, SSer(3,610-3) i najvišu prosecnu vrednostkoeficijenta determinacije, R2 (0,9989),novi model je pokazao najbolje fitovanjeeksperimentalnih podataka, u poreenju sauobicajeno korišcenim modelima adsorpcijeu koloni. RSM i ANN modelovanje je daljekorišceno za evaluaciju procesnih parametarai optimizaciju procesa. Najznacajnijanezavisno promenljiva velicina, koja ispoljavanegativan uticaj na odabrani odziv (kriticnovreme), bila je koncentracija napojnograstvora, dok je masa adsorbenta ispoljilaslabiji i pozitivan uticaj na odziv. Optimizacijom procesa metodom ANN jeutvreno da se najveca vrednost kriticnogvremena (341,4 min) postiže pri sledecimuslovima: C0=50 mgL-1, ma=12 g and pH4,53, dok metoda RSM smatra pH vrednostfaktorom koji nema znacaja po odziv uispitivanom opsegu, i postiže maksimalnokriticno vreme od 314,8 min, pri istim ostalimuslovima kao i ANN.Iskorišceni adsorbent, zasicen jonima bakra,je zatim spaljen i dobijeni pepeo je iskorišcenkao punilo u proizvodnji gume. Proizvedenasu cetiri uzorka gume sa razlicitim sadržajempepela. Pracen je proces vulkanizacijegume, odreena su mehanicka svojstvagotovog proizvoda i izvreno je poreenjedobijenih rezultata izmeu uzoraka sa ibez dodatka pepela. Rezultati su pokazalida dodatak pepela u strukturu gume neutice znacajno na njene mehanicke osobine.Meutim, povecanje sadržaja pepela u gumidovodi do povecanja energije aktivacijeprocesa vulkanizacije, što se može smatratiunapreenjem procesa proizvodnje gume uslucaju proizvoda velikih dimenzija. Nakraju, ispitano je izluživanje bakra iz gotovihproizvoda od gume. Rezultti su pokazali da jekolicina bakra izluženog u vodu veoma niska,reda velicine 0,001%, što se može smatratizanemarljivim.The potential use of sugar beet shreds forcopper ions removal from aqueous solutionin a fixed-bed column was investigated.Experiments were performed usingBox-Behnken experimental design on threelevels and three variables: concentration ofthe inlet solution (50-150 mgL-1), adsorbentdosage (8-12 g) and pH of the inlet solution(4.0-5.0). The obtained breakthrough curveswere fitted with two common empiricalmodels, Bohart-Adams and dose-response.Observing the asymmetric shape of thebreakthrough curves, the new mathematicalmodel was proposed. The new modelproposes the breakthrough curve composedof two parts, sum of which gives theasymmetrical S-shaped curve, accuratelymatching experimental data. Regarding thelowest average SSer (3.610-3) and highestaverage R2 (0.9989), new model exhibitedthe best fit comparing to the commonly usedmodels. RSM and ANN modelling wereemployed for process variables evaluation andoptimization. The most influential parameterexhibiting negative influence on targetresponse (critical time) was concentration ofthe inlet solution, while the adsorbent dosageexhibited positive influence. Optimization procedure revealed that thehighest critical time (341.4 min) was achievedat following conditions: C0=50 mgL-1,ma=12 g and pH 4.53 by ANN, whileRSM considered pH as insignificant factorand obtained 314.8 min as the highestresponse. Discarded adsorbent, saturatedwith copper ions, was then incinerated andthe obtained ash was used as a rubber filler.Four rubber samples containing differentamounts of added ash were produced. Thevulcanization process was monitored andmechanical properties was measured andcompared with the samples with no ashadded. The results revealed that addition ofash has no significant effect on the rubbermechanical properties. However, as theash content increases, the activation energyof the vulcanization process increases too,which can be considered as an improvementin the cases of large-dimensioned rubberproducts production. Finally, the leachingof the copper from rubber products wasinvestigated. Results showed that very smallamount of copper, order of magnitude 0,001%,were leached from the rubber into the water,which can be considered as insignificant.
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Karunanithi, Rajasekar. « Phosphorus recovery from waste streams using adsorbents ». Thesis, 2017. http://hdl.handle.net/1959.13/1347415.
Texte intégralRésumé :
Research Doctorate - Doctor of Philosophy (PhD)Phosphorus (P) is an important macro-nutrient required for the growth and development of all living organisms. Globally, livestock production generates a large quantity of manure and effluents which are rich in plant nutrients especially nitrogen (N) and P. These waste resources are land applied as an organic fertilizer or soil amendments. However, excess application of manure and effluents beyond the carrying capacity of the soil results in leaching of important nutrients into aquatic environments. This can lead to nutrient enrichment thereby causing various ecological problems such as eutrophication of waterways and resulting in algal blooms. One alternate way of minimising the impact of P is to recover from waste source and reuse as a fertilizer. The main objective of this thesis was to investigate the application of various adsorbents for recovering P from various waste streams. Based on the surface characterization, three adsorbents (allophane, iron oxide and biochar) were selected for the subsequent P adsorption studies. In waste streams, speciation of P in various forms is a significant factor necessary to understand its distribution and transformation in terrestrial and aquatic ecosystems. It was observed that most of the P in manures and biosolids were present as inorganic orthophosphate and orthophosphate monoesters. The sorption kinetics studies showed that among the three adsorbents, biochar showed excellent adsorption characteristics for P recovery which fitted well into the adsorption isotherms, and the maximum adsorption capacity recorded for the adsorbents were 43.29, 35.71 and 90.90 mg g-1 for clay, iron oxide and biochar, respectively. The pseudo-second order kinetics model revealed that the concentrations of both adsorbate as well as adsorbent are the controlling factors for rate of adsorption while the intra-particle diffusion model suggested the prevalence of film diffusion and pore diffusion in the adsorption process. Evaluation of the thermodynamic parameters asserted the adsorption process being spontaneous, favourable and mainly through physisorption. The mechanisms of P recovery were investigated with the help of XPS and XANES techniques, and from the results it is confirmed that various functional groups and minerals such as calcium and magnesium present in the biochar were responsible for adsorption and precipitation of P from waste streams.
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Gung, Chin-Hau, et 宮欽浩. « Water Disinfection Using Silver/Copper- Immobilized Adsorbents Prepared from Waste Materials ». Thesis, 2014. http://ndltd.ncl.edu.tw/handle/09519246927773304151.
Texte intégralRésumé :
碩士國立中興大學
化學工程學系所
102
In this study,use agricultural waste (defatted rice bran, water bamboo husk) as the substrate, and then use it to adsorb silver and copper ions to fixed on agricultural waste, and applied to the water disinfection. Then plastic waste (Styrofoam, plastic bottles) for the polymer substrate for Mixed Matrix Membrane, mixing 20-30 wt% of agricultural waste particles with polymer to prepare pore membrane. After the adsorption of silver ion, used in water disinfection process, hoping use membrane can get lower operating pressure drop (more saving) compared with packed bed in water disinfection process. The results of adsorption, the adsorption capacity of defatted rice bran and water bamboo husk particles for silver were 11.7 and 18.5 mg / g. respectively, for adsorption capacity of copper were 9.2 and 32.9 mg / g. The results of SEM , after batch adsorption process , surface of DRB-Ag+ and WBH-Ag+ is covered by silver. The results of TEM, the size of metallic silver in particle are about 10-50 nm. Experimental results show that the batch disinfection, optimal conditions of antibacterial particles is 0.016 g of DRB-Ag+ (containing silver 0.185 mg) and 0.01 g of WBH-Ag+ (containing silver 0.185 mg) in 2 hours can contain E. coli (E. coli) 2.6 x 105 CFU / mL completely kill, sterilization rate of 99%. Current sterilization procedures that result in two PS / DRB-Ag+ (silver 0.19 mg) flow bactericidal test films, the flow rate of 0.5 mL / min under conditions to 40 mL and the concentration of E.coli containing 2x105 CFU / mL bacteria solution flows through the membrane, the bacteria can be completely killed within E.coli.
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FAN, SHU YA, et 范淑雅. « Transforming bio-waste into adsorbents by a microwave–induced pyrolysis method ». Thesis, 2017. http://ndltd.ncl.edu.tw/handle/84033973375723013816.
Texte intégralRésumé :
碩士明志科技大學
環境與安全衛生工程系環境工程碩士班
105
This study utilized the microwave–induced pyrolysis to pyrolyze different bio-waste into bio-adsorbents. Because of the varied characteristics of original bio-waste, the bio-adsorbents showed quite different physical and chemical properties. A series of adsorption experiments were conducted to evaluate the feasibility of the bio-adsorbent applied to contaminant removal and material recovery. The technology of this research has the advantages of low cost, novelty and recycling, etc., and can achieve the purpose of recycling of waste resources. By the analysis of N2-adsorption-desorption, all the produced bio-adsorbents displayed the properties of type Ⅳ isotherm and slit-shaped opening. The pore structure of bio-adsorbent is mostly related to the lignin and cellulose content in the starting waste. The measurements of CO2 adsorption on the bio-adsorbents were carried out by thermogravimetric analyzer (TGA). Among all the produced bio-adsorbents, the bio-adsorbent derived from the waste corn showed the best adsorption performance of 58.65 mg CO2/g bio-adsorbent, which value is competent to the commercial activated carbon published in previous literatures. The results indicated that the methods to produce bio-adsorbents was feasible and could be further explored. In addition, this study also carried out the waste iodide stream recovery by comparing three bio-adsorbents prepared by microwave–induced pyrolysis with a commercially available activated carbon. The results showed that the iodide adsorption yield better performance in acidic condition than alkaline. Furthermore, a coating of silver ion on bio-adsorbents could enhance the iodide recovery. In the experiment, the silver ion impregnated bio-adsorbent derived from waste peanut shells had the best iodide adsorption of 555.98 μmole iodide/g silver-impregnated-bio-adsorbent. The results show that it is feasible to adsorb iodide from water by silver-coated bio-adsorbent. The results may be helpful for the iodide recovery from waste stream in the optoelectronic industry
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KUMAR, ANUJ. « REMOVAL OF FLUORIDE FROM DRINKING WATER USING LOW COST WASTE ADSORBENTS ». Thesis, 2016. http://dspace.dtu.ac.in:8080/jspui/handle/repository/15326.
Texte intégralRésumé :
Fluoride is a poison that accumulates in our bones. It has been associated with cancer in
young males; osteoporosis; reduced I.Q; and hip fractures in the elderly, to name a few.
Fluoride in nature exists as mineral deposits and, naturally, contaminates our ground water
resources. Besides, surface water is also being polluted by fluoride due to various
anthropogenic activities. The permissible limit of fluoride concentration in drinking water
is 1.5mg/L according to WHO guidelines. Therefore, knowledge of its removal, using best
technique with maximum efficiency is needed. Among various techniques adsorption
occupies a prominent place in fluoride removal. As cost is an important consideration in
most developing countries, efforts have been made to explore the possibility of using
various low cost adsorbents that are abundant, readily available and are derived from waste
materials.
In this study, the adsorption behavior of Lemon peel powder and Pineapple peel powder
has been studied in order to consider its application for fluoride removal. The batch
adsorption method was employed: Laboratory investigation of the potential of Lemon peel
powder and Pineapple peel powder to remove fluoride from aqueous solution has been
studied. The effects of various experimental parameters such as pH , adsorbent dosage and
contact time were investigated . The equilibrium data have been analyzed by the Langmuir
and Freundlich models.
17
Tizaoui, Chedly, et M. J. Slater. « The design of an industrial waste-water treatment process using adsorbed ozone on silica gel ». 2003. http://hdl.handle.net/10454/2674.
Texte intégralRésumé :
NoA new technique using ozone loaded on adsorbents for industrial waste-water treatment has been investigated. This is a three-step process: ozone adsorption on a fixed bed column; water treatment on the bed loaded with ozone; and finally drying/ regeneration of the wet bed. Silica gel of mean particle size of 1.5 mm has been tested for ozone loading capacities followed by water treatment, both at ambient temperature. The mechanisms of the mass transfer process during ozone loading and water treatment have been established. The drying of the adsorbent using vacuum and dry air is feasible, but it is a time-consuming operation. A design procedure is described for the whole system.
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Lin, Liang-Yi, et 林亮毅. « Optoelectronic industrial waste derived porous adsorbents and their application for the capture of CO2 greenhouse gas ». Thesis, 2012. http://ndltd.ncl.edu.tw/handle/72723271837988688514.
Texte intégralRésumé :
博士國立交通大學
環境工程系所
100
The carbon dioxide (CO2) capture and storage (CCS) technologies have received out-breaking concerns after the Kyoto Protocol came into force in 2005. Among capturing technologies, adsorption is regarded as one of the feasible approaches which can limit the CO2 emission. Mesoporous silica materials with high surface area, large pore size and large pore volume are considered as good candidates for CO2 capture. However, the requirements of tedious processing time and expensive manufacture costs strongly limited their applications. Furthermore, the global emission quantity of CO2 is so huge that it may consume tremendous amount of resource materials to capture the CO2 greenhouse gas. On the other hand, with the evolution of semiconductor and optoelectronic industries, huge amounts of siliceous waste powder are significantly increased. Such waste powders are light-density with bulky volume and are thus difficult to be transported and disposed. Therefore, additional expenses on waste treatment and landfill disposal are needed. So if the captured sorbent can be obtained from product wastes, the cost-effectiveness of the CO2 capture technology and the waste treatment and disposal problem will be resolved simultaneously. This study intends to reutilize the waste powder as an alternative resource for the production of mesoporous silica materials via either solution precipitation method or aerosol spray approach. The structural properties and cost-effectiveness of the recycled materials on CO2 adsorption performance was investigated as well. The results showed that the waste powder can be directly converted in to mesoporous silica MCM-41(DU)-F with high surface area (788 m2g-1), large pore size (4.5 nm) and large pore volume (1.1 cm3g-1) with the assistance of ionic surfactant of CTAB, hydrofluoric acid as well as ammonium hydroxide. Through similar pathway, silica materials with hierarchically mesocellular structures can be facilely prepared by using single F127 surfactant. The concentrations of hydrofluoric acid and F127 were found to strongly affect the structural properties of the recycled materials. On the other hand, a low-temperature alkali extraction was developed to effectively separate the silicate supernatant and the sediment of sodium fluoride (NaF) from the waste powder. The obtained sediment containing high purity of NaF (>90%), which provides further reuse possibility since NaF is widely applied in chemical industry. The supernatant is a valuable silicate source for synthesizing mesoporous silica material. In other words, the optoelectronic waste powder can be converted into two valuable resources, the supernatant as the silica precursor and the sediment of sodium fluoride. The mesoporous MCM-41 produced from the waste-derived silicate, namely MCM-41(AF), possessed high specific surface areas (1069 m2/g), narrow pore size distributions (3.0 nm) and large pore volumes (0.97 cm3/g), similar with those of the MCM-41(NaSi) fabricated using commercial silica precursors. This clearly suggests that the silicate supernatant from waste powder can be potential silica resource. This study further extends the preparation of mesoporous materials using waste-derived silicate supernatant as precursors. It was demonstrated that mesoporous MSP(AS) and MSS(HNO3) materials can be synthesized by employing inorganic salts as templating media. The cost analysis shows that the synthesized material of MSS(HNO3) is about five percent of the price of SBA-15 and two percent of the MCM-41 made from commercial silica precursors. Furthermore, the correlation between CO2 adsorption capacity and the pore structure properties (pore size, pore volume and specific surface area) is studied. The result of the linear regression indicates that the CO2 adsorption capacity has the strongest correlation with the total pore volume of the mesoporous materials (R2>0.9). The amine-impregnated MSS(HNO3) can achieve 122 mg/g adsorption capacity, which is superior to that of the original MCM-41(115 mg/g) and SBA-15(117) made from commercial precursors under the same conditions. The MSS(HNO3) prepared using optoelectronic industrial waste powder as the silica source via salt-templated aerosol spray approach exhibits several important advantages of simple and rapid synthesis, low manufacturing costs and superior CO2 adsorption performance. Therefore, it could be considered as potential and competitive sorbents for CO2 capture from flue gas.
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Tang, Yu-Chieh, et 唐鈺傑. « Porous adsorbents derived from TFT-LCD CVD waste powders for removal of Malachite Green from water ». Thesis, 2016. http://ndltd.ncl.edu.tw/handle/11338302937219448290.
Texte intégralRésumé :
碩士國立中興大學
環境工程學系所
104
Waste gases emitted from Chemical Vapor Deposition (CVD) processes at TFT-LCD manufacturing typically contain a large amount of siliceous particulates, approximately 140,280 tons a year in Taiwan. These siliceous particulates are collected by particulate collectors at plants and outsourced the disposal by landfill at high costs, which may also lead to environmental pollution. To avoid the disposal of the large quantify of siliceous waste and minimize the environmental impact, the study aims to utilize the siliceous waste and convert it to porous materials as adsorbents to remove contaminants from water. Particularly, considering that the extensive use of Malachite green in aquaculture and its toxicity, the siliceous waste-derived porous adsorbents are used to remove Malachite green from water. To improve the performance of the adsorbents, the adsorbents are modified by physical and chemical means in order to optimize the parameters for preparation of the adsorbents. Removal of Malachite green using the adsorbents are proceeded in batch experiments and effects of temperature, pH, concentration and salt are examined. The results reveal that the siliceous waste powder cannot adsorb Malachite green while the siliceous waste-derived porous adsorbents can successfully remove Malachite green from water. The adsorbents can be also used with 90% regeneration efficiency after the regeneration. In addition, this study also determines the cost for the preparation of the adsorbents from the siliceous waste and evaluates the economic feasibility to utilize the siliceous waste to develop porous materials.
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Jaria, Guilaine Marques. « Production of waste-based adsorbents for the removal of pharmaceuticals from water : chemical activation and modification ». Doctoral thesis, 2020. http://hdl.handle.net/10773/30466.
Texte intégralRésumé :
The sustainable development of society implies the adoption of strategies
related to waste management and valorization (in a circular economy
perspective) and to effluent treatment (namely for the removal of
pharmaceuticals from water). Being adsorption by activated carbon (AC) a
well-established method for water treatment, this work focuses on the
production of AC using residues, namely sludge from pulp and paper industry,
for the removal of pharmaceuticals from water. This approach aims to foster an
integrated solution for the two environmental issues involved in this work.
Primary pulp and paper mill sludge (PS) showed a great potential to produce
carbon-based adsorbents, relatively to biological sludge (BS). Through the use
of PS and a production process involving chemical activation and pyrolysis, it
was possible to produce AC in both powdered and granular (using a binder
agent) forms, with high surface areas (SBET) (similar to those of commercial AC
with the same granulometry). The produced powdered AC presented, in batch
adsorption systems, adsorption capacities for the pharmaceuticals
carbamazepine (CBZ), sulfamethoxazole (SMX) and paroxetine (PAR), in the
same magnitude of commercial AC. However, when applied in wastewater
matrix, variations in the adsorption capacity of the produced AC for the studied
pharmaceutical was observed, namely in the case of SMX, which decreased,
and PAR, that increased.
The produced granular AC showed, in batch adsorption systems, lower
adsorption capacity for the three pharmaceuticals CBZ, SMX, and PAR, than
the commercial granular AC used as reference. Also, in this case, a reduction
in the adsorption capacity for CBZ and SMX was observed for wastewater
matrices. In fixed-bed column studies (continuous mode) the produced
granular AC presented a higher breakthrough volume and adsorption capacity
for CBZ for the lower flow-rate. Also, it was observed a reduction of the
adsorption capacity with the increase of the complexity of the aqueous matrix
(distilled water > wastewater > multicomponente solutions – with the three
pharmaceuticals – in wastewater).
The application of different functionalization methods to the powdered AC
surface showed to be an interesting approach, evidencing an increase in the
selectivity of some functionalized AC for some of the pharmaceuticals under
study, despite the general reduction in their SBET.
Concluding, this work demonstrates the potential of PS from pulp and paper
mill industry to produce alternative AC, particularly in the powdered form, to be
applied in the removal of pharmaceuticals from water.O desenvolvimento sustentável da sociedade implica a adoção de estratégias ligadas à gestão dos resíduos e sua valorização (numa perspetiva de economia circular) e ao tratamento de efluentes (nomeadamente, para a remoção de fármacos da água). Sendo o processo de adsorção por carvão ativado (CA) um método bem estabelecido para o tratamento de águas, este trabalho incide sobre a produção de CA a partir de resíduos, nomeadamente lamas da indústria da pasta e do papel, para a remoção de fármacos da água. Esta abordagem pretende proporcionar uma solução integrada nos dois desafios ambientais anteriormente referidos. Comparativamente com as lamas biológicas (LB), as lamas primárias (LP) da indústria da pasta e do papel, mostraram ter um grande potencial para a produção de adsorventes à base de carvão. A partir de LP, e usando um processo de ativação química e pirólise, foi possível produzir CA, quer na forma de pó, quer na forma granular (usando um agente aglomerante) com elevadas áreas superficiais (SBET) (comparáveis às de CA comerciais da mesma granulometria). Os CA produzidos em pó apresentaram, em sistemas descontínuos de adsorção, capacidades de adsorção para os fármacos carbamazepina (CBZ), sulfametoxazol (SMX) e paroxetina (PAR), da mesma ordem de grandeza que os CA comerciais. Contudo, quando aplicados em matrizes de efluente real, observam-se variações na capacidade de adsorção dos CA produzidos para os fármacos em estudo, principalmente no caso do SMX, que diminuiu, e da PAR, que aumentou. O CA granular produzido apresentou, em sistemas descontínuos de adsorção, menor capacidade de adsorção para os três fármacos CBZ, SMX e PAR, do que o CA granular comercial de referência. Também neste caso, se verificou uma redução da capacidade de adsorção da CBZ e do SMX em matrizes de efluente real. Estudos realizados em colunas de leito-fixo (modo contínuo) mostraram que o CA granular produzido apresentou maior volume de rutura e maior capacidade de adsorção da CBZ para o menor fluxo. Verificou-se, ainda, a redução da capacidade de adsorção com o aumento da complexidade da matriz aquosa (água destilada > efluente real > soluções multicomponente - com os três fármacos - em efluente). A aplicação de diferentes metodologias de modificação ou funcionalização da superfície dos CA em pó mostrou ser uma abordagem interessante, observando-se um aumento de seletividade de alguns CA funcionalizados para alguns dos fármacos em estudo, apesar da redução geral da SBET destes. Em suma, este trabalho demonstra o potencial das LP da indústria papeleira para a produção de CA alternativos aos CA comerciais, em particular para a formulação em pó, e para a sua aplicação na remoção de fármacos das águas.
Programa Doutoral em Química
21
Torrinha, Maria Beatriz de Queiroz e. Lencastre de Fleming. « Adsorption of Gold from Leach Liquors using Tannin Adsorbents - Towards a Benign Au Recovery from E-waste ». Dissertação, 2020. https://hdl.handle.net/10216/126881.
Texte intégral
22
May, Michael Lee. « Preparation and laboratory evaluation of stationary-phase iron-oxide-based adsorbents for removal of metals from waste waters ». Thesis, 1998. http://hdl.handle.net/1957/33649.
Texte intégralRésumé :
Several potential sorbent materials containing iron oxides were prepared and evaluated for potential to remove divalent metals from waste waters. These included a ferrihydrite-coated sand, maghemite incorporated in Dowex[Trademark] ion exchange resin, gothite and two thermally activated ferrihydrites. Attempts to prepare sorbents from steel shot by coating with ferrihydrite or by thermal oxidization resulted in cemented solids rather than pellets. Ferrihydrite activated at 295��C had a surface area of 113-202 m��/g, followed by gothite at 72-92 m��/g and ferrihydrite-coated sand at 0.78-1.4 m��/g. Zinc adsorption was evaluated by placing 5 g ferrihydrite-coated sand, 0.1 g maghemite in Dowex or 0.1 g gothite in batch reactors containing 40-50 mL of zinc solution, adjusting to various pH values, allowing to react for 96 hours, and analyzing the supernatant for zinc. The data fitted poorly to an ion exchange model using nonlinear regression. The adsorption site densities determined from the regression analysis were 8.0x10������ moles per gram of ferrihydrite-coated sand and 4.1x10������ moles per gram of White. Maghemite in Dowex did not provide any additonal zinc removal capacity in excess of the ion exchange capacity of the resin. Kinetic experiments showed that zinc adsorption onto ferrihydrite-coated sand was 86% complete after 96 hours. Based upon this study, the most promising sorbent appears to be gothite, although the "activated ferrihydrites" are also worthy of further study. Neither ferrihydrite-coated sand and maghemite in Dowex appear to be practical sorbents, based on their low zinc adsorption site density. Maghemite in Dowex might be useful in applications requiring magnetic sorbents.Graduation date: 1999
23
Zeng, Wan-Ting, et 曾婉婷. « Utilization of rice husk agriculture waste for the fabrication of porous silica adsorbents and their performance for air pollution control ». Thesis, 2016. http://ndltd.ncl.edu.tw/handle/phjk7s.
Texte intégralRésumé :
博士國立交通大學
環境工程系所
105
As the energy crisis and resource shortage continue, the rice husk becomes an agriculture valuable waste resource which can be made into various kinds of energy products and resource materials. On the other hand, the capture of CO2 and the control of VOCs emitted from industrial sources are two of the most important air pollution issues. This study intends to reutilize the rice husk as the silica source for the synthesis of porous silica materials and to investigate the effects of structural properties of the waste-derived-materials on CO2 and VOCs adsorption performance. In this study, alkali fusion method was employed to extract the silica from rice husk, and the effects of fusion temperature and extraction temperature on the textural properties of waste-derived materials was investigated. Unlike the conventional methods for preparing large-pore silica materials in which toxic and expensive additives were employed as swelling agents, the obtained waste-derived silica materials with large mesopores could be facilely prepared via a simple temperature-controlled approach without adding pore expanders in this study. The correlation between CO2 adsorption capacity and the textural properties (pore volume, pore size and specific surface area) was demonstrated, and a linear correlation between CO2 adsorption capacity and the total pore volume of the adsorbents was clearly observed. This indicated that the total pore volume of the adsorbent plays a dominant role in determining the CO2 adsorption performance. To reduce the energy consumption and processing time for the preparation of porous silica materials as CO2 adsorbents, a rapid and simple method for the preparation of porous silica nanoparticles (PSNs) directly from agricultural waste of rice husk was developed. Compared with the traditional alkaline fusion and surfactant-templated methods for preparing waste-derived porous silica materials, this method possessed important advantages of a cost-effective, and energy-saving process with faster production rate. Results showed that the (NH4)2SiF6 salt formed during the synthetic process was an effective pore structure medium, which can be easily removed and recovered for further reuse by washing with water. Furthermore, compared to MCM-41, SBA-15 and SBA-16, the PSNs showed the best proformance on CO2 adsorption conditions, probably due to its larger pore volume. On the other hand, the influence of pore structural properties of porous silica materials on adsorptive removal of volatile organic compounds (VOCs) was also investigated. In particular, for the first time, micro-/mesoporous RSBA-16 materials were synthesized by rice husk derived sodium silicate as a silica source. The pore structural properties of waste-derived SBA-16 materials were controlled and optimized by adjusting the surfactant/silica molar ratio for achieving the best adsorption performance of acetone, and the relationship between structural properties and acetone adsorption performance of RSBA-16 adsorbents was investigated. The results indicated that specific surface areas in both micro- and meso-pore ranges were the main factor that determined the superiority of acetone adsorption capacity of RSBA-16(0.004) adsorbents (179 mg/g) over other adsorbents such as mesoporous RMCM-41 (108 mg/g) and micro-/mesoporous RSBA-15 (152 mg/g). The results suggested that RSBA-16(0.004) which had high adsorption rate, high adsorption capacity, high cyclic stability and relatively low chemical cost can be considered as a potential adsorbent for VOCs removals.
24
Marques, Vitor da Costa. « Valorization of tangerine peels in the preparation of adsorbents for removal of Ni(II) from aqueous solutions ». Master's thesis, 2018. http://hdl.handle.net/10198/22626.
Texte intégralRésumé :
Mestrado de dupla diplomação com a UTFPR - Universidade Tecnológica Federal do ParanáThe discharge of industrial and domestic wastewater is one of the main causes of contamination of water bodies by heavy metals. Among these heavy metals, nickel (Ni) is one of the most used in industrial processes, such as the production of alloys, stainless steel and automotive batteries, as well as electroplating activities, causing high concentrations in the effluents of these industries. Several techniques, such as chemical precipitation and filtration, have been studied in order to promote the removal of these heavy metals from wastewater. However, these techniques are often financially and technically costly. Under this context, adsorption using activated carbons (ACs) appears as an alternative, which is characterized by being an effective and economically viable technique. Citrus fruits, such as tangerine, are of great importance in the Portuguese economic context. In 2017, just over 374.4 thousand tons were produced, with 10% of this volume corresponding to tangerine. This research aimed, therefore, to produce ACs from tangerine peels and use them in the adsorption of nickel from aqueous medium. The ACs were produced in two stages: activation and carbonization. Upon activation, the hydrothermal carbonization process (HTC) was used considering FeCl3 as activating agent under three concentrations (0.5, 1.0 and 2.5 M). Afterwards, the prepared materials were carbonized in a tubular oven at 800 ºC for 4 h. The samples were named as follows: TW-C (pyrolyzed peels without HTC), TW-Fe-0.5-C / TW-Fe-1.0-C / TW-Fe-2.5-C (HTC and pyrolyzed peels) and TW-Fe-2.5 (peels with HTC without pyrolysis). The physico-chemical properties of the ACs, such as elemental analysis, ash content, acidity and basicity, were determined to correlate with their performance. The kinetic and isotherm adsorption of Ni(II) onto the ACs was assessed at the following operating conditions: 2.5 g L-1 of AC, 25 ºC and pH 6 and modelled by the kinetic models of pseudo-first order, pseudo-second order and Elovich, as well as the adsorption isotherms of Langmuir, Freundlich and the General Isotherm Equation (GIE) of Tóth. The materials TW-C showed the best adsorption results and removed 99% of Ni(II) at pH 9. The kinetic models that best described the adsorption process were pseudo-second order (TW-Fe-2.5-C) and Elovich (TW-C). The GIE of Tóth showed the best fit, however, its parameters did not show statistical significance at the 5% confidence level, being rejected. The Freundlich model was able to represent the experimental data with certain precision (R² reached 0.9557 and 0.9785 for TW-C and TW-Fe-2.5-C, respectively) and statistical significance according to the t-test and F-test.
A descarga de águas residuais industriais e domésticas é uma das principais causas de contaminação de corpos d'água por metais pesados. Entre esses metais pesados, o níquel (Ni) é um dos mais utilizados em processos industriais, como na produção de ligas metálicas, aço inoxidável e baterias de automóveis, bem como na galvanoplastia, originando altas concentrações nos efluentes dessas indústrias. Várias técnicas, como precipitação química e filtração, foram estudadas para promover a remoção desses metais pesados de águas residuais. No entanto, essas técnicas são financeiramente e tecnicamente caras. Como alternativa surge a adsorção utilizando carvão ativado (AC), caracterizada por ser uma técnica eficaz e economicamente viável. Os citrinos, como a tangerina, apresentam relevada importância no contexto económico português. No ano de 2017 foram produzidas pouco mais de 374,4 mil toneladas, onde 10% desse volume correspondeu a tangerina. Tendo este enquadramento em consideração, este trabalho objetivou produzir ACs a partir de cascas de tangerina para aplicação na adsorção de níquel presente em meio aquoso. Os ACs foram produzidos em duas etapas: Ativação e Carbonização. Na ativação foi usado o processo de carbonização hidrotérmica (HTC) considerando FeCl3 como agente ativante em três concentrações (0,5; 1,0 e 2,5 M); posteriormente, os materiais preparados foram carbonizados em forno tubular a 800 ºC por 4 h. As amostras foram nomeadas da seguinte forma: TW-C (cascas pirolisadas sem HTC), TW-Fe-0,5-C / TW-Fe-1,0-C / TW-Fe-2,5-C (HTC e cascas pirolisadas) e TW-Fe-2,5 (cascas com HTC sem pirólise). As propriedades físico-químicas dos ACs foram determinadas por análise elementar, teor de cinzas, acidez e basicidade, para correlacionação com o seu desempenho no processo de adsorção. A cinética de adsorção e isotérmicas de adsorção de Ni(II) nos ACs foi avaliada nas seguintes condições operacionais: 2,5 g L-1 de AC, 25 ºC e pH 6, aplicando os modelos cinéticos de pseudo-primeira ordem, pseudo-segunda ordem e Elovich, bem como as isotérmicas de adsorção de Langmuir, Freundlich e a Equação Geral da Isotérmica (GIE) de Tóth. O carvão TW-C apresentou os melhores resultados de adsorção e removeu 99% de Ni(II) a pH 9. Os modelos cinéticos que melhor descreveram o processo de adsorção foram o de pseudo-segunda ordem (TW-Fe-2.5-C) e Elovich (TW-C). O GIE de Tóth apresentou o melhor ajuste, no entanto, os seus parâmetros não apresentaram significância estatística no nível de confiança de 5%, sendo rejeitado. O modelo de Freundlich foi capaz de representar os dados experimentais com certa precisão (R² atingiu 0,9557 e 0,9785 para TW-C e TW-Fe-2,5-C, respectivamente) e significância estatística de acordo com o teste t e o teste F.
First of all, I would like to thank my parents, Edson and Claudete, without whom I would not be given so many opportunities, I thank you for the support and encouragement during all these years of graduation and for sharing with me the challenges and difficulties faced away from home. I thank my brother for the partnership, complicity, for being present even with the distance. I thank my friends Pedro and Larissa, for their support during this stage and for their friendship over the years. To my supervisor, teacher and friend Tatiane, for all the help, advice and opportunities during the undergraduate years and later with the master's degree. I am grateful to my co-supervisor José, who was fundamental in the execution of this work and for whom I learned to cultivate respect and admiration. I thank my supervisor, Professor Helder, for the opportunity and confidence. My laboratory friends Fernanda, Adriano and Gabriel, who shared their knowledge and helped me with the execution of my practical work. I thank Maria João, technician at the Chemical Process Laboratory, for being helpful and patient. I would like to thank Professor Margarida and the Mountain Research Center (CIMO) for their assistance with my analysis. I am grateful to the Foundation for Science and Technology (FCT, Portugal) for financial support by national funds FCT/MCTES to CIMO (UIDB/00690/2020).
25
Lima, Thalles Perdigão. « Performance and effectiveness of adsorbents prepared from lignocellulosic agro-industrial residues on the abatement of leachate odor containing ammonia ». Master's thesis, 2020. http://hdl.handle.net/10198/23038.
Texte intégralRésumé :
Mestrado de dupla diplomação com o Centro Federal de Educação Tecnológica de Minas Gerais (CEFET-MG)This work aimed to prepare different adsorbent materials (bioadsorbent, pyrochar, hydrochar, and activated carbon), using olive stone and malt bagasse as feedstock and evaluating its performance and effectiveness in the adsorption of ammonia (NH3), deriving from composting leachate. A lab-scale adsorption system was assembled for the adsorption tests. The performance and effectiveness of the adsorbents on NH3 adsorption were evaluated objectively, by chemical analytical measurement, and subjectively by olfactometric assessment using the human sense of smell. The materials' preparation was studied to assess the biomass loss and the carbon released into the liquid phase during the hydrothermal carbonization process. Besides, resultant adsorbents were characterized to study their surface chemistry, elemental analysis, and textural properties. Saturated adsorbents were regenerated using water and subsequently re-used in the adsorption of NH3 coming from the leachate to assess their adsorption capacities after a sorptiondesorption cycle. The hydrochar derived from olive stone, prepared by hydrothermal carbonization assisted by sulfuric acid (H2SO4), was found as the best adsorbent for NH3 removal produced in this work since it has the lowest height of mass transfer zone (0.315 - 0.520 cm) and the highest NH3 adsorption capacity (9.445 - 11.421 mg g-1). The bioadsorbent prepared only by milling and drying olive stones was also capable of adsorbing NH3, showing a height of mass transfer zone of 0.484 - 0.565 cm, and an adsorption capacity of 0.975 - 1.455 mg g-1; besides the advantage of being environmentally-sound since it requires low energy expenditure, and no chemicals are used in its preparation. The olfactometric evaluations confirmed that the adsorbents mentioned above, prepared by olive stone, can reduce odor annoyance of the gases derived from leachate. Finally, the regeneration process using water delivered adsorbents capable of being used in one NH3 sorption-desorption cycle, with satisfactory performance (>70% of the mean NH3 adsorption capacity of its respective first-generation adsorbents), leading to increasing the materials' resource-use efficiency.
Este trabalho teve como objetivo preparar diferentes materiais adsorventes (bioadsorvente, pyrochar, hydrochar e carvão ativado), utilizando caroço de azeitona e bagaço de malte como matéria-prima e avaliar seu desempenho e eficácia na adsorção de amoníaco (NH3), proveniente do lixiviado de compostagem. Um sistema de adsorção em escala de laboratório foi montado para os testes de adsorção. O desempenho e eficácia dos adsorventes na adsorção de NH3 foram avaliados objetivamente, por medição analítica química, e subjetivamente, por avaliação olfatométrica usando o sentido do olfato humano. A preparação dos materiais foi estudada para avaliar a perda de biomassa e o carbono liberado na fase líquida durante o processo de carbonização hidrotermal. Além disso, os adsorventes resultantes foram caracterizados para estudar sua química de superfície, sua análise elementar e suas propriedades texturais. Adsorventes saturados foram regenerados com água e posteriormente reutilizados na adsorção de NH3 proveniente do lixiviado para avaliar sua capacidade de adsorção após um ciclo de sorçãodessorção. O hydrochar derivado de caroço de azeitona, preparado por carbonização hidrotermal assistida por ácido sulfúrico (H2SO4), foi apontado como o melhor adsorvente para remoção de NH3 produzido neste trabalho, por apresentar a menor altura de zona de transferência de massa (0,315 - 0,520 cm) e a maior capacidade de adsorção de NH3 (9,445 - 11,421 mg g-1). O bioadsorvente preparado apenas pela moagem e secagem do caroço da azeitona também foi capaz de adsorver NH3, apresentando uma altura de zona de transferência de massa de 0,484 - 0,565 cm e uma capacidade de adsorção de 0,975 - 1,455 mg g-1; além da vantagem de ser ambientalmente adequado, uma vez que requer baixo gasto de energia e nenhum produto químico é utilizado em sua preparação. As avaliações olfatométricas confirmaram que os adsorventes citados acima, preparados a partir de caroço de azeitona, podem reduzir a incomodidade do odor dos gases derivados do lixiviado. Por fim, o processo de regeneração com água forneceu adsorventes capazes de serem utilizados em um ciclo de sorção-dessorção de NH3, com desempenho satisfatório (> 70% da capacidade média de adsorção de NH3 de seus respectivos adsorventes de primeira geração), levando ao aumento da eficiência de utilização dos materiais.
I am grateful to the Foundation for Science and Technology (FCT Portugal) for financial support by national funds FCT/MCTES to CIMO (UIDB/00690/2020).
26
Verma, Priyanka, et Subrahmanyam Ch. « Bio-waste derived adsorbent materials for waste water treatment ». Thesis, 2014. http://raiith.iith.ac.in/103/1/CY12M1013.pdf.
Texte intégralRésumé :
Corn cobs were used as a source to prepare activated carbon by physical and
chemical activation methods. The physical activation was employed with CO2 and
steam at high temperature of 1,173K while chemical activation with nitric acid and
hydrogen peroxide at ambient temperature. The adsorption studies of a basic dye,
methylene blue, on the activated carbon were investigated. The effects of various
experimental parameters like contact time, adsorbent dosage, MB concentration,
temperature and pH were studied using batch adsorption experiments. The
characterization of the activated carbon was accomplished by using BET-N2
adsorption, Temperature programmed decomposition (TPD) and Thermogravimetric
analysis (TGA). The results obtained from adsorption studies follow Langmuir
adsorption isotherm with maximum monolayer capacity of 94.33 mg/g for CCC,
64.93 mg/g for SCC, 7.02 mg/g for NCC and 4.04 mg/g for PCC. The kinetics of
adsorption was analyzed by different kinetic models like pseudo first order, pseudo
second order, intraparticle diffusion and Evolich. Among these, pseudo second order
was found to be the most appropriate to study the adsorption of MB on physically
activated carbon. The process was found to be endothermic with enthalpy change,
ΔH (kJ mol-1) of 43.27 (CCC), 38.45 (SCC), 151.63 (NCC) & 72.29 (PCC) and
entropy change, ΔS (kJ mol-1) of 1.57 (CCC), 1.33 (SCC), 5.09 (NCC) and 2.41
(PCC) for a temperature change of 300-330 K. The negative value of ΔG (kJ mol-1),
of -29.92 (CCC), -11.14 (SCC), -7.09 (NCC) and -2.14 (PCC), suggests the
spontaneous adsorption of MB on activated carbon.
27
LIN, TING-YANG, et 林庭揚. « Study on the Adsorption of Laboratory Wastes from Aqueous Solution by Eggshell Waste as a Low-Cost Adsorbent ». Thesis, 2019. http://ndltd.ncl.edu.tw/handle/p95nq5.
Texte intégralRésumé :
碩士明志科技大學
化學工程系生化工程碩士班
107
Effective removal of heavy metals and soluble microbial products and dye waste from wastewater is important to ensure environmental and human health. This study attempted to use eggshells as an adsorbent for the removal of heavy metals and soluble microbial products and dye wastes. Eggshell waste (300-500 m) was firstly used to remove heavy metal ions (e.g., Cu2+, Zn2+) as the metal-immobilized carrier, and then the metal immobilized eggshell complex carrier (namely ES-M) to remove soluble microbial products (e.g., proteins) from aqueous solutions. In this study, chicken egg white (CEW) protein was selected as a simulated contaminant for the soluble microbial products. The CEW protein removed by using ES-M as a carrier. Finally, the ES-M-CEW carrier was employed to remove the dye wastes from the aqueous solution. The operating conditions for the removal of CEW protein by immobilized metal eggshells included: rotational speed, pH, isothermal adsorption, time and CEW concentration. The experimental results showed that the optimal rotational speed was at 100 rpm, and at pH 7 CEW solution. Thermodynamic experiments were carried out with different concentrations of CEW, the maximum adsorption protein of immobilized Cu and Zn eggshell was 190.54 mg/g and 163.19 mg/g, respectively. In the kinetic adsorption experiments, the immobilized Cu and Zn eggshell reached equilibrium at approximately 15 and 5 hours, respectively. Additionally, in the Acid Orange dye (AO7) dye removal experiments, the ES-M-CEW carrier with optimal removing AO7 dye was at pH 2, and the maximum AO7 adsorption of ES-Cu-CEW and ES-Zn-CEW was 88.91 and 62.02 mg/g, respectively. For the kinetic experiments, ES-Cu-CEW and ES-Zn-CEW for AO7 removal was equilibrated at 30 and 120 minutes, respectively. Under various pH conditions, the optimal removal of TBO dye was found to be at pH12, the maximum adsorption capacity of ES-Cu-CEW and ES-Zn-CEW was 131.56 and 127.3 mg/g, respectively. In the kinetic experiments, both ES-M-CEW for the removal of TBO dye reached equilibrium within 10 minutes. The experimental results showed that under low cost and simple preparation of the carrier, the eggshell particles are sequentially used as heavy metals, soluble microbial product proteins and dye removal carriers, which is quite feasible in environmental wastewater treatment. Keywords：Powdered eggshell; Chicken egg white; Metal ion; Adsorption isotherms; Dye; Adsorption kinetics.
28
Lin, Yen-Yu, et 林彥宇. « Synthesis of Hydroxyapatite from Calcium Rich Waste as Adsorbent ». Thesis, 2019. http://ndltd.ncl.edu.tw/handle/zvw5tx.
Texte intégralRésumé :
碩士國立宜蘭大學
環境工程學系碩士班
107
The problem of the large amounts of waste products deriving from stone industrial affects not only the environmental impact but also the resources maintenance and the problem of waste management. This study presents the essential features of an environmentally attractive reuse of what is currently considered limestone sludge and marble sludge. A research is currently carried out in order to join this by-product with possible industrial. Accordingly, the aim of this study is to convert limestone sludge and marble sludge into nanocrystalline HA and to achieve control over the size and morphology of the HA crystals by hydrothermal technique, and utilize as an adsorbent for the removal of Pb and Cu from aqueous media. X-ray diffraction analysis confirmed that all powders were composed of a hydroxyapatite phase. The powders were of crystallinity (Xc =98.48-99.54%) The surface morphologies of the hydroxyapatite were examined via SEM and TEM analysis. That consist of aggregates of rod-shaped nanoparticles with a narrow size distribution. That the actual size of the precipitated crystals were 114-201 nm in length. The hydroxyapatite was classified as a typical IUPAC type-IV isotherm with an H3 hysteresis loop, indicating a mesoporous structure based on capillary condensation of N2 in mesopores, which was also confirmed by the measured average pore diameter of 10.25-20.45 nm. The BET surface area and total pore volume of the HAP were estimated to be 74.69-115.04 m2/g and 0.5339 cm3/g. Langmuir isotherm model (R2=0.98-0.99) seems to be the most accurate model and provides a better description for the equilibrium data compared to the other models. According to the Langmuir fitting, the theoretical maximum adsorption capacity was found to be 245.45 mg/g, and more than 99% of Artificial wastewater can be removed by the Hydroxyapatite. Thermodynamic analysis indicated that the process is thermodynamically spontaneous and endothermic process. Kinetic studies revealed that the adsorption process follows the pseudo-second-order model and that the overall adsorption rate is controlled by film diffusion as the dominant mechanism.
29
Lin, Ya-Wen, et 林雅雯. « Preparation of Suspension Adsorbent for Heavy Metals from Waste Oyster Shells ». Thesis, 2007. http://ndltd.ncl.edu.tw/handle/38715848290661727151.
Texte intégralRésumé :
碩士國立屏東科技大學
環境工程與科學系所
95
A suspension adsorbent absorbent made from oyster shells powder was developed for the absorption of heavy metals in rivers. Wasted oyster shells were collected from the roadside at Chia-I County, and these shells were crushed and sieved into five fractions. Chemical and physical properties of the five sieving fractions are analyzed by sedimentional test, XRF, BET analyzer at first. Experimental results indicate that the fraction with 37μm has the highest surface area (6.93m2/g) and CaCO3 content.(90%) There heavy metals, Pb, Cd and Cr; were used for the absorption test of the prepared oyster shells. Results show that 96% of Cd can be removed within 2 h by 74μm and 37μm fractions. And Ca 100% of Cr can be removed after 16h. The percentages of suspension ability are 0.42% for 149um sieving fraction, 0.27% for 104 μm sieving fraction, and 0.30% for 37μm sieving fraction.
30
Huang, Chin-Ming, et 黃欽銘. « Adsorption and Regeneration of Carbon Dioxide from Waste Gas by CaO Chemical Adsorbent ». Thesis, 2007. http://ndltd.ncl.edu.tw/handle/4mx38e.
Texte intégralRésumé :
碩士國立交通大學
工學院碩士在職專班永續環境科技組
95
The purpose of this study is to understand the CO2 adsorption characteristics and its regeneration by limestone from three different mining areas in Taiwan. The important operating parameters being researched are limestone type, limestone supplement volume, number of regeneration times, different CO2 concentration, and gas moisture content. The test result indicates that after calcination the difference between each limestone is very small in terms of their CO2 adsorbing amounts. As the adsorption and regeneration of CO2 was at constant temperature of 700℃, it has greater CO2 absorbing amount and regenerative ability, but its adsorption rate is lower. On the other hand, as regenerated at 950℃ and adsorbed at 650℃, the adsorption rate is faster whereas the adsorption amount is lower. In the experiment of limestone supplement volume, as the CO2 supplement rate increases the adsorption capacity is enhanced. The presence of moisture increases the adsorption capacity of CO2. Increasing the CO2 inlet concentration from 10% to 50% (v/v) leads to an increase of the CO2 adsorption rate, but the adsorption capacity is slightly smaller. Result on the 10 times of cyclic adsorption test shows that the CO2 adsorption capacity reduces gradually, but it still maintains at adsorptive capacity of around 0.2g CO2/gCaO.
31
Liu, Szu-Chen, et 劉思成. « Adsorbent from agricultural wastes for removal of volatile organic compounds (toluene) ». Thesis, 2012. http://ndltd.ncl.edu.tw/handle/x66b65.
Texte intégralRésumé :
碩士國立臺北科技大學
環境工程與管理研究所
100
The concentration of VOCs and the amount of industrial emissions are rising in the atmosphere, and that would be greatly impacting the environment and human health. Therefore, the pollution of VOCs has been concerned around the world. Many countries have strict regulations on VOCs emission standards and are actively seeking reduction technology. Activated carbon adsorption process no only effectively removes the low concentrations of VOCs, but also has capability to recover organic solvent vapor with a high concentration. In order to reduce the use of organic solvents, many studies have pointed out that adsorbing VOCs using activated carbon recovered from agricultural waste material would be a feasible technology. This research aims to use different agricultural wastes (such as waste barley meal, Leucaena leucocephala and bamboo scrap) derived activated carbon with high surface area as the carbon adsorbents. The physical properties included BET and micropore surface area/pore volume and pore size distribution were first investigated. The activated carbon adsorption experiments using toluene vapor as adsorbate was performed to understand the relationships between physico-chemical properties and adsorption capacity. The results revealed that when the temperatures were within a range from 25 to 90℃ and with a concentration between 2,500 and 20,000 ppm, the range of the toluene adsorption capacities for waste barley meal activated carbon, Leucaena leucocephala activated carbon, and spherical bamboo activated carbon were 285–665 mg g-1, 253–916 mg g-1, and 135–183 mg g-1, respectively. The spherical bamboo activated carbon had the smallest adsorption capacity, mainly due to its small surface area of about 446 m2 g-1, which limited its equilibrium toluene adsorption. The toluene adsorption capacity increased with an increase in toluene concentration and a decrease in temperature. The adsorption isotherm was successfully fitted with Langmuir, Freundlich, and Temkin models for all tested sampled and corresponding parameters were determined. Langmuir models showed best fit to the experimental results (R2＞0.999).
32
Lin, Ming-Hui, et 林明輝. « Probability Study of Utilising Wasted Actived Sludge to Produce the Adsorbent ». Thesis, 1996. http://ndltd.ncl.edu.tw/handle/24424075658202372774.
Texte intégral
33
Sabde, ShrirangVishwanth. « Management of Industrial Solid Waste by Utilizing as an Adsorbent for Methylene Blue Removal ». Thesis, 2013. http://ethesis.nitrkl.ac.in/5284/1/211CH1038.pdf.
Texte intégralRésumé :
An adsorbent has been prepared from spent pot liner, an aluminum industry solid waste. Surface activation of SPL is performed using leaching process. Leaching process employed variation factors like L/S ratio, acid-alkaliconcentration. Optimized leaching process is used for further adsorption study. Investigation has been made to explore the possibility of this adsorbent for liquid phase adsorptive removal of methylene blue (MB). Comparative study of raw and activated adsorbent has been performed to investigate effect of activation process. Optimization and designing of experiment is performed using response surface methodology. Initial dye concentration, adsorbentdose, contacttime, pH, temperature were found as significant factor for adsorption of MB dye. Optimization of raw and acidic-alkali treated SPL shows that treated SPL is effective and economical feasible compared to raw SPL.Adsorption isotherms study Experiment yields excellent fits for raw SPL adsorption asRedlich-Peterson>Freundlich>Langmuir>Temkin. Similarly, this order changed for acid-alkali treated SPL as Temkin>Redlich-Peterson >Freundlich>Langmuir.
34
Li, Fang-Yu, et 李方裕. « Synthesis of calcium oxide from waste materials and its modification for a carbon dioxide adsorbent ». Thesis, 2019. http://ndltd.ncl.edu.tw/handle/8u6883.
Texte intégralRésumé :
碩士國立中山大學
化學系研究所
107
The impact of CO2 on climate change is becoming more serious, so CO2 reduction, storage and reuse are very important. Industrial CO2 production processes are usually in high temperature conditions, and CaO has excellent adsorption of CO2 in high temperature environments. Therefore, it is one of the trends to use CaO as a CO2 adsorbent. However, deterioration occurs after performing multiple cycles of adsorption under high temperature conditions, which is one of the disadvantages of CaO. In this study, the common waste eggshell was used as the raw material, and its main component was CaCO3, which was prepared into CaO after chemical treatment. The experiment was divided into two parts. The first part was to modify the surface of CaO with different surfactants and amino-containing polymer. The second part was modified by adding anti-sintered metal oxide. The materials use common waste materials: aluminum cans, scrap iron. Then, the characteristics were analyzed by FT-IR, XRD, SEM, BET, etc., and TGA was used to investigate the amount of CO2 adsorption. According to the results of the first part of the study, it was found that the CaO modified by the amino group-containing polymer had a significant increase in the amount of cyclic adsorption, and the effect of dopamine modification was the best; and from the second part, the addition of aluminum was used for modification. The CaO with the Al:Ca=1:5 has the best cyclic adsorption effect. This experiment uses wastes commonly found in daily life: eggshells, aluminum cans, scrap iron, etc. to synthesize and modify CaO to solve the problem of CO2 emissions, and the way to recycle and reuse waste. It also fully demonstrates the practice of green chemistry.
35
Chen, Yen-jung, et 陳彥融. « Low-Cost Adsorbent (waste tea leaf powder) for the Removal of ADMI from Dye-laden Wastewater ». Thesis, 2009. http://ndltd.ncl.edu.tw/handle/98755798589588620936.
Texte intégralRésumé :
碩士義守大學
土木與生態工程學系碩士班
97
The main purpose of this study is to remove ADMI from dye-landen wastewater using spent tea leaf powder. The results reveal that the removal efficiency of ADMI increases with decreasing pH and increasing temperature. The green tea leaf powder when treated by pressure cooker, exhibited a better removed efficiency than that of black tea leaf powder. The ADMI removal efficiency up to 87% of ADMI 883 could be removed by 2.4 g/L SGTP at pH 3 and final ADMI reduce from 260 to 108. Both Pseudo-second-order and Modified Freundlich Equation models could be used to describe the kinetic adsorption date. The Intraparticle diffusion equation model was used to describe the adsorption of kinetic gradation and shown that the adsorption was controled by a pore diffusion process. The thermodynamic parameters show that the adsorption process is spontaneous and endothermic in nature. Based on the organics of FTIR, it is suggested that the low removed efficency of BTP is due to the lack of O-H functional group on catechins during the fermentation of tea manufacturing process. It is conclude that GTP can be used as an economical viable adsorbent for the removal of colour fore.
36
Huang, Ping-Jen, et 黃秉仁. « Adsorption of Binary Dye Solutions onto the Adsorbent Prepared from Waste Sludge by the Chemical Activation Technique ». Thesis, 2009. http://ndltd.ncl.edu.tw/handle/62675123241126869298.
Texte intégralRésumé :
碩士大葉大學
環境工程學系碩士班
97
The objectives of the research are to prepare the adsorbents using waste sludge as the raw material, and using different chemical activation techniques. The adsorption behavior on the removal of single and binary dyestuff solutions was studied and compare with the results of commercial GAC. Four single (AR4, AR27, MG, and RB5) and two binary dyestuff solutions (MG+AR27 and RB5+AR4) were investigated. Among three chemical activation techniques, the adsorbents using ZnCl2+H2SO4 was found to exhibit the greatest adsorption capability. The results showed that the adsorption of binary dye solutions could be well described by the rate equation of pseudo-second-order reaction. As for the adsorption isotherms, the Langmuir adsorption isotherm could successfully describe most conditions. Based on the data from the adsorption of single dye solution, the p-factor analysis was also applied to predict the adsorption capacity of binary dye solutions.
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ying, Tsai Tsung, et 蔡宗穎. « Study on Waste Fish Scale to Replace Activated Carbon as a Potential Adsorbent for Removal of Color from Textile Wastewater ». Thesis, 2009. http://ndltd.ncl.edu.tw/handle/33338683185818747455.
Texte intégralRésumé :
碩士大葉大學
生物產業科技學系碩士在職專班
97
Tilapia is one of the commercially important fish species in Taiwan. Approximately 90 thousand of tons Tilapia fish scale were processed annually. This has prompted a growing research interest in the production of fish scales adsorbents from a range of residues mainly industrial or fishery by products. Tilapia fish scale was studied as a potential adsorbent for the adsorption of Reactive Red 198（R-R 198）from aqueous solution. In addition, Tilapia fish scale studies were conducted to explore zeta potential, the different dyes to removal color and adsorbance spectra of dyes solution. The effects of pH , temperature and adsorbent dosage on decolorization by fish scale were studied. Kinetic studies was also carries out to study the effectiveness of dye removal. Greater dye-removal percentage was obtained with a decrease in the initial concentration of dyes and an increase in amount of adsorbent used. Equilibrium isotherms were analysed by Freundlich, Dubnin-Radushkevich, Langmuir, Redlich-peterson and Temkin isotherm equations using correlation coefficients and five different error functions. The experimental data are fitted to the Langmuir isotherm equations.
38
Genu, Aurelia Khanyiswa. « Radionuclide liquid waste treatment of 68[superscript]Ge by graphene oxide based nanomaterials ». Diss., 2019. http://hdl.handle.net/10500/25715.
Texte intégralRésumé :
Radionuclide liquid wastes generated from nuclear facilities can affect humans and the environment, thus substantial attention for their safe management has been received worldwide. Treatment of radionuclide liquid wastes is an important step in its management. In the present work, new composite nanomaterials, graphene oxide base nanomaterial (GO) are developed for treatment purpose.
Graphene oxide (GO), one of the most graphene derivatives, its unique properties, such as chemical stability, hydrophilicity, large surface area and functional groups, make them able to form strong chemical bonds with radionuclides. GO was successfully synthesized via Hummers method, characterized by Raman spectroscopy, X-Ray Diffraction (XRD), UV/Vis Spectroscopy, Fourier transform infrared spectroscopy (FTIR) and Scanning electron microscopy (SEM) and applied as an adsorbent in removal of the metallic long-lived radionuclide 68Ge from of aqueous solution
The method used for evaluation of nanomaterials retention properties was sorption experiment, being based on contact of solid material with tracer solution under defined boundary conditions (solid/solution ratio, solution composition etc.). Two sorption experimental methods were used in this study. Firstly, an aqueous solution of 68Ge radionuclide solution mixed with GO solution, the solution was filtered using syringe filter membrane unit and the aliquot was quantified by gamma spectrometry. Secondly, the 68Ge radionuclide was mixed with GO solid powder, suspension rotated in a mechanical shaker, centrifuged, an aliquot of 1.0 ml sample taken for gamma spectroscopy and the supernatant was put in an oven to dry overnight for characterization analysis. The results obtained from experiments were the evaluated, using sorption percentage equation and showed that the GO had much low sorption capacity for the pre-concentration of radionuclides from aqueous solutions. The function of the pH, the ionic strength and the reduction of GO will be investigated for future studies for the improvement of the research results.Physics
M. Sc. (Physics)