Tesis sobre el tema "Nickel Vanadium"
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Davila, Armas Carlos Enrique. "The extraction of vanadium and nickel from petroleum cokes". Thesis, Imperial College London, 1988. http://hdl.handle.net/10044/1/47018.
Texto completoChassagneux, Evelyne. "Corrosion du nickel en présence de pentoxyde de vanadium". Grenoble 2 : ANRT, 1986. http://catalogue.bnf.fr/ark:/12148/cb375966276.
Texto completoLin, Liming. "Craquages d'alcanes sur catalyseurs zeolithiques : influence du nickel et du vanadium". Poitiers, 1987. http://www.theses.fr/1987POIT2316.
Texto completoLin, Liming. "Craquage d'alcanes sur catalyseurs zéolithiques influence du nickel et du vanadium /". Grenoble 2 : ANRT, 1987. http://catalogue.bnf.fr/ark:/12148/cb37607521d.
Texto completoHizem, Neila. "Etude des propriétés électro-optiques des impuretés vanadium et nickel dans GaAs". Lyon, INSA, 1989. http://www.theses.fr/1989ISAL0028.
Texto completoCADET, VALERIE. "Etude de l'empoisonnement des catalyseurs de fcc par le nickel et le vanadium". Paris 6, 1989. http://www.theses.fr/1989PA066565.
Texto completoLovis, Florian [Verfasser]. "Self-organization of composite model catalysts : vanadium and nickel oxides on Rh(111) / Florian Lovis". Hannover : Technische Informationsbibliothek und Universitätsbibliothek Hannover, 2011. http://d-nb.info/1011398354/34.
Texto completoBarrachin, Marc. "Contribution a l'etude de l'ordre local dans le systeme nickel-vanadium par diffusion diffuse de neutrons". Paris 11, 1993. http://www.theses.fr/1993PA112346.
Texto completoGascon, German. "Contribution à l'étude de la séparation/extraction et à l'identification des composés du nickel et du vanadium dans un brut pétrolier". Thesis, Pau, 2018. http://www.theses.fr/2018PAUU3035.
Texto completoThis PhD work were mainly dedicated to the fractionation of crude oil and petroleum products in order to better caracterize metals compounds (mainly V and Ni) in these complex matrices. It was determined that V and Ni compounds present in the crude oils and residues are concentrated mainly in their more polar fractions, that is to say, resins and asphaltenes. Concerning sulfur compounds, it was found that they are concentrate in the resins and aromatics fractions. All these results were similar to reported in the literature.It was also found the content of V and Ni compounds that precipitate together with the asphaltenes depends linearly of solubility parameter of solvent used for the precipitation of asphaltenes, so, for solvents with solubility parameters close to 16 MPa0.5, the percentage of asphaltene soluble increases. So it can be concluded the true percentage of asphaltenes present in the crude oil is equal to the percentage of insoluble asphaltenes plus the percentage of soluble asphaltenes. For this type of asphaltenes, it was found that they have a molecular weight distribution very similar to insoluble asphaltenes, and not a lower molecular weight, as originally thought (Speight and Mitchell, 1973).With respect to the distribution of molecular weights for the V compounds present in the samples evaluated, at least three molecular weight distributions were identified. Those were identified as compounds with high molecular weight (HMW), medium molecular weight (MMW) and low molecular weight (LMW) following the nomenclature previously reported in the literature. (Desprez et al., 2014).On these distributions, we has found that compounds of V, Ni and S with HMW predominate in the asphaltenes, which is characteristic of nanoaggregate compounds. With respect to the compounds with MMW, these were observed in a greater proportion in maltenes. It should be noted the presence of compounds with HMW in all maltenes evaluated, which for the reasons discussed above, can be considered an unavoidable evidence of the presence of soluble asphaltenes.With respect to the separation/extraction methods developed, it was possible to separate the different distributions of molecular weights initially identified in maltenes and asphaltenes. In the case of maltenes, for the first time in the literature it was possible to extract the various compounds of V and Ni present in these according to their molecular weight. For the separation in maltenes, liquid-liquid extractions on maltene dissolved in heptane were developed. So, with ACN, it has been possible to extract LMW compounds, while extractions with DMF allowed extracting MMW compounds, staying in the remaining maltene mostly compounds with HMW.For the asphaltene extraction, 11 solvents were evaluated. The study of profile obtained to each extract and remanent, allowed to pose a separation scheme that enabled to get up to 4 different molecular weight distributions. These were obtained with ACN, Acetone and DMF used sequentially. It is important to mention it was found that the insoluble fraction gotten with DMF had the highest molecular weight, even in comparison with the HMW asphaltenes soluble in DMF.With respect to the influence of the concentration on the aggregated compounds, it was found that this does not influence on the presence of compounds with HMW. Nanogregate were found in a solution of asphaltenes diluted 40,000 times (25 mg / L).Regarding the characterization of the extracted fractions, only the fraction corresponding to low molecular weights was studied. Determination of the molecular weight distribution by mass spectrometry and comparison of the GPC ICP MS chromatogram with a porphyrin standards, suggests that these V and Ni compounds present in LMW fraction has a structures quite simple. A deeper characterization will be presented in later work
Se determinó que los compuestos de V y Ni presentes en los crudos y residuos evaluados se concentran principalmente en su fracciones más polares, es decir, resinas y asfaltenos. Con respecto a los compuestos de azufre, se encontró que los mismos se concentran en las resinas y aromáticos. Todos estos resultados fueron similares a lo reportado en la literatura. Igualmente se encontró que el contenido de compuestos de V y Ni que precipitan junto con los asfaltenos depende linealmente del parámetro de solubilidad del solvente usado para la precipitación de los asfaltenos, así para solventes con parámetros de solubilidad cercanos a 16 MPa0.5, el porcentaje de se asfalteno soluble incrementa, por lo que se puede concluir que el porcentaje verdadero de asfaltenos presente en el crudo es igual al porcentaje de asfaltenos insoluble más el porcentaje de asfaltenos solubles. Sobre este tipo de asfaltenos, se encontró que los mismos poseen una distribución de pesos moleculares muy similar a la de los asfaltenos insolubles, y no un peso molecular mucho menor, como se pensaba en un principio. Con respecto a la distribución de pesos moleculares para los compuestos de V presentes en las muestras evaluadas, se identificaron al menos tres grandes distribuciones de pesos moleculares. Las mismas se identificaron como compuestos con alto peso molecular o high molecular weight (HMW en inglés), medio peso molecular o medium molecular weight (MMW en inglés) y bajo peso molecular o low molecular weight (LMW por sus siglas en inglés) siguiendo la nomenclatura reportada previamente en la literatura. Sobre estas distribuciones, encontramos que en los asfaltenos predominan compuestos de V, Ni y S con HMW, el cual es característicos de compuestos agregados. Con respecto a los compuestos con MMW, estos fueron observados en mayor proporción en los maltenos. Es de hacer notar la presencia de compuestos con HMW en todos los maltenos evaluados, la cual por las razones antes expuestas, puede ser considerada una evidencia ineludible de la presencia de asfaltenos solubles. Con respecto a los métodos de separación desarrollados, fue posible la separación de las diferentes distribuciones de pesos moleculares inicialmente identificadas en los maltenos y asfaltenos. En el caso de los maltenos, por primera vez en la literatura fue posible separar los diversos compuestos de V y Ni en función de su peso molecular en HMW, MMW y LMW. La separación si hizo empleando extracciones líquido-líquido a maltenos disueltos en heptano con acetonitrilo para la extracción de compuestos con LMW, seguido de extracciones con dimetilformamida para la extracción de compuestos con MMW, quedando en el malteno remanente de la extracción, mayoritariamente compuestos con HMW. Para los asfaltenos, se evaluaron hasta 11 solventes en la extracción de compuestos de V y Ni. El perfil de los compuestos extraídos, permitió separar hasta 4 distribuciones de pesos moleculares diferentes con ACN, acetona y DMF usados secuencialmente. Con respecto a los compuestos con HMW, se encontró que la fracción insoluble con DMF presenta un mayor peso molecular que los asfaltenos con HMW solubles en estos. Con respecto a la influencia de la concentración en la determinación de compuestos con HMW la caracterización de los compuestos de V y Ni, los mismos fueron determinados aun en una solución de asfaltenos diluida 40.000 veces (25 mg/L). En lo referente a la caracterización de las fracciones separadas, solo fue estudiada inicialmente la fracción correspondiente a bajos pesos moleculares. En la misma, la determinación de la distribución de pesos moleculares por espectrometría de masa y la comparación en el cromatograma por GPC-ICP MS de estándares porfirínicos, sugiere que estos compuestos de V y Ni con LMW son metaloporfirinas simples presentes en el crudo con estructuras bastantes sencillas. Una caracterización más profunda será presentada en trabajo posteriores para esta y las demás fracciones
Ikyereve, Rose E. "Investigations into the pre-treatment methods for the removal of nickel (II) and vanadium (IV) from crude oil". Thesis, Loughborough University, 2014. https://dspace.lboro.ac.uk/2134/16401.
Texto completoDesprez, Alain. "Caractérisation moléculaire et élémentaire des produits pétroliers lourds". Thesis, Pau, 2014. http://www.theses.fr/2014PAUU3052.
Texto completoThe crude oils available for the refining industry are heavier and heavier and more concentrated in metals and heteroelements. It is thus of great importance to study the speciation of these species within the petroleum products and their behavior during the refining processes. To answer that problematic, elemental and molecular characterization techniques have been used, mainly High Resolution ICP MS and FT ICR MS for the elemental and molecular characterization respectively. The analytical techniques quoted are used for the analysis of several petroleum products sometimes originating from refining processes and the information obtained at the elemental and molecular level are combined to improve our understanding of the mechanisms occurring within our samples during refining activities
TORREALBA, MARIANA. "Modification de zéolithes Y et d'un catalyseur de craquage par traitement hydrothermal et par ajouts de nickel ou de vanadium". Poitiers, 1992. http://www.theses.fr/1992POIT2295.
Texto completoUbaid, Kassis Sara. "Magnetization and Transport Study of Disordered Weak Itinerant Ferromagnets". Kent State University / OhioLINK, 2009. http://rave.ohiolink.edu/etdc/view?acc_num=kent1247865424.
Texto completoKeränen, A. (Anni). "Water treatment by quaternized lignocellulose". Doctoral thesis, Oulun yliopisto, 2017. http://urn.fi/urn:isbn:9789526215143.
Texto completoTiivistelmä Edullisia ja kestäviä vedenkäsittelytekniikoita tarvitaan kasvavien vesiongelmien ratkaisemiseen. Lignoselluloosaa, kuten sahanpurua, syntyy suuria määriä teollisuuden sivutuotteena. Sen reaktiivisia funktionaalisia ryhmiä voidaan modifioida kemiallisesti ja valmistaa siten biopohjaisia vedenkäsittelykemikaaleja. Tutkimustietoa oikeiden jätevesien puhdistuksesta biopohjaisilla ioninvaihtomateriaaleilla tarvitaan lisää, jotta materiaalien käyttöä voidaan kehittää ja edistää. Tässä väitöstyössä valmistettiin anioninvaihtomateriaaleja modifioimalla kemiallisesti viittä suomalaista lignoselluloosamateriaalia: männyn sahanpurua ja kuorta (Pinus sylvestris), kuusen kuorta (Picea abies), koivun kuorta (Betula pendula/pubescens) ja turvetta. Menetelmässä käytettiin epikloorihydriiniä, etyleenidiamiinia ja trietyyliamiinia orgaanisessa liuotinfaasissa. Työssä keskityttiin erityisesti nitraatin poistoon sekä synteettisistä että oikeista jätevesistä. Materiaalien soveltuvuutta teollisiin sovelluksiin arvioitiin maksimisorptiokapasiteetin, sorptioisotermien, kinetiikka- ja kolonnikokeiden sekä pH:n, lämpötilan ja muiden anionien vaikutusta tutkivien kokeiden avulla. Kaikki viisi kationisoitua tuotetta poistivat yli 70 % nitraatista laajalla pH-alueella (3–10). Kationisoitu männyn sahanpuru osoittautui parhaaksi materiaaliksi (32,8 mg NO3-N/g), ja se toimi laajalla lämpötila-alueella (5–70°C). Kolonnikokeet osoittivat sen olevan helposti regeneroitavissa ja uudelleenkäytettävissä. Tuotetta testattiin myös kaivos- ja kemiantehtaan jäteveden käsittelyyn, ja kokeissa havaittiin hyviä nikkeli-, uraani-, vanadiini- ja kobolttireduktioita. Männyn sahanpurua modifioitiin vertailun vuoksi myös kationisella monomeerilla, N-(3-kloro-2-hydroksipropyyli)trimetyyliammoniumkloridilla. Tuotteen maksimisorptiokapasiteetiksi saatiin 15,3 mg NO3-N/g ja se poisti nitraattia saastuneesta pohjavedestä. Kokonaisuudessaan väitöskirjatyö tarjoaa uutta tietoa biopohjaisten ioninvaihtomateriaalien valmistamisesta ja niiden soveltuvuudesta oikeiden teollisuusjätevesien käsittelyyn
Delgado, Muñoz Daniel. "Catalytic valorization of natural gas and biomass-derived feedstocks by metal oxides". Doctoral thesis, Universitat Politècnica de València, 2019. http://hdl.handle.net/10251/122298.
Texto completo[CAT] Aquesta tesi doctoral es situa dins del marc de l'actual transició energètica, la qual planteja la substitució progressiva de les primeres matèries d'origen fòssil per fonts renovables, tant per a l'obtenció de productes químics com per a la producció de combustibles. En aquest context de transició gradual a les renovables, i tenint en compte els últims pronòstics, les fonts fòssils (principalment el gas natural) i els derivats de la biomassa, exerciran un paper fonamental durant aquest canvi. S'ha dut a terme un estudi sobre la utilització d'òxids metàl·lics (basats en bronzes de wolframi o en òxid de níquel), com a catalitzadors per a: i) la transformació de derivats de la biomassa: de glicerol a acroleïna/àcid acrílic; i de compostos oxigenats de cadena curta presents en efluents aquosos (procedents de tractaments d'extracció de bio-olis de la piròlisi) a combustibles; i ii) la transformació de components del gas natural, concretament l'obtenció d'etilè a partir d'età, mitjançant la deshidrogenació oxidativa. El treball es presenta des del punt de vista de la química de materials, posant l'accent en les propietats fisicoquímiques dels diferents sistemes catalítics, utilitzant tècniques de caracterització convencionals i in situ, a més de reaccions model, amb l'objectiu d'entendre les funcions catalítiques presents en cadascun dels casos. Tant per a la transformació del glicerol en fase gasosa com per a la valorització de les mescles aquoses de compostos oxigenats de cadena curta, s'han utilitzat catalitzadors basats en bronze de wolframi. S'ha intentat posar de manifest la gran versatilitat de composicions i estructures (amb el conseqüent control de les propietats funcionals) que presenten aquest tipus de materials. En aquest sentit, les propietats àcides i redox dels catalitzadors de W - V - O poden ser modulades, per a una mateixa concentració de vanadi, mitjançant el control de la relació de fases cristal·lines (hexagonal i monoclínica) de l'òxid de wolframi. Aquest efecte s'ha estudiat utilitzant la transformació aeròbica de metanol com a reacció "test", i presenta una gran influència en la deshidratació oxidativa de glicerol a àcid acrílic. Al mateix temps, mitjançant la substitució isomòrfica de wolframi per niobi (en el sistema WO3 - Nb2O5), és possible controlar la relació de centres àcids de tipus Brönsted i Lewis en la superfície dels materials. Per una part, els catalitzadors que presenten una relació Brönsted / Lewis alta s'han mostrat més efectius en la deshidratació de glicerol a acroleïna, mentre que els catalitzadors amb unes altes concentracions de tipus Lewis presenten alts rendiments a productes de condensació de compostos oxigenats de cadena curta. Addicionalment, s'han estudiat les diferències entre catalitzadors (ja siguin òxids mixtos W-V-O o W-Nb-O) preparats mitjançant un mètode hidrotermal o mitjançant un mètode de reflux, així com l'efecte que presenta la utilització d'un suport mesoporós (KIT-6), sobre les seves propietats catalítiques en la reacció de transformació aeròbica en fase gasosa d'etanol i glicerol. Finalment, pel que fa referència a la transformació de components del gas natural, s'han utilitzat materials basats en òxid de níquel (suportat sobre diferents òxids i/o promoguts amb diferents metalls) i catalitzadors per a la deshidrogenació oxidativa d'età. En aquest cas, l'estudi s'ha focalitzat principalment en dilucidar els efectes de promotors i suports en la naturalesa i propietats fisicoquímiques de l'òxid de níquel, els quals impliquen un canvi dràstic en les seves propietats catalítiques. Així doncs, s'ha observat que modificant la reductibilitat i les característiques superficials de l'òxid de níquel és possible transformar un catalitzador molt poc selectiu en la deshidrogenació oxidativa de l'età (com és el cas del NiO, amb una selectivitat a l'etilè del 30%) en un dels cata
[EN] The present doctoral thesis is set within the scope of the current energy transition, which considers the progressive substitution of non-renewable fossil sources by renewable feedstocks for the production of chemicals and fuels. In this context of gradual transition, and according to recent energy outlooks, fossil sources (especially natural gas) and biomass feedstocks will play a key role during the shift. A study on the use of metal oxides (based on tungsten bronzes or nickel oxides) as catalysts for different reactions has been conducted. Particularly, they have been studied as catalytic materials for: i) the transformation of biomass-derived feedstocks: glycerol transformation into acrolein/acrylic acid, and the transformation of short-chain oxygenates present in aqueous effluents (derived from extraction processes of pyrolysis bio-oils) into fuels; and ii) the valorization of natural gas components, i.e. the transformation of ethane into ethylene by oxidative dehydrogenation. The work is presented from a materials chemistry perspective, emphasizing the physicochemical characteristics of the different catalytic systems by using conventional and in situ characterization techniques and model reactions (gas phase methanol and ethanol transformation); with the aim of understanding the specific catalytic functionalities present in each case. For both gas phase glycerol transformation and the valorization of short-chain oxygenates aqueous mixtures, catalyst based on tungsten oxide bronzes have been used. The compositional and structural versatility of this structural types (with the subsequent control of their functional properties) will be highlighted. In this sense, the acid-redox properties of W-V-O catalysts can be modulated by controlling the crystalline phase composition in the materials (i.e. hexagonal and monoclinic polymorphs of tungsten oxide) at a fixed V concentration. This effect has been studied by using the gas-phase aerobic transformation of methanol as a surface test reaction. The concentration of the hexagonal and monoclinic polymorphs in the catalysts has also an important influence in the gas-phase transformation of glycerol into acrylic acid. Also, it is possible to control the Brönsted/Lewis acid nature of the surface by the isomorphic substitution of Nb for W in WO3-Nb2O5 system. On the one hand, catalysts showing a higher proportion of Brönsted acid sites are more effective in the glycerol dehydration to acrolein. On the other hand, materials with a higher concentration of Lewis acid sites display high yields to condensation products in the aqueous phase valorization of short chain oxygenates. Additionally, the differences between W-V-O and W-Nb-O catalysts prepared by both reflux and hydrothermal methods have been studied. Also the effect of adding a mesoporous KIT-6 silica as support on the catalytic performance in the gas phase transformation of ethanol and glycerol will be underlined. Considering the transformation of natural gas components, nickel oxide-based materials were chosen (either supported on different oxides and/or promoted with different metals) to perform the oxidative dehydrogenation (ODH) of ethane. In this case the study has been focused on elucidating the effects of both promoters and supports on the nature and physicochemical features of nickel oxide, which lead to a drastic change in the catalytic behavior of these materials. This way, it has been observed that by the modification of the reducibility and the chemical nature of nickel oxide, it is possible to transform an apparently non-selective catalyst in the ODH of ethane (like NiO, showing a selectivity to ethylene of ca. 30 %) into one of the most selective catalysts reported in the literature (presenting a selectivity to ethylene of ca. 90 %).
También me gustaría agradecerle al Prof. Avelino Corma, investigador principal del proyecto SEV-2012-0267, a través del cual he podido realizar mi tesis doctoral enel Instituto de Tecnología Química (SVP-2014-068669).
Delgado Muñoz, D. (2019). Catalytic valorization of natural gas and biomass-derived feedstocks by metal oxides [Tesis doctoral no publicada]. Universitat Politècnica de València. https://doi.org/10.4995/Thesis/10251/122298
TESIS
CASARI, Daniele. "THE GRAIN REFINEMENT AND THE Ni/V CONTAMINATION IN THE A356 ALUMINIUM CASTING ALLOY: AN EXPERIMENTAL STUDY ON IMPACT AND TENSILE PROPERTIES". Doctoral thesis, Università degli studi di Ferrara, 2014. http://hdl.handle.net/11392/2389412.
Texto completoGlénat, Philippe. "Démétallisation biologique de résidus pétroliers lourds". Lyon 1, 1990. http://www.theses.fr/1990LYO10052.
Texto completoGutiérrez, Sama Sara. "Identifications moléculaires des espèces hétéroatomiques et métalliques en lien avec les procédés d’hydrodemetallation et d’hydroconversion". Thesis, Pau, 2017. http://www.theses.fr/2017PAUU3042.
Texto completoThe presence of heteroatoms and metals in heavy fractions of crude oil can cause the deactivation of hydrotreatment and hydrocracking catalysts. Compounds containing these elements are known to be included in macromolecular asphaltene aggregates, which are considered the most problematic components of heavy oil. This thesis aimed for a better understanding of the chemical environment of these species and on the aggregation phenomenon to optimize refining processes. Separation techniques such as Gel Permeation Chromatography (GPC), Advanced Polymer Chromatography (APC) and High Performance Thin Layer Chromatography (HPTLC) were combined with elementary analysis techniques such as Inductively Coupled Plasma Mass Spectrometry (ICP MS) or high-resolution molecular mass spectrometry for the characterization of heavy fractions of crude oil. Here, the size profiles of species that contain vanadium, nickel and sulfur, the most abundant heteroatoms and metals present in petroleum products, were determined by GPC online with elemental detection by ICP MS. The parameters having the most significant impact on size distribution and the evolution over time of aggregates from solutions of different petroleum cuts were optimized. This allowed the comparison between various feeds and effluents and other series of samples and mixtures from pilot units of refining processes by GPC ICP MS. Results obtained could be related to macroscopic characteristics such as viscosity. Hyphenation of the new APC System to ICP MS has been successfully completed. It allowed the mapping of petroleum samples faster than GPC, therefore with less solvent consumption. However, the differences of the APC chromatograms obtained with respect to the GPC profiles suggested significant unwanted interactions of the highly polar compounds of the petroleum samples with the stationary phase, which have been thoroughly studied. Finally, another type of separation was evaluated. HPTLC, of single-use plates, can be applied to the analysis of heavy petroleum products by polarity without prior deasphalting steps while chromatography columns can be deteriorated because of the irreversible adsorption and asphaltene precipitation. To this end, various types of plates and eluents were tested to develop straightforward SAR (Saturates, Aromatics and Resins) separations of Vacuum Gas Oil (VGO) samples. This method, based on single-step migrations with reduced irreversible adsorption and UV monitoring, could be implemented for routine analysis in control laboratories. Very promising results were obtained by the use of cellulose plates for the separation of different families within asphaltene aggregates. Tests on Desorption ElectroSpray Ionization (DESI) MS, Direct Analysis in Real Time (DART) MS and Laser Ablation (LA) ICP MS analyses of the plates have been performed
Caumette, Guilhem. "Analyse de spéciation des métaux dans les produits lourds du pétrole par couplage LC-ICP MS (Chromatographie liquide – Spectromètre de masse à plasma induit)". Pau, 2009. http://www.theses.fr/2009PAUU3029.
Texto completoThe use of heavy petroleum, increasingly popular because of the shortage of energy supplies, is hampered by the presence of heavy metals, such as nickel and vanadium, which negatively affect refining processes. The objective of the thesis was to develop novel analytical methods able to study the metal distribution in petroleum, its fractions and related products. The principal developments include: (i) a high-throughput sensitive method for the analysis of organic matrices based on flow-injection total consumption micronebulisation ICP MS; (ii) a coupling of gel-permeation LC with ICP MS; and (iii) a coupling of normal phase LC – ICP MS allowing the 2D gel-permeation – normal phase characterization of the metal distribution by ICP MS. The methods developed were applied to the analysis of a number of crude oils and their fractions
Djona, Maurice. "Nouveau procédé pour la récupération de Co, Ni, Mo et V à partir des catalyseurs usés". Vandoeuvre-les-Nancy, INPL, 1994. http://www.theses.fr/1994INPL001N.
Texto completoChassagneux, Evelyne. "Corrosion du nickel en présence de V2O5". Phd thesis, Grenoble INPG, 1986. http://tel.archives-ouvertes.fr/tel-00845629.
Texto completoSant, ana Carla Simone. "Especiação de compostos de enxofre, níquel e vanádio em cimento asfáltico de petróleo (CAP) e sua relação com os processos de envelhecimento". Universidade Federal de Santa Maria, 2015. http://repositorio.ufsm.br/handle/1/4277.
Texto completoA especiação de compostos sulfurados em CAP é de grande importância, uma vez que alguns desses compostos são responsáveis pela oxidação de ligantes asfálticos, modificando suas características químicas e físicas. Este trabalho tem como foco a especiação química de classes majoritárias de compostos sulfurados em amostras de CAP virgem e envelhecidas (métodos RTFOT, RTFOT+PAV e RTFOT+SUNTEST) e suas respectivas frações maltênicas. A especiação das classes sulfuradas foi realizada pelo método adaptado de Payzant empregando reações de oxidação específicas e separações cromatográficas por adsorção em sílica. Os teores de sulfóxidos foram obtidos por FTIR, utilizando-se como padrão de sulfóxidos uma solução de referência de tetrametileno sulfóxido (TMSO) em diclorometano. As classes de compostos estudadas foram: sulfurados aromáticos/saturados, tiofenos, sulfetos alifáticos e sulfóxidos. Para isso, foram analisadas comparativamente 6 amostras de CAP virgem e envelhecidas em relação à distribuição dos compostos sulfurados nas três frações obtidas, onde foram analisados os teores de enxofre total a fim de se observar o comportamento dos compostos nessas frações nos diferentes processos de envelhecimento. Com base nesses resultados, observa-se que no processo de envelhecimento ocorrem mudanças estruturais envolvendo quebras de ligações em anéis tiofênicos e formação de novas classes de compostos sulfurados de maior peso molecular. Os compostos de enxofre na forma de sulfóxidos apresentaram um aumento decorrente dos processos de envelhecimento para os envelhecimentos RTFOT e RTFOT/PAV. Também foram analisados os teores de Níquel e Vanádio nas diferentes amostras, em suas frações maltênicas e asfaltênicas por GFAAS, já que estes metais são envolvidos como coadjuvantes no processo de envelhecimento dos CAPs. A distribuição dos metais de Ni e V nas frações asfaltênicas e maltênicas sofreu uma diminuição nos teores destes metais decorrente das perdas por volatilização na forma de metaloporfirinas. Correlacionando-se as alterações químicas e físicas observadas em CAP, as variações nas propriedades viscoelásticas (G*/sin) podem ser um reflexo das alterações que ocorrem nas frações tiofênicas; além disso, a variação no aumento da penetração pode estar relacionada com a variação do teor de asfaltenos e de compostos de caráter e básico, que também podem ser relacionados com as mudanças viscoelásticas dos CAPs. Com base nos resultados obtidos, esse trabalho buscou responder a 6 perguntas principais e norteadoras da tese apresentada: (1) que transformações ocorrem na especiação de compostos de enxofre com o envelhecimento de CAP em curto prazo, longo prazo e sob ação da radiação UV?; (2) qual a classe majoritária de compostos de enxofre em CAP e como esta se altera com o envelhecimento?; (3) que transformações ocorrem nos metais níquel e vanádio com o envelhecimento de CAP em curto prazo, longo prazo e sob ação da radiação UV?; (4) os processos de envelhecimento forçado de CAP (RTFOT, PAV e SUNTEST) conduzem a transformações químicas diferentes em asfaltenos e maltenos?; (5) quais as correlações existentes entre as transformações químicas e físicas em CAP, a partir da especiação química e da reologia após o envelhecimento?; (6) é possível estabelecer alguma ordem de reatividade química para o CAP com base na especiação química e na reologia após o envelhecimento?
Ferry, Sébastien. "Simulation de l’influence des interactions élastiques sur la coalescence dans le système Ni-Al-V". Rouen, 2007. http://www.theses.fr/2007ROUES041.
Texto completoIn this work, the kinetics of isothermal ageing in intermetallic systems were studied using a computer simulation technique based on Onsager microscope diffusion equations. In particular, our focus is on the coarsening kinetics in Ni-Al, Ni-V and Ni-Al-V alloys. To reproduce the microstructures in Ni-based alloys, the elastic interactions were taken into account in our model. First, the model was applied for Ni-Al alloy. Our results are in good agreement with recent experimental observations and simulations results. Then Ni-V alloy was studied. It was shown that our simulations reproduce the experimentally observed monovariant microstructure in this system. The influence of the lattice misfits on stability of two-variant microstructure was demonstrated. Finally, Ni-Al-V alloy was studied. Simulation results showed that proposed model is able to reproduce the complex microstructure in ternaries alloys
Juwono, Alamsyah Mohammad. "Investigations of ultrafine particles emitted by ships and other transport modes in the port of Brisbane". Thesis, Queensland University of Technology, 2014. https://eprints.qut.edu.au/79190/4/Alamsyah%20Mohammad%20Juwono%20Thesis.pdf.
Texto completoKramer, Karl-Heinz [Verfasser]. "Ausscheidungsverhalten von Nickel-Vanadin-Legierungen / Karl-Heinz Kramer". Karlsruhe : KIT-Bibliothek, 2008. http://d-nb.info/1186272325/34.
Texto completoKováč, Lukáš. "Stanovení těžkých kovů v půdách a sedimentech v oblasti Revúce". Master's thesis, Vysoké učení technické v Brně. Fakulta chemická, 2011. http://www.nusl.cz/ntk/nusl-216743.
Texto completoXiao, Wanyao. "Asymmetric Capacitor Based on Vanadium Dioxide/Graphene/Nickle and Carbon Nanotube Electrode". University of Akron / OhioLINK, 2014. http://rave.ohiolink.edu/etdc/view?acc_num=akron1396870651.
Texto completoPernot, Etienne. "Relations entre synthèse, structure et conductivité dans Bi4V2O11 et ses substitués (Cu, Ni)". Université Joseph Fourier (Grenoble), 1994. http://www.theses.fr/1994GRE10178.
Texto completoToscano, Luis Gustavo Sandrin. "Efeito da diluição da chapa base na soldagem com adição de pó de ferro utilizando fluxo experimental". Universidade de São Paulo, 1997. http://www.teses.usp.br/teses/disponiveis/88/88131/tde-15092016-123234/.
Texto completoThe study of the effect of microalloying elements in the chemical composition, microstructure and mechanical properties of the as-welded metaIs obtained by submerged are welding with iron powder addition in High Strength Low Alloy (HSLA) steel were done. Two weld metaIs were made using, BS - 4360 - 50 and USI - SAC - 50 steels, EM - 12K wire, ESAB 400 iron powder and 10.71P experimental flux. Using welding current of 600 A, arc voltage of 34 V, travel speed of 30 cm/min and iron powder flow of 6,7 Kg/h were obtained as-welded metals by single pass into V - groove, that showed good hardenability and refined microstructure. The higher percentage microstructure in the two weld metals was the acicular ferrite. The mechanical tests done were hardness, tensile strength and impact. The weld metal with niobium and vanadium achieve better values of hardness and yield strength than with copper, chromium and nickel weld metal. However, the hardening by solid solution, induced by the high levels of manganese, decreased the impact strength of the two weld metaIs. The non - metallic inclusions nature was investigated by electronic microscopy and EDAX analysis.
Marcano, Brito Francia. "Evaluation des paramètres structuraux des asphaltènes et de leurs effets sur les propriétés physiques et chimiques des bruts". Thesis, Pau, 2012. http://www.theses.fr/2012PAUU3008/document.
Texto completoThe purpose of this work is to provide information that can help in clarifying the mechanism by which asphaltene precipitation occurs in order to optimize the models that predict the phenomenon. The study is divided into three chapters. In the first one, the constituents of aromatic and saturate fractions of some Venezuelan crude oils were associated with the asphaltenes stability. SARA composition was correlated with asphaltene flocculation onsets and the results showed that saturates, similar to resins, have a significant effect on the flocculation process of the asphaltenes. In the second chapter, the concentration of Ni and V was determined in asphaltenes and their fractions A1 and A2. The samples were analyzed using inductively coupled plasma atomic emission spectrometry and elemental combustion analysis. Results show that A1 presents higher Ni and V concentrations than A2, in both stable and unstable crude oils. These results can be explained by strong interactions, such as covalent bonds between the petroporphyrins and the asphaltene molecules. In the final section, the asphaltenes phase envelopes were obteined for a system consisting of asphaltene in a mixture toluene/heptane/CO2. The temperature ranges 10-150 °C with varying concentrations of CO2 between 10 and 20 wt%. The experimental results confirm that increase of pressure leads to increase of solubility of the asphaltenes in the medium. Also, there are two temperature regimes having opposite trends. First, the solubility of the asphaltenes increases with the temperature, then after a threshold value of 80 °C, the stability is getting worse with the temperature
Lee, Yan Huang y 李彥篁. "Hydrothermal Synthesis and Structure Chemistry of Vanadium and Nickel Arsenates". Thesis, 1995. http://ndltd.ncl.edu.tw/handle/01319831142411146083.
Texto completoNancyLin y 林南西. "Extraction of Nickel, Vanadium and Molybdenum from Spent Hydrodesulfurization Catalyst". Thesis, 2013. http://ndltd.ncl.edu.tw/handle/18522540950592042645.
Texto completo國立成功大學
資源工程學系碩博士班
101
It is estimated that more than 13,000 tons of spent hydrodesulfurization catalysts are annually generated in Taiwan, which contains valuable metals like cobalt, molybdenum, nickel, vanadium, etc. If the spent hydrodesulfurization catalysts are disposed directly, the released metals may cause a secondary pollution of the environment. In this study, the spent hydrodesulfurization catalysts were first processed by a thermal pretreatment, and its effects were determined by TOC and XRD analysis. Results of TOC analysis that preheating in higher temperature and longer time will indicated the oil and tar on the surface of spent hydrodesulfurization catalysts were completely removed. The results of XRD analysis confirmed that preheating the samples at 600℃ for 5h provides enough energy to induce an oxidized roasting reaction in samples which transforms the sulphides into oxide. Next, the extraction of nickel, vanadium and molybdenum from spent HDS catalysts by using the sulphtization roasting-leaching process and direct acid leaching process was discussed. The result indicated that the best conditions for nickel, vanadium and molybdenum extraction were: thermal pretreatment at 600℃ for 2h, spent HDS catalyst/ NaHSO4•H-2O(s) mixed mass ratio of 1/7.5, acid roasting temperature of 600℃, acid roasting time of 1h, leaching solution of 3N H2SO4(aq), leaching temperature of 70℃ and leaching time of 30min. The final extraction rate for vanadium, nickel and molybdenum were 100%, 91.2% and 90.6% respectively. Finally, extraction of vanadium, nickel and molybdenum using direct acid leaching method consume much more sulfuric acid than using the sulphtization roasting-leaching method.
JHENG, BAI-JHONG y 鄭百仲. "Effect of elecrtochromic properties on the vanadium pentoxide deoped with nickel by sputter deposition". Thesis, 2016. http://ndltd.ncl.edu.tw/handle/cj6kv5.
Texto completo崑山科技大學
電機工程研究所
104
In this study, RF sputtering deposition of vanadium pentoxide films on ITO glass substrate, as well as RF magnetron co-sputtering deposition of nickel-doped vanadium pentoxide on the ITO glass substrate film were investigated. The films were obtained by changing process time, argon and oxygen pressure ratio and different annealing temperatures. Then in order to investigate the optical properties between the therefore,the film of vanadium pentoxide and nickel doped vanadium pentoxide doped, compositional analysis and electrochromic properties were be determined by cyclic voltammetry, X-ray diffraction, FE-SEM, UV-visible spectrometer, atomic force microspoic and auger electron spectroscopy. Experimental results indicated that the electrochromic properties show significantly higher than other low-time films manufacturing process at non-oxygen,3hrs process time and film thickness of 288.2nm. The transmittance change between colored and bleached states at a wavelength of 600nm was 25.6% because of a larger circulation area as well as a larger capacity. When the argon and oxygen pressure ratio was 15: 1,the vanadium pentoxide films obtained the best electrochromic properties. The transmittance change between colored and bleached states at a wavelength of 600nm was 43.8%. The films show a significant Redox peaks under cyclic voltammetry analysis. The peaks improves the transmittance difference at colored and bleached states. After the vanadium pentoxide thin films processed through different temperature annealing,the flim is crystallized at 400℃ annealing,however,the film annealed at 300℃ has better electrochromic performance than no annealed. The transmittance change between colored and bleached states at a wavelength of 600nm was 28.7% and the films appear a reduction peak under cyclic voltammetry analysis. Nickel-doped vanadium pentoxide film was deposited at fixed time of 2hr by sputtering. When the doping power is 30W, nature properties of the thin film has a little bit of change. Then when the doping power is above 50W, because nickel content in thin film is more. The effect was deepen the vanadium pentoxide thin film in the anode color. The result indicates that the films change its color form anode coloration turn to cathodic coloration observed from the change of a whole circulation volt-ampere graph. When the doping power was 80W , the best electrochromic properties obtained. The transmittance change between colored and bleached states at a wavelength of 600nm was 35.2%. When the nickel-doped power is 10W, the best film electrochromic properties was gotten at the argon and oxygen pressure ratio of 15:1. Then the transmittance change between colored and bleached states at a wavelength of 600nm was 25.6% and 9.5% retaled to nickel doped vanadium pentoxide and undoped films. That result indicated the doped with a small amount of nickel can actually improve the electrochromic properties of vanadium films.
Shieh, Yi-Chueh y 謝一全. "Investigation of Electrochromic Properties of Nickel-Vanadium Oxide Films Prepared by Reactive Magnetron Sputtering". Thesis, 2008. http://ndltd.ncl.edu.tw/handle/ge2akh.
Texto completo國立臺北科技大學
車輛工程系所
96
Electrochromic technology has been widely used for general applications to daily life. Novel development of electrochromic system has been made on the applications of automobile windshield and architecture windows. The smart windows can modulate light flux and control heat loadings. Applications on low power monitor or specialty filters also provide solutions for energy and cost cut. In this study, the valence mixture of nickel in Ni-V oxide films appears to affect the change of transmission rate (△T) more than oxygen concentration in the oxide thin films. The concentration of +2 and +3 valence mixture increases coloration efficiency. Films made by an optimum sputtering working atmosphere of 66.67% oxygen content demonstrate coloration efficiency of CE= 32.03 cm2/C at 550nm wavelength. After annealing at 400℃, oxygen content in the film appears to reduce. The optical band gap also reduces from 3.99eV to 3.89eV. It is proposed that the increase of oxygen vacancies causes the valence band and conduction band to approach and thus narrow the optical band gap.
Kamika, Ilunga. "Tolerance limits of selected protozoan and bacterial isolates to vanadium and nickel in wastewater systems". 2013. http://encore.tut.ac.za/iii/cpro/DigitalItemViewPage.external?sp=1000741.
Texto completoPollution of water sources with heavy metals is currently a global concern due to the detrimental effect of these metals on both human and animal health. To address this issue, biological treatment methods have been seen as the most effective and eco-friendly option of the available treatment processes of wastewater. The aim of this study was to compare the ability of selected bacterial isolates and indigenous protozoan to tolerate nickel and vanadium in wastewater systems in order to determine which group of organisms might play a major role in the removal of nickel and vanadium, even at high concentrations, in wastewater treatment systems.
Perng, Wey Bin y 彭渭濱. "A Research for Attempting to Prepare New Cathode Materials– Lithium Vanadium Nickel Mixed Metal Oxides". Thesis, 1993. http://ndltd.ncl.edu.tw/handle/65631221387250662210.
Texto completo吳其祐. "The behavior of solvent extraction with the vanadium and nickel leaching liquor from oil-fired fly ash". Thesis, 2001. http://ndltd.ncl.edu.tw/handle/14878497753434685577.
Texto completoHSU, TSUNG-HSIEN y 許宗賢. "Optimization of Nickel-Vanadium Oxide Films by Taguchi Method Combined with Intelligent Control System Applied to Electrochromic Devices". Thesis, 2019. http://ndltd.ncl.edu.tw/handle/bauw2j.
Texto completo國立金門大學
電子工程學系碩士班
107
The electrochromic film is applied to the windows of a building. When the outdoor sunlight is strong, the color of the window can be changed by controlling the potential or current, and the intensity of the sunlight passing through the window can be controlled at will and the heat is blocked. The purpose of regulating and reducing heat load is achieved to reduce energy waste. In addition to process limitations, the adhesion between electrode elements is weakened, the corrosive effect of acidic liquid electrolytes, long-term intense light irradiation, high temperature environment, electrolyte deterioration and liquid leakage, etc., all of which result in short service life and low optical density of electrochromic materials. And the reason for the slow coloring, and the auxiliary electrode nickel oxide is magnetic, requires special equipment to prepare, and is not easy to be widely used. This study proposes that the Taguchi method optimizes the electrochromic film combined with the intelligent control system, which not only solves the magnetic problem of nickel oxide. Through the integration of the Taguchi method and the rule of thumb, it is possible to greatly reduce the number of experiments and find the optimum process parameters for preparing the nickel-vanadium oxide film. According to the prediction analysis of Taguchi method, the S/N ratio is 8.20 when the original parameter sputtering power is 150W and the oxygen flow rate is 1sccm. The optimized parameter 100W 20sccm can reach the S/N ratio of 28.80, and the difference is nearly 20.60. According to XRD, SEM, electrochromic properties and optical analysis, JCPDF cards 47-1049、01-1260 and 89-7129 show that the Ni2O3 film has a polycrystalline structure, preferred orientation is Ni2O3 (111). Microstructural results show that when the oxygen flow increases, the target poisoning phenomenon will occur, resulting in a significant decrease in the deposition rate, but the surface density will be more dense. The thickness of the film is proportional to the power, inversely proportional to the oxygen flow, and the surface density is proportional to the oxygen flow. The optical analysis showed that the optimized nickel oxide vanadium film ultraviolet light (400nm), visible light (550nm), infrared light (800nm) optical modulation (ΔT) were 25.1%, 38.7%, 32%, respectively. The optical density (ΔOD) was 0.478, 0.375, and 0.249, respectively, and the coloring efficiency (CE) was 24.475, 19.201, and 12.45. Since this study is an auxiliary electrochromic layer, the electrochromic layer can be used to make up for the unstoppable light, so it is possible to find a path to find the electrochromic film with the best fading effect, and make an all-solid electrochromic film. When it is not only able to solve the problem that the nickel-vanadium oxide film cannot have both high optical modulation effect and high fading efficiency. From the results, the best parameter is 300W oxygen flow rate 20sccm. The optical modulation of ultraviolet light (400 nm), visible light (550 nm), and infrared light (800 nm) at the time of fading was 75.8%, 80.8%, and 83%, respectively, and the full spectrum was as high as 75% or more. Finally, this study will optimize the nickel oxide vanadium electrochromic film combined with the fuzzy PID control system. Through this system, the light of up to 1000Lux can converge the light illumination to the CNS standard indoor illumination of 500Lux in 8 minutes. Achieve effective control of indoor ambient light, solve the shortcomings of traditional curtains that cannot control sunlight. And the results confirmed that it can effectively block the main thermal energy infrared light in the sun, indoor blocking nearly 81.98% of infrared light, and reduce the indoor temperature from 30 degrees to 26 degrees. The research uses the Taguchi method combined with the optimization of the nickel-vanadium oxide film experiment, which can reduce the number of experiments in the traditional process, and can better combine the researcher's rule of thumb to achieve more effective optimization of the film. The results show that the Taguchi method can not only quickly find the best parameters of the process, but also effectively optimize the electrochromic film. And this study combines fuzzy PID control system. This system does not require cumbersome and high-cost hardware equipment, can achieve the purpose of regulating and reducing indoor temperature and visible light, and can reduce the energy consumption of indoor air conditioners, and achieve energy saving and carbon reduction effects.
Bower, Charles. "Stabilization/solidification treatments for filter cake, a by-product of asphaltene gasification". 2012. http://hdl.handle.net/10170/499.
Texto completoHsu, Ching-Hua y 許清樺. "Electrochemical deposition of nanostructured vanadium oxide and tin on porous nickel substrates and investigation of their energy storage performance". Thesis, 2013. http://ndltd.ncl.edu.tw/handle/30684946676915276450.
Texto completo國立中央大學
材料科學與工程研究所
101
In this study, the electrodes were prepared by electrochemical manner. In the beginning, porous nickel substrate was prepared by alloy/dealloy method in an aqueous solution containing Cu(II) and Ni(II). This material has high specific surface and uniform structure, very suitable for electrical storage devices as current collector. The first study, vanadium oxide deposited on porous Ni and explored its capacitance characteristics in 3 M KNO3 electrolyte. A porous nickel substrate compared to flat substrates, which can proof nanostructures greatly increase their capacitance value and improve the maintenance at high rate, low internal resistance leading to the overall performance significantly enhanced. The 2nd study is lithium batteries fabrication, the most widely used energy storage components. Using porous nickel with tin electrode, the absolute expansion will effectively reduce and the uniformity structure of the substrate can avoid concentration of stress. Between two kind substrates, the porous substrate exhibited higher capacitance value at high current density (15 A g-1), the capacity reached 459 mAh g-1. Although applying nano substrate is a possible way, the ionic liquid is used as the plating solution can directly deposited nanostructures give the better method. In details for the ionic liquid system, without the side reaction of electrolysis of water, the deposition efficiency can be greatly improved for further industry processes, the utilization of ionic liquid will avoid oxides and other byproducts generated in long waiting time. At the first cycle, the lithiated capacity is 863 mAh g-1 and the reversible capacity is 641 mAh g-1 (0.3 A g-1), which is comparable to those prepared in aqueous solution.
Καραμούτσος, Σπυρίδων-Διονύσιος. "Ανάπτυξη μεθόδου εξουδετέρωσης επικίνδυνων στερεών κατάλοιπων πετρελαϊκών μονάδων ηλεκτροπαραγωγής με ανάκτηση πολύτιμων κραματικών μετάλλων". 2004. http://nemertes.lis.upatras.gr/jspui/handle/10889/243.
Texto completoThe power generating installations of P.P.C. include m ore than 40 oil-fired power stations of about 2100MW total capacity. The mos t important stations are those of the interconnected system that ope rate in L avrio and Aliv e ri. The rest operate in the autonom ous system of the A eg e an islands and Cre te . M ore than 500t of solid w aste s are produce d annually during the w ashing proce sses of the air pre -he aters and the crude oil tanks of the aforementioned units w ith increasing te nden cy. These residue s are classifie d as hazardous according to the Europe an directive s. The ir neu tralizati on and safe de position is c om pulsory according to the E.U. re gulations. In the current the sis, complete characte rization of pretre ate d and untre ated re sidues was carried out. It w as found that the re sidues exa mined contained 1.6-13.4 %V and 0.8-5.5%Ni, being the refore a conside rably richer raw material than the vanadium and nickel ore deposits. For instance, the H elle nic nicke lferrous ore s, that are smelted in L arym na contain only 0.93-1.02% Ni. No organic compounds w ere de te cte d in the re sidues and the presence of vanadium was identified as VO 2. The fundam ental task of the thesis w as the de ve lopment of a method that com bine s the neutralization of the re sidue s with the recovery of the me tals containe d. The propose d me thod includes also a sinte ring stage of the untre ated residues, aiming at their agg lom e ration and e nrichm e nt in the pre cious alloying metals. The re sidues de sulphurization, de carburization and drying is achieved sim ultaneously. The sinter products contain up to 6.0% Ni and 14.7 % V, sugge sting that en richment of 8% in N i and 10 % in V w as achiev ed, with simultaneous loss of sulphur and carbon in the rates of 73 and 85% respe ctive ly. S inte ring, acts as an indigen ous process with total exploitati on of the che mical en e rgy of carbon and sulphur. It also rep re sents the first ste p for the re covery of the m etals containe d in the residues. Mo reov e r, provided the safe depo sition of the neutralize d and en riche d in valuable m e tals re sidue s, it is possible to ge ne rate a significant stock by piling m aterial from the indige nous sou rce s and imports of such residues. Thus a me tallurgical unit of m e tals re covery could operate at profit. The e valuation of the effects of the ground disposal of the investigate d solid re sidue s and sinte r produ cts is a mus t. The simulation of their le aching by rainfall wa s thus vii conducted. The hypothesis of the unreacted core mode l see ms to describe the proce ss ade que ntl y. The mode l constants and its complete m e chanism we re de te rmined and confirm ed expe rimentall y. Initially chem ical re action se ems to be the rate-de te rmining ste p for the transfe r of me tals in the liquid phase. W ith the e lution prog re ss the me chanism is controlled by diffusion phenomen a. The prediction of the long -te rm effects of the ground de position of the untre ate d and sinte red residue s w as att empted by applying the sugge sted models . It was shown that substantia l amount of time, 10 ye ars minim um, is ne e de d for the drop of the m e tals conce ntrations in the leachate to allowa ble lev e ls. The final stage of the proposed method contains the red uction smelting of the re sidues. A serie s of tests w as conducted in graphite crucibles in Tam mann furnace. The metal oxides re duction proce ss w as investi gated and the the rmod ynamic equilibrium of the hete rogen e ous actions betw e en liquid slag and me tal w as de te rmined in tempe ratures ranging from 1375 to 1600 oC. The therm od ynam ic equilibria functions conce rning the nickel, vanadium and iron oxides w ere exper ime ntally dete rmined. The e xpe rimental test heats yie lded final me tals recove ry rates of 85-98% for Ni and 78-95% for V , with simultaneous production of ne utralized slag suitable for deposition or othe r usage . The conditions that ma ximize the Ni and V re cove ries according to the expe rime ntal findi ngs we re: the high tempe ratures the use of graphite crucible the Fe S i addi tions as re ductant In contrast to the dominating opinion, it w as shown that high rec ove ry rate s w e re achieved in high basicity rates of CaO/Si O 2>2, ensuring the re fractory lining of the furnace and the furthe r use of the produced slag. Alternatively, the direct re duction smelting of the physicochemic ally pretre ated re sidues was inve stigated. The finding that the small a dditions up to 10 % of boe hm itic type of bauxite improve the rec ove ries of nickel and in rate s highe r than 98% is ve ry important. The kinetics of the redu ction of iron and vanadium oxide s from the slag to the iron bath w ere also inve sti gate d and the corresponding constants and rate de te rmining ste ps we re de te rmined. viii A holisti c method of recycling the solid residue s of the oil-fire d stati ons is propose d The propose d me thod, in addition to high re cove ry rate s of the valuable alloying eleme nts containe d (nickel and vanadium) avoids the re sidue s treatment with expe nsive neutralization me thods. Mo reov e r, the ne utralization of these hazardous ma terials is achiev ed w ith substantial financial profit from the me tals re cove ry at the same time.
Müller, Sven. "Structural and optical impact of transition metal implantation into zinc oxide single crystals and nanowires". Doctoral thesis, 2009. http://hdl.handle.net/11858/00-1735-0000-0006-B487-7.
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