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1
Lu, Haijun, Qian Zhang, Yiqie Dong, Jixiang Li y Xiong Zhang. "The Adsorption Capacity, Pore Structure, and Thermal Behavior of the Modified Clay Containing SSA". Advances in Materials Science and Engineering 2016 (2016): 1–7. http://dx.doi.org/10.1155/2016/9894657.
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Sewage sludge ash (SSA) was created by burning municipal sludge. The potential of clay containing 1 or 3 or 5% SSA was assessed for use as a landfill liner-soil material. Batch adsorption, low temperature N2adsorption, and TG-DTA tests were performed to evaluate the adsorption capacity, micropore structure, thermostability, and components of soils under Cr(VI) and Pb(II) chemical solutions. With the increasing amount of SSA in modified clay, the adsorption capacity of Cr(VI) and Pb(II) to the modified clay increases gradually. After absorption, the pore size of modified clay ranges from 2 nm to 8 nm. With the increasing amount of absorption, the pore volume decreases and the specific surface area increases. With the increasing of adsorption concentration of Cr(VI) and Pb(II), the mass loss percentage of modified clay increases to 23.4% and 12.6%, respectively. The modified clay containing SSA may be used as a good barrier material to attenuate contamination of Cr(VI) and Pb(II) in landfills.
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Novitasari, Sholihah, Sriatun Sriatun y Taslimah Taslimah. "Aluminum Pillared Clay (Al-PILC) for Adsorption of Dyes in Red Fruit Oil". Jurnal Kimia Sains dan Aplikasi 24, n.º 1 (8 de febrero de 2021): 9–14. http://dx.doi.org/10.14710/jksa.24.1.9-14.
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Red fruit oil contains carotene, which is dark orange, so it is not very popular. Therefore, it is necessary to reduce the intensity of the color. Yesterday, in this study, the synthesis and characterization of Al-pillared clay (Al-PILC) from light and heavy clay fractions were carried out. The absorption capacity of red fruit carotene dyes was studied. The research stages included preparation, fractionation, activation, pillarization of clay with aluminum, characterization, and adsorption test for carotene dyes on red fruit. Characterization was carried out using X-ray Diffractometer (XRD) and Gas Sorption Analyzer (GSA). The results showed that basal spacing of natural clay, Al pillared heavy fraction-clay, Al pillared light fraction-clay, activated light fraction were 15.08 Å, 15.27 Å, 16.84 Å, and 16, respectively. 22 Å. The GSA results showed that the surface area and pore volume of the Al pillared light fraction-clay of 0.3 was higher than the heavy fraction. The average pore size of Al pillared light fraction-clay and the heavy fraction was found in the mesoporous range of 30-100 Å, and the adsorption isotherm is type IV. Al-pillared light fraction-clay had higher adsorption ability than a heavy fraction and light fraction before pillaring. When the pillaring agent’s concentration was 0.3 M, Al pillared heavy fraction-has absorption capacity is 58.66%, while Al pillared light fraction-clay is 90.4%.
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Xu, Hui, Dong Hong Guo y Yao Xu. "Removal of Cu(II) Ions from Aqueous Solution by KH-570 Modified Attapulgite Clay". Advanced Materials Research 320 (agosto de 2011): 275–79. http://dx.doi.org/10.4028/www.scientific.net/amr.320.275.
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Attapulgite clay (ATP) was modified by Silane coupling agent (KH-570) to creat more efficient sites for Cu(II) adsorption. The natural and KH-570 modified attapulgite clay were characterized by Fourier transform infrared spectrometer (FTIR) and SEM. The effects of various experimental parameters such as the amount of modifier, the quality of KH-570 modified ATP, adsorption time, adsorption temperature on Cu(II) adsorption onto KH-570modified ATP were studied in detail. The results showed that the 30% of modifier (The quality of the modifier mass fraction attapulgite) had the best adsorption capacity. When the dosage of modified attaplgite clay was 0.5g and the absorption time was 240min under 20°C, the adsorption rate of Cu(II) in wastewater approached 97%. Meanwhile, the type of absorption was Langmuir isotherm. Desorption experiments showed that the adsorption mechanism of KH-570 modified ATP to Cu(II) was the chemical adsorption.
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Wang, Hongyan, Shangwen Zhou, Jiehui Zhang, Ziqi Feng, Pengfei Jiao, Leifu Zhang y Qin Zhang. "Clarifying the Effect of Clay Minerals on Methane Adsorption Capacity of Marine Shales in Sichuan Basin, China". Energies 14, n.º 20 (19 de octubre de 2021): 6836. http://dx.doi.org/10.3390/en14206836.
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The effect of clay minerals on the methane adsorption capacity of shales is a basic issue that needs to be clarified and is of great significance for understanding the adsorption characteristics and mechanisms of shale gas. In this study, a variety of experimental methods, including XRD, LTNA, HPMA experiments, were conducted on 82 marine shale samples from the Wufeng–Longmaxi Formation of 10 evaluation wells in the southern Sichuan Basin of China. The controlling factors of adsorption capacities were determined through a correlation analysis with pore characteristics and mineral composition. In terms of mineral composition, organic matter (OM) is the most key methane adsorbent in marine shale, and clay minerals have little effect on methane adsorption. The ultra-low adsorption capacity of illite and chlorite and the hydrophilicity and water absorption ability of clay minerals are the main reasons for their limited effect on gas adsorption in marine shales. From the perspective of the pore structure, the micropore and mesopore specific surface areas (SSAs) control the methane adsorption capacity of marine shales, which are mainly provided by OM. Clay minerals have no relationship with SSAs, regardless of mesopores or micropores. In the competitive adsorption process of OM and clay minerals, OM has an absolute advantage. Clay minerals become carriers for water absorption, due to their interlayer polarity and water wettability. Based on the analysis of a large number of experimental datasets, this study clarified the key problem of whether clay minerals in marine shales control methane adsorption.
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Yermiyahu, Z., I. Lapides y S. Yariv. "Visible absorption spectroscopy study of the adsorption of Congo Red by montmorillonite". Clay Minerals 38, n.º 4 (diciembre de 2003): 483–500. http://dx.doi.org/10.1180/0009855033840110.
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AbstractThe adsorption of the anionic dye Congo Red (CR) by Na-, Cs-, Mg-, Cu-, Al- and Fe-montmorillonite was investigated by electronic spectroscopy. Spectra of the aqueous suspensions of different clay concentrations and different loadings were recorded. The spectra were curve fitted and were compared to spectra of aqueous solutions of CR at different pH values. Four bands representing anionic varieties and two representing protonated varieties of CR were identified in spectra of CR-treated Na-, Cs-, Mg-, Cu- and Al-montmorillonite. Spectra of CR-treated Femontmorillonite were slightly different, showing three bands representing anionic varieties and four representing protonated CR. The ratio between areas of bands, which represent the protonated varieties, and those representing the anionic varieties were determined showing correlation with the acidity of the metallic cation. The clay in the aqueous suspensions became coloured after the adsorption of CR. The following stainings were obtained, Na- and Mg-clay, red, Cs-clay, violet-red, Cu-clay, reddish-violet, Al-clay, dark violet and Fe-clay, dark blue. It appears that CR can serve as an indicator of the surface acidity of montmorillonite. The effects of aging on the sorption of the dye and on the surface-acidity of the CR-clay complex were investigated.
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Jasmin Shah, Jasmin Shah, Muhammad Rasul Jan Muhammad Rasul Jan, Mian Muhammad Mian Muhammad y Behisht Ara and Changeez Ahmad Behisht Ara and Changeez Ahmad. "Organo-Clay as Adsorbent for Removal of Fenoxaprop-p-ethyl from Water Samples; A Statistical Approach". Journal of the chemical society of pakistan 43, n.º 3 (2021): 278. http://dx.doi.org/10.52568/000575/jcsp/43.03.2021.
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In this study, fuller’s earth (FE) modified with sodium dodecylbenzene sulphonic acid was used for adsorptive removal of fenoxaprop-p-ethyl (FPE) herbicide from water samples and statistical validation of the experimental observations was accomplished. All the adsorption experiments were conducted in batch mode. The effect of pH, agitation time, adsorbent dose and initial herbicide concentration on adsorption process was studied. About 98.5% adsorption efficiency was achieved at initial analyte concentration of 1000 mg L-1 at pH 6 within 60 min at adsorbent dose of 0.1 g. The adsorption kinetics were studied and pseudo-second-order kinetic model was found to follow the adsorption kinetics with R2=0.998. The isotherm studies show that the adsorption data fit well to the Freundlich isotherms. In statistical evaluation, the individual as well as the interaction effect of various factors on adsorption was investigated and it was found that concentration, pH and adsorbent dose are the significant factors with p values of 0.0001, 0.004 and 0.006 respectively, while contact time was found statistically insignificant having p value greater than 0.05. The coefficient of determination (R2=0.930) shows that % adsorption is highly dependent on the studied factors and their interactions. Under the optimized set of conditions, high absorption capacity of 200.22 mg g-1 was achieved.
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Jasmin Shah, Jasmin Shah, Muhammad Rasul Jan Muhammad Rasul Jan, Mian Muhammad Mian Muhammad y Behisht Ara and Changeez Ahmad Behisht Ara and Changeez Ahmad. "Organo-Clay as Adsorbent for Removal of Fenoxaprop-p-ethyl from Water Samples; A Statistical Approach". Journal of the chemical society of pakistan 43, n.º 3 (2021): 278. http://dx.doi.org/10.52568/000575.
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In this study, fuller’s earth (FE) modified with sodium dodecylbenzene sulphonic acid was used for adsorptive removal of fenoxaprop-p-ethyl (FPE) herbicide from water samples and statistical validation of the experimental observations was accomplished. All the adsorption experiments were conducted in batch mode. The effect of pH, agitation time, adsorbent dose and initial herbicide concentration on adsorption process was studied. About 98.5% adsorption efficiency was achieved at initial analyte concentration of 1000 mg L-1 at pH 6 within 60 min at adsorbent dose of 0.1 g. The adsorption kinetics were studied and pseudo-second-order kinetic model was found to follow the adsorption kinetics with R2=0.998. The isotherm studies show that the adsorption data fit well to the Freundlich isotherms. In statistical evaluation, the individual as well as the interaction effect of various factors on adsorption was investigated and it was found that concentration, pH and adsorbent dose are the significant factors with p values of 0.0001, 0.004 and 0.006 respectively, while contact time was found statistically insignificant having p value greater than 0.05. The coefficient of determination (R2=0.930) shows that % adsorption is highly dependent on the studied factors and their interactions. Under the optimized set of conditions, high absorption capacity of 200.22 mg g-1 was achieved.
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Hoving, Alwina L., Melanie A. Münch, Christophe Bruggeman, Dipanjan Banerjee y Thilo Behrends. "Kinetics of selenite interactions with Boom Clay: adsorption–reduction interplay". Geological Society, London, Special Publications 482, n.º 1 (2019): 225–39. http://dx.doi.org/10.1144/sp482-2018-60.
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AbstractThe speciation of selenium (Se) in clay-rich host rocks is important within the framework of geological disposal of radioactive waste since it affects its migration. Removal of selenite from formation water can be caused by reduction and adsorption. Reduction could potentially be inhibited or delayed by adsorption. Here, the interplay of adsorption and reduction of selenite was investigated in batch experiments with Boom Clay and its separated size fractions. In all experiments, dissolved Se concentrations (Seaq) showed a fast initial decrease that was followed by a slower decline until removal was almost complete. X-ray absorption spectroscopy indicated that adsorption of selenite accounted for the fast removal of Seaq followed by slower selenite reduction. Eventually, almost all solid-bound SeIV became reduced to Se0 in all experiments. The progress of Seaq removal and SeIV reduction to Se0 could be described by a kinetic model involving reversible adsorption on clay minerals and reduction by pyrite. This implies that the reduction of selenite to Se0 is not significantly hindered or delayed by selenite adsorption on clay minerals. Pyrite is probably the most relevant reductant for selenite in Boom Clay, although reduction by FeII structurally bound in clay minerals might provide an additional pathway for selenite reduction in clay rocks.
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Râpă, Maria, Anca Andreea Ţurcanu, Ecaterina Matei, Andra Mihaela Predescu, Mircea Cristian Pantilimon, George Coman y Cristian Predescu. "Adsorption of Copper (II) from Aqueous Solutions with Alginate/Clay Hybrid Materials". Materials 14, n.º 23 (25 de noviembre de 2021): 7187. http://dx.doi.org/10.3390/ma14237187.
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Massive amounts of industrial and agricultural water around the world are polluted by various types of contaminants that harm the environment and affect human health. Alginic acid is a very versatile green polymer used for heavy metal adsorption due to its availability, biocompatibility, low cost, and non-toxic characteristics. The aim of this paper was to prepare new low-cost hybrid composite beads using sodium alginate with treated montmorillonite and kaolin for the adsorption of copper (Cu) cations. Modified and unmodified clays were investigated by studying their morphology and elemental composition, functional groups, and mean particle size and particle size distribution. The characterization of alginate/clay hybrid composite beads was carried out by evaluating surface morphology (by scanning electron microscopy, SEM), crystallinity (by X-ray diffraction, XRD), and point of zero charge (pHpzc)(Zeta Potential Analyzer). Batch adsorption experiments of alginate/clay hybrid composite beads investigated the effect of metal concentration in the range of 1–4 mg L−1 on Cu(II) removal, adsorption kinetic for maximum 240 min, and Langmuir and Freundlich adsorption isotherms by using atomic absorption spectrometry. The pseudo-second-order kinetic model best fitted the adsorption for alginate/montmorillonite beads (R2 = 0.994), while the diffusion process was predominant for montmorillonite/kaolin beads (R2 = 0.985). The alginate/clay hybrid materials best fitted the Langmuir isotherm model.
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Sasria, Nia, Aprina Dewi Rizki y Gusti Umindya Nur Tajalla. "Removal of Lead Ions (Pb<sup>2+</sup>) Using Acid-Activated Clay from East Kalimantan". Materials Science Forum 1076 (8 de diciembre de 2022): 91–100. http://dx.doi.org/10.4028/p-es4k1t.
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This study aims to determine the optimal conditions of acid-activated clay adsorbent in adsorption of Pb2+ metal ions. Clay was taken around East Kalimantan, Karang Joang. This adsorbent was prepared by mixing clay into a solution of KMnO4, H2SO4 and HCl successively, and stirred for 4 hours at a temperature of 80°C. The morphology and active groups of the adsorbent were analyzed using BET and FTIR. The variables of this study were the mass of the adsorbent 0.1, 0.3 and 0.5 grams and the contact time of 5, 30 and 55 minutes. Adsorption capacity of this adsorbent was analyzed using Atomic Absorption Spectrophotometry (AAS). The results of this study indicate that the optimum mass of adsorbent is 0.1 g, and contact time is 30 minutes. Adsorption capacity of Pb2+ metal ions by acid-activated clay adsorbent at the optimum condition of 0.1 gram was 23,585 mg/g and adsorption energy was 2,338 kJ/mol. Meanwhile, at the optimum condition for 30 minutes, the adsorption capacity was 0.771 mg/L, and the adsorption energy was 2.895 kJ/mol. So that the adsorption process in this study can be known, namely physical adsorption because the adsorption energy value is less than 40 kJ/mol.
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Aisa, C., R. A. Alvarez-Puebla, J. Blasco, J. C. Echeverría y J. J. Garrido. "Combining DLS, XRD, SEM-EDAX and EXAFS in the study of Zn(II) retention on a palygorskitic clay". Clay Minerals 40, n.º 2 (junio de 2005): 205–12. http://dx.doi.org/10.1180/0009855054020166.
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AbstractClay materials play a key role in determining the retention capacity of a soil, and are widely used in waste treatments. One of the most commonly used clays is palygorskite. The aim of this research is to determine the chemical species formed by Zn when retained in a palygorskitic clay material. Adsorption isotherm analysis is useful in studying the retention process, because it provides a macroscopic view of the retention phenomena. Complementary techniques are needed in order to study the different retention processes. Sorption isotherms of Zn on palygorskitic clay were carried out; the supernatant was analysed by means of dynamic light scattering (DLS) and the residues by using X-ray diffraction (XRD), scanning electron microscopy-energy dispersive angle X-ray (SEM-EDAX)analysis and extended X-ray absorption fine structure (EXAFS). Isotherm analysis shows that the global retention process could be due to the sum of two separate processes, adsorption and surface precipitation via solid-solution. This is supported by DLS, which shows that ζ potential increases as the Zn(II) is retained onto clay surfaces but remains constant during the precipitation process. The XRD pattern corresponding to the Zn-clay system showed weak new peaks, probably from zincite. The microanalysis by X-ray fluorescence of several spots selected for their different electronic densities indicated that the retained Zn was randomly distributed across the clay surface. Analysis by EXAFS supports the hypothesis of retention via adsorption and solid-solution surface precipitation.
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Kim, Hyesu, Jaehyung Yu, Lei Wang, Yongsik Jeong y Jieun Kim. "Variations in Spectral Signals of Heavy Metal Contamination in Mine Soils Controlled by Mineral Assemblages". Remote Sensing 12, n.º 20 (9 de octubre de 2020): 3273. http://dx.doi.org/10.3390/rs12203273.
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This paper illustrates a spectroscopic analysis of heavy metal concentration in mine soils with the consideration of mineral assemblages originated by weathering and mineralization processes. The mine soils were classified into two groups based on the mineral composition: silicate clay mineral group (Group A) and silicate–carbonate–skarn–clay mineral group (Group B). Both soil groups are contaminated with Cu, Zn, As, and Pb, while the contamination level was higher for Group A. The two groups exhibit different geochemical behaviors with different heavy metal contamination. The spectral variation associated with heavy metal was highly correlated with absorption features of clay and iron oxide minerals for Group A, and the absorption features of skarn minerals, iron oxides, and clay minerals for Group B. It indicates that the geochemical adsorption of heavy metal elements mainly occurs with clay minerals and iron oxides from weathering, and of skarn minerals, iron oxides, and clay minerals from mineralization. Therefore, soils from different secondary mineral production processes should be analyzed with different spectral models. We constructed spectral models for predicting Cu, Zn, As, and Pb in soil group A and Zn and Pb in soil group B using corresponding absorptions. Both models were statistically significant with sufficient accuracy.
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Mao, Cui Ping y Shu Bin Wu. "Adsorption of Polyvinyl Acetate (PVAc) Adhesive Emulsion from Aqueous Solution by Lignin-Phenol Based Cationic Surfactant Modified Organic Kieselguhr". Applied Mechanics and Materials 472 (enero de 2014): 861–66. http://dx.doi.org/10.4028/www.scientific.net/amm.472.861.
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The kieselguhr was modified by the lignin-based cationic surfactant which obtained from the Mannich reaction. Modified organic kieselguhr exhibited favorable adsorption to adhesive and fine colloidal substance. Dissolved and colloidal substances (DCS) appeared in the secondary fibre reuse process interfered the pulping and papermaking seriously. The organic clay could remove the stickies substances through adsorption approach technically. In this paper, PVAc was chosen as the simulacrum of stickies because of its wide application as the adhesives in wood, textile, paint, paper processing and other industries. The organic kieselguhr was characterized by scanning electron microscope (SEM) and infrared spectrum (IR), etc. Then the adsorption experiment of PVAc emulsion from aqueous solution was carried out. 78.61% of the adhesive was absorbed by the organic kieselguhr, while the untreated clay only removed 53.41%. Common cationic surfactant, such as dodecyl trimethyl ammonium bromide (DTAB) and cetyl trimethyl ammonium bromide (CTAB), the modified clays were taken as the reference substance. The results indicated that the modified organic kieselguhr had well absorption efficacy to the stickies simulacrum, which provided a novel approach for the stickies controlling.
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Smail, Heman A., Kafia M. Shareef y Zainab H. Ramli. "An Eco-Friendly Process for Removal of Lead from Aqueous Solution". Modern Applied Science 11, n.º 5 (8 de abril de 2017): 47. http://dx.doi.org/10.5539/mas.v11n5p47.
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The adsorption of lead (Pb II) ion on different types of synthesized zeolite was investigated. The BET surface area, total pore volume & average pore size distribution of these synthesized zeolites were determined by adsorption isotherms for N2, the surface area & total pore volume of their sources were found by adsorption isothermN2.The adsorption equilibrium was measured after 24h at room temperature (RT) & concentration 10mg.L-1 of Pb (II) was used. The adsorption of heavy metal Pb (II) on four different prepared zeolites (LTA from Montmorillonite clay, FAU(Y)-B.H (G2) from Barley husk, Mordenite (G1) from Chert rock, FAU(X)-S.C (G3) from shale clay & modified Shale clay by oxalic acid (N1) & sodium hydroxide (N2)), were compared with the adsorption of their sources by using static batch experimental method. The major factors affecting the heavy metal ion sorption on different synthesized zeolites & their sources were investigated. The adsorption equilibrium capacity (Qm) of Pb (II) ion for different synthesized zeolites ordered from (N1>N2>LTA>G3>G2>G1&for their sources ordered Shale clay >Montmorilonite> Barley husk>Chert rock. The atomic absorption spectrometry was used for analysis of lead heavy metal ion, the obtained results in this study showed that the different synthesized zeolites were efficient ion exchanges for removing heavy metal, in particular, the modified zeolite from shale clay by oxalic acid.
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Kaewtabut, Yutthana, Wansika Sirimongkol, Adisak Thueploy y Siriphan Nilpairach. "Utilization of Rice Husk Ash and Waste Sludge from Cutting Glass Manufacturing with Angthong Pottery". Key Engineering Materials 608 (abril de 2014): 103–7. http://dx.doi.org/10.4028/www.scientific.net/kem.608.103.
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Efficiently utilization of rice husk ash (RHA) and waste sludge from cutting glass manufacturer (WSG) as additives to pottery clay would yield positive economic impacts, such as more friendly industrial ecosystems. In this study, The RHA and WSH were used as additives to Angthong pottery clay (APC) and casting and fired properties were examined. Two sets of sample with a mixture consisting of 60% APC, 20% RHA, and 20% WSG (CRG formula) and non-added clay (C100 formula) were prepared by slip casting technique. Samples were fired at temperature 900 °C and 1100°C; then the viscosity of slurry, linear shrinkage, water adsorption, and 3-point bending strength were measured. The results showed that the optimum viscosity for slip casting of CRG and C100 were 1638 cP and 983 cP, respectively. The water adsorptions of all samples decrease while their shrinkage and strength increase with temperature. At 900°C, the water adsorption and the strength of CRG were 32% and 1184 psi, respectively. Comparatively, CRG’s water absorption was 1.5 times higher than C100’s, while their mechanical strength was insignificantly different. This due to the RHA behaves as pore forming and the WSG promotes the sintering of samples.
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Nishina, Haruka, Shota Hoshino, Yuta Ohtani, Tamao Ishida, Tetsuya Shimada y Shinsuke Takagi. "Anisotropic energy transfer in a clay–porphyrin layered system with environment-responsiveness". Physical Chemistry Chemical Physics 22, n.º 25 (2020): 14261–67. http://dx.doi.org/10.1039/d0cp02263b.
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The adsorption orientation behavior of tetrakis(1-methylpyridinium-3-yl)porphyrin (m-TMPyP) and p-TMPyP on the clay monolayer prepared by the Langmuir Blodgett (LB) technique was investigated using the absorption and dichroic spectra obtained on a waveguide.
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Hirade, Yugo, Tamao Ishida, Tetsuya Shimada y Shinsuke Takagi. "Adsorption and absorption behavior of cationic porphyrin on titania and clay nanosheets". Colloids and Surfaces A: Physicochemical and Engineering Aspects 624 (septiembre de 2021): 126747. http://dx.doi.org/10.1016/j.colsurfa.2021.126747.
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Li, Ding Long, Jing Si Tian, Hou Hu Zhang, Yi Min Zhang y Yue Xiang Gao. "Kinetic Study on Phosphorus Adsorption, Phosphorus Desorption, Nitrification, and Denitrification by Using Mineralized Refuse". Advanced Materials Research 340 (septiembre de 2011): 461–66. http://dx.doi.org/10.4028/www.scientific.net/amr.340.461.
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The mineralized refuse has a well particle size distribution and is similar asirregularly polyhedron with the high contents of Fe, Al, and Ca, which might be thephosphorus pool. The absorption and desorption of phosphorus, nitrification, and denitrification in the mineralized refuse and clay has been investigated by using batch incubation, respectively. The variation of phosphorous adsorption in the mineralized refuse and clay is fitted the Langmuir isotherm equation. The maximum phosphorus adsorption capacity in the mineralized refuse calculated based on the Langmuir isotherm equation is 2914 mg kg-1. Both the maximum adsorption capacity and adsorption rate of phosphorus in the mineralized refuse are over 2.0-fold more than that of the clay. The desorption rate of phosphorus in the mineralized refuse is only about 30%. NH4+-N contents in the mineralized refuse samples fell from 129 mg N kg-1 to 83.0 mg N kg-1 within the first 24 h during the nitrification process. Accordingly, the NO3--N content in the mineralized increased from 137 mg N kg-1 to 170 mg N kg-1. While the decrease of NH4+-N contents and the increase of NO3--N contents in the clay was only 1/2 and 1/6 as large as in the mineralized refuse, respectively. During the denitrification process, the K-value of the fitted zero-order kinetics for NO3--N denitrification in the mineralized refuse was 6.5-fold higher than in the clay.
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Nadziakiewicza, Kehoe y Micek. "Physico-Chemical Properties of Clay Minerals and Their Use as a Health Promoting Feed Additive". Animals 9, n.º 10 (23 de septiembre de 2019): 714. http://dx.doi.org/10.3390/ani9100714.
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The contamination of feeds with microbiological or toxicological agents can affect health, productivity and safety of livestock animals and their products. The treatment of feedstuffs to lower the content of undesired substances before feeding is expensive and labor intensive, therefore an alternative is to reduce their gastrointestinal absorption. Different feed additives are available, however the use of clays and clay minerals are ideal for this purpose due to their high specific surface area, adsorption capacity, low or null toxicity for the animal and low cost. A large number of clays available to producers have different structures that are dependent on their mining source, causing difficulty in proper categorization. For this reason properties of phyllosilicates with 1:1 layers (one sheet of SiO4 tetrahedra joined to one sheet of Al- or Mg-octahedra), 2:1 layers (one sheet of Al- or Mg-octahedra between two sheets of Si-tetrahedra), and 2:1:1 layers (a basic 2:1 structure with an interlayer brucite (with cations Mg2+ or Fe2+) or gibbsite (with cation Al3+) sheet) and tectosilicates are described. The role of clay minerals in animal production shows a reduction in diarrhea, better feed conversion ratio, and improved health of many livestock species due to their specific adsorption potential of many feed mycotoxins. Overall, there is growing interest in the use of clays due to their beneficial characteristics, absence of primary toxicity and success in research to reduce animal disease and improve animal production and safety of animal products.
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Ogunmodede, O. T., O. L. Adebayo y A. A. Ojo. "Enhancing Adsorption Capacity of Clay and Application in Dye Removal from Waste Water". International Letters of Chemistry, Physics and Astronomy 39 (octubre de 2014): 35–51. http://dx.doi.org/10.18052/www.scipress.com/ilcpa.39.35.
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Natural clay has been considered as a potential absorbent for removing pollutants from water and waste water. Nonetheless, the effective application of clay for water treatment is limited due to small surface area and presence of net negative surface charge, leading to it low adsorption capacity. The absorption capacity was boosted via intercalation of CaO derived from snail shell (SS). The methylene blue sorption potential, PZC, and the surface area of unmodified clay sample were substantially enhanced by the intercalation process. The process of sorption of MB from solution was analyzed using five different isotherm models (Langmuir, Freundlich, Temkin, Harkins-Jura, and Halsey isotherm equations). The value of the Langmuir monolayer sorption capacity qm (mg/g) increased from 50.12 to 88.71, PZC values increased from 4.50 to 7.40, and the surface area (m2/g) value increased from 27 m2/g to 123 m2/g after the intercalation process. The experimental data were fitted into two kinetic models: Lagergren pseudo-first order and the chemisorptions pseudo-second order. It was observed that chemisorptions pseudo-second order kinetic model described the sorption process with high coefficients of determination (r2) better than pseudo first other kinetic models. The modification caused no change in the clay surficial microstructure but increased the lattice spacing of the clay framework.
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Ogunmodede, O. T., O. L. Adebayo y A. A. Ojo. "Enhancing Adsorption Capacity of Clay and Application in Dye Removal from Waste Water". International Letters of Chemistry, Physics and Astronomy 39 (2 de octubre de 2014): 35–51. http://dx.doi.org/10.56431/p-8rzvmp.
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Natural clay has been considered as a potential absorbent for removing pollutants from water and waste water. Nonetheless, the effective application of clay for water treatment is limited due to small surface area and presence of net negative surface charge, leading to it low adsorption capacity. The absorption capacity was boosted via intercalation of CaO derived from snail shell (SS). The methylene blue sorption potential, PZC, and the surface area of unmodified clay sample were substantially enhanced by the intercalation process. The process of sorption of MB from solution was analyzed using five different isotherm models (Langmuir, Freundlich, Temkin, Harkins-Jura, and Halsey isotherm equations). The value of the Langmuir monolayer sorption capacity qm (mg/g) increased from 50.12 to 88.71, PZC values increased from 4.50 to 7.40, and the surface area (m2/g) value increased from 27 m2/g to 123 m2/g after the intercalation process. The experimental data were fitted into two kinetic models: Lagergren pseudo-first order and the chemisorptions pseudo-second order. It was observed that chemisorptions pseudo-second order kinetic model described the sorption process with high coefficients of determination (r2) better than pseudo first other kinetic models. The modification caused no change in the clay surficial microstructure but increased the lattice spacing of the clay framework.
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Márquez, Carmen Omaira, Víctor Julio García, Jefferson Raúl Guaypatin, Francisco Fernández-Martínez y Anita Cecilia Ríos. "Cationic and Anionic Dye Adsorption on a Natural Clayey Composite". Applied Sciences 11, n.º 11 (31 de mayo de 2021): 5127. http://dx.doi.org/10.3390/app11115127.
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One of the main challenges for environmental sciences today is the effective treatment of dye-laden industrial effluents. This work aimed to study the potential of an untreated (natural occurring clayey composite) red clay (RC) for the adsorption of a cationic dye Basic Navy Blue 2RN (CNB) and anionic dye Drimaren Yellow CL-2R (ADY). We evaluated the effect of pH, dye concentration, and adsorbent concentration on the removal effectiveness to study the absorption process. Also, we studied the adsorption process by analyzing the feasibility of several known adsorption isotherms and kinetic models. The results show that at a pH of less than 4, the CNB and ADY removal percentages were 97% and 96%, respectively. At a pH greater than 8, the CNB and ADY removals were 75% and 25%, respectively. The CNB adsorption happened by chemisorption of a monolayer on iron-containing particles (IPs). In congtrast, the ADY adsorption occurred by monolayer physisorption on kaolinite particles (KPs) and Na, K-rich Laumontite particles (LPs). The Langmuir isotherm model fits very well with CNB experimental data. The Temkin model shows the best fit between the isotherm function and the ADY dye-adsorption data. The pseudo-second-order kinetic model fits the CNB and ADY dye-adsorption data on RC particles. The heterogeneous composition of naturally occurring clay favors different adsorption mechanisms and opens an avenue for the separation process’s engineering.
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Shishkin, Andrei, Austris Laksa, Viktoria Shidlovska, Zane Timermane, Hakim Aguedal, Viktor Mironov y Jurijs Ozolins. "Illite Clay Ceramic Hollow Sphere - Obtaining and Properties". Key Engineering Materials 721 (diciembre de 2016): 316–21. http://dx.doi.org/10.4028/www.scientific.net/kem.721.316.
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This work focuses on clay ceramic hollow spheres (CCHS) preparation using Liepa clay and sacrificial template method in a lab scale device and testing of their properties. Water retention and compression strength were investigated in order to found out if obtained CCHS can be used as an additive for improving soil resilience.The synthesis and characterization of CCHS using expanded polystyrene spheres (EPS) as sacrificial template is presented. CCHS were fired at five different temperatures and their compressive strength, water retention, bulk density, material density, water absorption, phase composition, surface morphology, porosity using hydrostaticweighing and BET nitrogen adsorption methods, were determined.Study of clay ceramic hollow sphere structure and surface morphology revealed that all samples have spherical shape. These spheres have several pronounced protrusions from the granulation process. Clay ceramic hollow spheres have porosity rate of 21 - 36% and a water absorption rate of 15 -33%. The highest rate of porosity and water absorption was observed for hollow spheres fired at 1050°C.The increase of clayceramic hollow spheresfiringtemperature led to decrease of specific surface area-thehighestvaluewas observed at950°C and the lowest at 1150°C. The bulk density increased at 1150°C.Mechanicalstrength test of ceramic hollowspheres(HS)revealedthat with the increase of scorchingtemperature the compression strength of the spheres increasedas well.The sphere hollowshadpractically globular shape with the averagewallthickness of0,6 mm, whichcomprises10-13% ofthe outer diameter.The obtained clay ceramic hollow spheres are proposed as water retention agent.
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Chang, Po-Hsiang, Wei-Teh Jiang, Binoy Sarkar, Wendong Wang y Zhaohui Li. "The Triple Mechanisms of Atenolol Adsorption on Ca-Montmorillonite: Implication in Pharmaceutical Wastewater Treatment". Materials 12, n.º 18 (5 de septiembre de 2019): 2858. http://dx.doi.org/10.3390/ma12182858.
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The adsorption of atenolol (AT) from aqueous solutions by Ca-montmorillonite (SAz-2) was investigated in batch studies under different physicochemical conditions. The AT existed in neutral un-dissociated form at pH 10, and was adsorbed on dioctahedral smectite (SAz-2) obeying the Langmuir isotherm with a maximum adsorption capacity of 330 mmol/kg. The kinetic adsorption suggested that both strong and weak adsorption sites existed on SAz-2 and participated in the adsorption mechanisms. The amount of exchangeable cations desorbed from SAz-2 during AT adsorption was linearly correlated with the amounts of adsorbed AT having slopes of 0.43, which implied that a cation exchange based adsorption mechanism was also in place. A comprehensive basal spacing change of SAz-2 was observed after AT adsorption on the clay mineral when tested with or without AT recrystallization. The intercalation of AT into the SAz-2 interlayers did not result in swelling due to the low adsorption capacity of the drug. Prominent interactions between the pharmaceutical molecule and SAz-2 were evidenced by apparent shifts of the infrared absorption bands after adsorption. The interlayer configurations and hydrogen bonding of AT on SAz-2 were also supported by infrared, X-ray diffraction and thermogravimetric analyses. This study suggested that SAz-2 is an excellent material to remove not only AT from pharmaceutical wastewater, but can potentially remove many other β-receptor blocker drugs. The results helped us to understand the possible interlayer configurations and adsorption mechanisms of the drugs on natural clay mineral based adsorbents.
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Cosin, Shirley, Carolina A. Pinto, P. Souza Santos y Francisco Rolando Valenzuela-Díaz. "Complex Carbon-Mineral Sorbents from Common Clay". Materials Science Forum 498-499 (noviembre de 2005): 734–39. http://dx.doi.org/10.4028/www.scientific.net/msf.498-499.734.
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Carbon/mineral complexes are materials with surfaces covered partially or totally by carbon materials contains. They have high industrial potential uses as material adsorbents and ceramic filters. The objective of this work is to evaluate the corrosion strength in acid and alkaline solutions, and the adsorption capacity of methylene blue of some materials prepared in the LMPSol. The compositions were prepared with an industrial common clay named “taguá” and organic and inorganic additives from industrial residues up to 50%. The corrosion test was performed in water at 60°C and in aqueous solutions of HCl and NaOH at room temperature, with mass losses measured after 15 days. The samples were pressed manually and heated at different temperatures: 110°C, 350°C and 500°C. The performed tests were transverse flexural strength, porosity and water absorption.
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Garfinkel-Shweky, D. y S. Yariv. "Metachromasy in clay dye systems: the adsorption of acridine orange by Na-beidellite". Clay Minerals 34, n.º 3 (septiembre de 1999): 459–67. http://dx.doi.org/10.1180/000985599546361.
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AbstractThe adsorption of the metachromic dye acridine orange (AO) by Na-beidellite was investigated by visible spectroscopy. Different types of clay-AO association were identified from the appearance and location of absorption bands α or β. The colloidal properties were determined from curves of the absorbance vs. the degree of saturation. Three regions were identified in the absorbance curve. In the first region beidellite is peptized with small amounts of AO and the dye penetrates into the interlayer space where it undergoes metachromasy due to π interactions between the aromatic entity and the oxygen plane of the clay. With larger amounts of AO (second region), the clay flocculates due to the aggregation of the dye cations in the interparticle space of the flocs. In excess AO (third region), beidellite is gradually peptized, forming small tactoids with monomeric AO in the interlayer space and at the same time adsorbing dimeric and polymeric AO cationic species at the solid-liquid interface. Compared with the other smectites, AO shows the greatest tendency to undergo metachromasy in the presence of beidellite.
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Aripin, H., S. Mitsudo, B. Rahmat, S. Tani, K. Sako, Y. Fujii, K. Kikuchi, T. Saito, T. Idehara y S. Sabchevski. "Formation of porous clay ceramic using sago waste ash as a prospective additive material with controllable milling". Science of Sintering 46, n.º 1 (2014): 55–64. http://dx.doi.org/10.2298/sos1401055a.
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A novel type of ceramic material was produced by mixing sago waste ash from the sago processing industry in Indonesia with clay. The composition was prepared by adding 50 %wt amount of sago waste into the clay, then a series of samples was milled for 6 h, 12 h, 24 h and 48 h, respectively. The samples were dry pressed and sintered at temperatures ranging from 800?C to 1200?C. The influence of the sintering temperature and the milling time on bulk density, firing shrinkage, water adsorption, and hardness was studied in detail. The results demonstrate that the low water absorption of less than 0.5% and the highest hardness of 5.82 GPa were obtained for the sample sintered at 1100?C and milled for 48 h. The investigation of the absorptive properties of such ceramics indicates that they could be recommended as a promising material for manufacturing of unglazed floor tiles.
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Chen, Hai Feng, Pei Song Tang, Min Hong Xu y Feng Cao. "Isotherms for Aqueous Potassium Adsorption and Characterization of Natural Pyrophyllite". Materials Science Forum 694 (julio de 2011): 682–85. http://dx.doi.org/10.4028/www.scientific.net/msf.694.682.
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The present investigatory founded an effectiveness of inexpensive and eco-friendly alumina silicate clay minerals, sericitic pyrophyllite (SP), as an adsorbent for the possible application in the absorption of K+. The crystal structure of pyrophyllite, size and morphology were characterized by XRD and SEM. In addition to pyrophyllite, quartz and were also contained in the minerals. The area of lamellar SP was about dozens um2. The results showed that potassium was absorbed on the SP under different pH and concentrations, and the best condition was pH=6, the time of equilibrium absorption = 30 min. It has been found that these natural minerals are effective in removing 55−75% of K+ from 5.0 to 20 mgL-1 KNO3 solutions. The applicability of the Langmuir, Freundlich and Dubinin-Radushkevich adsorption isotherms in each case of potassium was examined separately. We found that the adsorption process was endothermic in the case of SP and the Freundlich adsorption model was to more suitably represent the data. The work could provide the theoretical basis of the study of potassium ions adsorbed by pyrophyllite applying in fertilizer.
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Dick, Jeffrey C., Abdul Shakoor y Neil Wells. "A geological approach toward developing a mudrock-durability classification system". Canadian Geotechnical Journal 31, n.º 1 (1 de febrero de 1994): 17–27. http://dx.doi.org/10.1139/t94-003.
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Relationships between durability and lithologic characteristics of 61 mudrock samples from North America were investigated with the objective of developing a mudrock-durability classification based on lithologic characteristics. Second-cycle slake-durability index (Id2) was used as a measure of durability, whereas clay content, clay-mineral composition, texture, microfracture frequency, absorption, adsorption, dry density, void ratio, and Atterberg limits were used to characterize mudrock lithology. Based upon the amount of clay-size material, the presence or absence of laminations, and the degree of induration, the mudrocks were subdivided into claystones, mudstones, siltstones, shales, and argillites. The relationships between durability and lithologic characteristics were investigated separately for each class of mudrocks. The results show that different lithologic characteristics best correlate with the durability of each class of mudrocks. The durability of claystones correlates best with the amount of expandable clay minerals and that of mudstones with the frequency of microfractures. The degree of consolidation, as expressed by absorption, influences the durability of both siltstones and shales. The durability of argillites is related to their crystalline texture. Lithologic characteristics can be quantitatively related to a durability classification proposed herein that recognizes three classes of durability: low (Id2 < 50%), medium (Id2 = 50%–85%), and high (Id2 > 85%). Key words : mudrock, durability, lithologic characteristics, classification.
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Habold, Caroline, François Reichardt, Yvon Le Maho, Fabielle Angel, Nicole Liewig, Jean-Hervé Lignot y Hugues Oudart. "Clay ingestion enhances intestinal triacylglycerol hydrolysis and non-esterified fatty acid absorption". British Journal of Nutrition 102, n.º 2 (13 de enero de 2009): 249–57. http://dx.doi.org/10.1017/s0007114508190274.
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Consumption by animals and humans of earthy materials such as clay is often related to gut pathologies. Our aim was to determine the impact of kaolinite ingestion on glucose and NEFA transport through the intestinal mucosa. The expression of hexose transporters (Na/glucose co-transporter 1 (SGLT1), GLUT2, GLUT5) and of proteins involved in NEFA absorption (fatty acid transporter/cluster of differentiation 36 (FAT/CD36), fatty acid transport protein 4 (FATP4) and liver fatty acid binding protein (L-FABP)) was measured (1) in rats whose jejunum was perfused with a solution of kaolinite, and (2) in rats who ate spontaneously kaolinite pellets during 7 and 28 d. Also, we determined TAG and glucose absorption in the kaolinite-perfused group, and pancreatic lipase activity, gastric emptying and intestinal transit in rats orally administered with kaolinite. Glucose absorption was not affected by kaolinite perfusion or ingestion. However, kaolinite induced a significant increase in intestinal TAG hydrolysis and NEFA absorption. The cytoplasmic expression of L-FABP and FATP4 also increased due to kaolinite ingestion. NEFA may enter the enterocytes via endocytosis mainly since expression of NEFA transporters in the brush-border membrane was not affected by kaolinite. After uptake, rapid binding of NEFA by L-FABP and FATP4 could act as an intracellular NEFA buffer to prevent NEFA efflux. Increased TAG hydrolysis and NEFA absorption may be due to the adsorption properties of clay and also because kaolinite ingestion caused a slowing down of gastric emptying and intestinal transit.
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Ishak, Siti Nabihan y Nik Ahmad Nizam Nik Malek. "Functionalized layered double hydroxide with compound to remove cationic and anionic pollutants: A review". Environmental and Toxicology Management 1, n.º 1 (30 de abril de 2021): 26–29. http://dx.doi.org/10.33086/etm.v1i1.2062.
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Layered double hydroxide (LDH) is one of the promising clay minerals that show great potential in various applications owing to its versatile structural properties. Prominently known for its high anion exchange capacity, this allows LDH to be considered as one of the most effective adsorbents in removing anionic toxic. However, the structural property of LDH hinders it from removing cationic toxic. Therefore, LDH have been functionalized to enhance its adsorption properties. In the present work, we aim to summarize the recent progress of functionalized LDH with different compounds for removal of both anionic and cationic toxics. The adsorption isotherm and effect of pH on absorption capacity also have been briefly reviewed.
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Dzhigola, Lyudmila A. y Elizaveta A. Syutova. "Solid-phase concentration of calcium ions with mineral sorbents in creation of anti-icing materials". IZVESTIYA VYSSHIKH UCHEBNYKH ZAVEDENIY KHIMIYA KHIMICHESKAYA TEKHNOLOGIYA 61, n.º 9-10 (22 de octubre de 2018): 98–104. http://dx.doi.org/10.6060/ivkkt.20186109-10.5805a.
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The results of an experimental study of calcium ion adsorption processes carried out on various mineral sorbents of natural origin are presented. The sorption properties of the selected objects were studied and the possibility of their use as combined anti-icing materials was evaluated. In the work were investigated technological indicators of the quality of sorbents - the pH of the zero-charge point, the sorption capacity of sorbents and the optimum pH interval to determine the sorption activity of mineral raw materials on calcium ion. Analysis of the adsorption isotherms of calcium ions by the mineral sorbents studied makes it possible to note that the adsorption equilibrium on the clay is established more rapidly than on the opal of the marl type and marl. At the same time, the maximum absorption capacity of clay and marl has close values, which is related to the structure of the sorbent surface and the mineral composition of the materials. Opal of the marl type has a more developed surface, which is illustrated by a much higher absorption capacity and is confirmed by the values of the specific surface area. The obtained experimental data were processed using Freundlich, Langmuir, Temkin, and Dubinin-Radushkevich models. When describing the adsorption equilibrium of calcium ions on mineral sorbents, the Freyndlich isotherm is a more rigorous model, which indicates the presence of a large number of active centers and their exponential distribution on the surface of sorbents. The quantitative characteristics of the adsorption capacity of sorbents, found by adsorption models, made it possible to identify the optimum conditions of processes, establish a relationship between the values of the sorption of calcium ions by their structure and the porosity of the materials. It has been established that opal of marl type is the most effective carrier for producing anti-icing materials.
For citation:
Dzhigola L.A., Syutova E.A. Solid-phase concentration of calcium ions with mineral sorbents in creation of anti-icing materials. Izv. Vyssh. Uchebn. Zaved. Khim. Khim. Tekhnol. 2018. V. 61. N 9-10. P. 98-104
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Sharma, Priyanka y Kushal Qanungo. "Development of Mesoporous Geo-Adsorbent Pellets from Low Fire Clay and Cellulose for Removal of Methylene Blue in Aquaculture". Asian Journal of Chemistry 33, n.º 10 (2021): 2306–12. http://dx.doi.org/10.14233/ajchem.2021.23322.
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Porous ceramic pellets have been prepared using low fire clay and cellulose as a pore forming agent. The pore size and BET analysis, water absorption capacity and compressive strength of the pellets have been determined. The methylene blue uptake of pellets increased on increasing the percentage of initial cellulose content. Batch mode studies showed that the methylene blue adsorption decreased with increasing dose of pellets, increased with increasing initial dye concentration, while solution pH and presence of co-ions had negligible effect on removal of methylene blue, making them suitable for dye removal over a wide range of pH. The adsorption process followed both the Freundlich and Langmuir adsorption isotherms, whereas the adsorption kinetics followed the pseudo-second-order kinetic model. An inexpensive and simple device consisting of the mesoporous pellets enclosed in a tea ball wire mesh, which can be conveniently dipped and taken out of water in an aquarium and can remove methylene blue, has been developed.
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Tapia Estévez, M. J., F. López Arbeloa, T. López Arbeloa, I. López Arbeloa y R. A. Schoonheydt. "Spectroscopic Study of the Adsorption of Rhodamine 6G on Laponite B for Low Loadings". Clay Minerals 29, n.º 1 (marzo de 1994): 105–13. http://dx.doi.org/10.1180/claymin.1994.029.1.12.
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AbstractThe adsorption of Rhodamine 6G in aqueous suspension on Laponite B was investigated by electronic absorption and emission spectroscopies. Fluorescence spectra suggest that the monomer is adsorbed at two different surfaces, the external and the internal. A monomer is intercalated in the interlamellar space at low loading of dye (<3% CEC), whereas the monomeric state of the dye seems to be at the solid-aqueous interface in suspensions with high loading (>12% CEC). The metachromatic effect observed in the absorption spectra, for the loading interval between 1% and 15% CEC of Laponite B, is attributed to the dimerization of the dye, which seems, from X-ray diffraction measurements, to be formed at the clay interlayer. The formation constant and the absorption spectrum of the aggregate were obtained and the dimer was structurally characterized by applying the Exciton Theory. The observed fluorescence quenching for loadings lower than 15% CEC is attributed to energy transfer from monomer to the dimer, which obeys the Perrin model.
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Hatmoko, Dwi Rizaldi, Ari Handono Ramelan y Pranoto Pranoto. "Economic Impacts on The Use of Zeolite, Claystone, and Active Charcoal in Reducing Levels of Mercury (Hg) in Waste from Unlicensed Gold Mining Activities (PETI) in Kapuas Sub Watershed, Ulak Jaya Sintang Village". International Journal of Multicultural and Multireligious Understanding 6, n.º 5 (28 de noviembre de 2019): 919. http://dx.doi.org/10.18415/ijmmu.v6i5.1160.
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Research on the use of zeolite/clay/ activated charcoal composites as Hg heavy metal adsorbents has been carried out. Zeolites and clays were previously activated using NaOH, while activated charcoal was activated using HCl. The adsorbent characterization was carried out by Fourier Transform Infrared Analyzer (FTIR), X-Ray Diffraction (XRD), and mercury levels using Atomic Absorption Spectroscopy (AAS). Hg metal adsorption experiments were carried out by varying the composition of zeolite/claystone/ activated charcoal. The location of the study was Unlicensed Gold Mining (PETI) in the Kapuas watershed, Ulak Jaya Village, Sintang. The results showed that zeolite/claystone/ activated charcoal succeeded in reducing mercury levels in wastewater. The purpose of this study was to prove that the wastewater from gold mining could be reused to meet the needs of the community and improve environmental sustainability.
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Chen, Wanying, Zhihong Li, Bo Hao, Jianchuan Gao y Minqiang Fan. "A Machine Learning Based Intelligent Decision Support System for Flotation Dynamics in Simulation of Clay Minerals". Scientific Programming 2022 (23 de marzo de 2022): 1–11. http://dx.doi.org/10.1155/2022/7893940.
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In coal mines, process management is related with planning and flow of coal minerals from their mining points to journey’s end. The process is dependent on the operational decisions, which should be completed during coal production. In these systems, simulation modelling is assumed a powerful tool for decision making. The simulation modelling can further be enhanced through applying artificial intelligence (AI) and machine learning (ML) methods. The communication of water with clay minerals upholds the water adsorption on the clay surface, which makes them complex systems. Therefore, evading the water absorption from the clay turns out to be a hard job. The computational trainings of clay minerals are needed to comprehend the dynamics of water distribution. Tradition of coal slurry treatment is completed by adding medicament of its mineral flocculation sedimentation. As a result of coal, slime water contains a lot of clay minerals that are rich in kaolinite versatility and it is difficult to settle. The flotation will be one of the kaolinite recycling. In this paper, clay minerals containing a variety of minerals were taken as samples, and sodium dodecyl sulfate and sodium oleate were used as collectors to explore the flotation effect through test and molecular dynamics simulation. A machine learning based intelligent decision support system is designed to improve the outputs of the simulation model. The results show that when the pH value is 8 and the amount of collector and sec-octanol are 150 g/t and 250 g/t, respectively, the flotation rate of fine mineral can reach 63.25%. According to the molecular dynamics simulation results, the addition of the collector can reduce the hydrophilicity of the kaolinite surface, and the physical adsorption of SDS only occurs on the (001) surface.
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Chandler, Neil, John Palson y Todd Burns. "Capillary rise experiment to assess effectiveness of an enzyme soil stabilizer". Canadian Geotechnical Journal 54, n.º 10 (octubre de 2017): 1509–17. http://dx.doi.org/10.1139/cgj-2016-0511.
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An experimental program to assess of the attributes of an enzyme soil stabilizer is described. The focus of the program was two 1 year capillary rise experiments designed to test the influence of the soil additive on the soil’s adsorption of water. The enzyme additive is typically applied to marginal clay-based soils to improve the performance of road subgrades. The study investigated the potential increase in shear strength and the reduction in swelling. The two long-term soil column tests were conducted to measure water absorption due to capillary rise for soil specimens with, and without, enzyme treatment. The test results demonstrated that the addition of the enzyme soil additive had the effect of reducing water retained in the pore spaces of a partially saturated soil. The soil treated with the enzyme additive absorbed a lower quantity of water in the capillary rise test, and at a slower rate of absorption. The results from a concurrent suite of tests suggested that partially saturated clay having lower moisture content was linked to an increase in shear strength.
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Tang, Xiaodan, Hang Li, Hongyan Liu, Bing Li, Yuyan Zhao, Jilong Lu, Jian Zhou y Qingqing Liu. "Comparative Study on Two Pretreatment Processes for Chemical Phase Analysis of Gold in Geological Samples by Atomic Absorption Spectrometry". Journal of Analytical Methods in Chemistry 2019 (10 de julio de 2019): 1–8. http://dx.doi.org/10.1155/2019/1792792.
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Sample pretreatment is important for chemical phase analysis of elements. In this study, the geological samples of the Laozuoshan gold mine are chosen to pretreat by ultrasonic centrifugation and cyclotron oscillation, and the content of gold in eight chemical phases (water-soluble, ion exchange and clay adsorption, organic matter bound, iron-manganese oxide bound, naked or seminaked, carbonate bound, sulfide bound, and insoluble silicate states) is determined by atomic absorption spectrometry. The results show that the gold content of water-soluble, ion exchange and clay adsorption, iron-manganese oxide, and naked or seminaked states in the rock and ore samples is low, and some samples have high gold content of insoluble silicate states in the two methods. However, the gold content of organic matter bound, carbonate bound, and sulfide bound states obtained by ultrasonic centrifugation and cyclotron oscillation methods is significantly different. According to the X-ray fluorescence spectrometry data and the actual geological condition, the result given by the cyclotron oscillation method is more reasonable. The gold content of sulfide bound state in sediment samples is the highest and consistent with the mineral information, which could be applied to preliminarily predict the rock and ore conditions in the corresponding mining areas. In contrast with ultrasonic centrifugation, the cyclotron oscillation method has the advantages of simplicity, high efficiency, practicality, and environmental protection, and it can be better used for the determination of gold chemical phase state in geological samples by atomic absorption spectrometry.
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Gray-Wannell, Nia, Peter J. Holliman, H. Christopher Greenwell, Evelyne Delbos y Stephen Hillier. "Adsorption of phosphate by halloysite (7 Å) nanotubes (HNTs)". Clay Minerals 55, n.º 2 (junio de 2020): 184–93. http://dx.doi.org/10.1180/clm.2020.24.
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AbstractThe adsorption and retention of phosphates in soil systems is of wide environmental importance, and understanding the surface chemistry of halloysite (a common soil clay mineral) is also of prime importance in many emerging technological applications of halloysite nanotubes (HNTs). The adsorption of phosphate anions on tubular halloysite (7 Å) has been studied to gain a greater understanding of the mechanism and kinetics of adsorption on the surface of HNTs. Two well-characterized tubular halloysites with differing morphologies have been studied: one polygonal prismatic and one cylindrical, where the cylindrical form has a greater surface area and shorter tube length. Greater phosphate adsorption of up to 42 μmol g–1 is observed on the cylindrical halloysite when compared to the polygonal prismatic sample, where adsorption reached a maximum of just 15 μmol g–1 compared to a value for platy kaolinite (KGa-2) of 8 μmol g–1. Phosphate adsorption shows strong pH dependence, and the differences in phosphate sorption between the prismatic and cylindrical morphologies suggest that phosphate absorption does not occur at the same pH-dependent alumina edge sites and that the lumen may have a greater influence on uptake for the cylindrical form.
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Raduly, Monica Florentina, Valentin Raditoiu, Alina Raditoiu, Luminita Eugenia Wagner, Viorica Amariutei y Cristian Andi Nicolae. "Luminescent Hybrid Materials Based on Curcumin Derivatives Embedded in Palygorskite". Materiale Plastice 55, n.º 1 (30 de marzo de 2018): 63–67. http://dx.doi.org/10.37358/mp.18.1.4964.
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The seven curcumin derivatives were deposited on palygorskite in order to obtain hybrid materials. The fluorescence emission spectra of the obtained materials show a decrease in fluorescence intensity relative to the respective dyes, due to the environments around the dyestuff molecules created in the host matrices. Absorption studies show the best adsorption on the inorganic matrix, for the compounds with the hydroxyl groups. Correlating fluorescence spectra of hybrid materials with the results for absorption spectra of the dyes adsorbtion on the surface of the clay lead to the conclusion that a high percentage of the adsorbed dye had the effect of fluorescence quenching. Thus, it was confirmed that the fluorescent properties of hybrid materials depend on the interactions established between the fluorescent dyestuff and the inorganic network.
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Rejeb, Roua, Siegrid De Baere, Mathias Devreese, Richard Ducatelle, Siska Croubels, Madiha Hadj Ayed, Achraf Ghorbal y Gunther Antonissen. "Calcination Improves the In Vivo Efficacy of a Montmorillonite Clay to Bind Aflatoxin G1 in Broiler Chickens: A Toxicokinetic Approach". Toxins 12, n.º 10 (18 de octubre de 2020): 660. http://dx.doi.org/10.3390/toxins12100660.
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The goal of this study was to investigate the toxicokinetic characteristics of aflatoxin G1 (AFG1) in broiler chickens and the effect of calcination of a Tunisian montmorillonite clay on the in vivo absorption of AFG1. In this study, broiler chickens were randomly distributed into four groups of 10 animals. Group 1 was administered AFG1 (2 mg/kg body weight (BW)) by single intravenous injection (IV), group 2 received an intra-crop bolus (PO) of AFG1 without any clay, group 3 was dosed AFG1 PO together with an oral bolus of purified clay (CP), and group 4 received AFG1 PO with an oral bolus of calcined clay. A significant difference in the area under the curve (AUC0-t) was observed for group 4 (6.78 ± 4.24 h*ng/mL) in comparison with group 2 (12.83 ± 4.19 h*ng/mL). A significant reduction of the oral bioavailability of AFG1 was observed for group 4 (7.61 ± 4.76%) compared with group 2 (14.40 ± 4.70%), while no significant effect was observed of CP. In this experiment, no phase I nor phase II metabolites of AFG1 were observed. These findings confirm that calcination of the purified montmorillonite clay enhances the adsorption of AFG1 in the gastrointestinal tract after oral administration, thereby reducing its bioavailability, thus reducing its toxic effects.
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Mundim, Helen Sandra de Sousa Laet, Brunno Borges Canelhas, Fausto de Souza Pagan, Júlio Cesar de Sousa Inácio Gonçalves, Mário Sérgio da Luz y Deusmaque Carneiro Ferreira. "Optimization of Pb2+, Cd2+, Ni2+ and Ba2+ adsorption onto light expanded clay aggregate (LECA)". Ciência e Natura 44 (12 de abril de 2022): e3. http://dx.doi.org/10.5902/2179460x68809.
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The possibility of Pb2+, Cd2+, Ni2+ and Ba2+ ions removal from aqueous solution using light expanded clay aggregate (LECA) was investigated in this work. The central composite design (CCD) in response surface methodology (RSM) was used to optimize the operating parameters (adsorbent granulometry, absorption time and initial metal ions concentration) to reach the maximum ions removal in single and multi-elemental solutions. After optimization, the results shows that the removal efficiency decrease following the ion sequence Pb2+ > Ba2+ > Cd2+ > Ni2+ ions. The better efficiency (~95%) is observed for the Pb2+. The Langmuir and Freundlich isotherm models were applied to the equilibrium data at room temperature. The results revealed that data on LECA was very well fitted with Langmuir equations. The real interest of this work is to demonstrate that a simple material such as LECA can be used to remove extremely small levels of toxic metals, such as those found in drinking water. So our results could be the starting point for the development of a low-cost filtration system to remove toxic metals.
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Arai, Hirotsugu, Keizo Ishii, Shigeo Matsuyama, Fumito Fujishiro, Azusa Ishizaki, Naoyuki Osada, Hiroyuki Sugai et al. "Evaluating radiocesium retention ability of root-mat horizon using micro-PIXE analysis". International Journal of PIXE 24, n.º 01n02 (enero de 2014): 29–34. http://dx.doi.org/10.1142/s012908351450003x.
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A lot of radiocesium had been deposited onto pastures and grasslands following Fukushima Daiichi Nuclear Power Plant (FDNPP) accident. More radiocesium was accumulated in root-mat horizon than in both above ground plant bodies and mineral soils. In this study, factors causing higher radiocesium concentrations in root-mat horizon were evaluated by the addition of stable cesium solution and particle-induced X-ray emission (PIXE) analysis. Results suggest that adsorption onto root surfaces played a significant role in Cs accumulation in root-mat horizon. Furthermore, absorption of Cs was key to its long-term preservation. The adsorption of Cs by clay minerals also contributed to its retention. A slow water infiltration rate may also affect the enrichment of radiocesium in root-mat horizon. Based on these results, it is concluded that both biotic and abiotic factors contributed to the effective retention of radiocesium in root-mat horizons following the FDNPP accident.
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Honda, Mitsunori, Yui Kaneta y Tsuyoshi Yaita. "EXAFS investigation of strontium adsorption onto weathered biotite". AIP Advances 13, n.º 1 (1 de enero de 2023): 015314. http://dx.doi.org/10.1063/5.0106879.
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The efficiency of the sorption of Sr2+ on weathered biotite (WB), a type of clay mineral, was investigated. Removal of Sr2+ and Cs+ is important in the treatment of contaminated water from the 1F accident, which is one of the radionuclide waste treatment problems. We focused on developing an adsorption method for Sr ions using WB, which is abundant in Fukushima. Applying a molten salt treatment, the amount of sorbed Sr2+ simply increased as the added mass ratio of strontium chloride (SrCl2) increased from 1:1, 1:5, and 1:10 for the onefold, fivefold, and tenfold additions of SrCl2, respectively. Then, the crystal structure of WB as an adsorbent was evaluated by x-ray diffraction (XRD) analysis. Thus, it was observed that the WB retained its original crystal structure even after the sorption of Sr2+. Extended x-ray absorption fine structure (EXAFS) analysis was performed to investigate the local sorption structure of Sr2+ in the WB. The results revealed that Sr2+ was preferentially sorbed into the SiO4 and Al2O3 layers when Sr2+ was in the low mass ratio, whereas it was mainly sorbed into the SiO4 layer when the ratio was high.
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Nilpairach, Siriphan, Anucha Watchaikun, Kasidech Panyawatcharakom, Thanakorn Wasanapiarnpong y Noppasint Jiraborvornpongsa. "Effect of Aluminum Hydroxide Addition on Properties of Fired Refractory Clay Brick". Key Engineering Materials 766 (abril de 2018): 300–304. http://dx.doi.org/10.4028/www.scientific.net/kem.766.300.
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The pottery of Ratchaburi is very famous especially dragon jar which was fired by using dragon kiln. The kiln was made of unfired clay bricks, which its properties including high refractoriness, low thermal shrinkage and durable are desired. Aluminum hydroxide is an interesting material for improving brick’s properties, providing high active alumina (gamma-alumina) content after decomposition, high melting point and also reasonable cost. The study evaluated the effect of an additive, Al (OH)3, on the fried properties of refractory clay brick. In this study, four difference proportions of Al (OH)3 to clay , including 0:100, 25:75, 49:51 and 76:24 were studied. The specimens of 5x5x5 cm3 were formed by hand molding, then were fired at 1200, 1300 and 1400°C. The properties including refractoriness, volume shrinkage, strength, bulk density, water absorption, and slaking time were investigated. The samples of 25:75 ratio of Al (OH)3 to clay, which was fired at 1300°C exhibited high in refractoriness, low volume shrinkage of 5% and relatively low density of 1.69 g/cm3 as compared to those of 1400°C fired. Moreover, the moderate water adsorption of 15 % and useable compressive strength of 12.4 MPa was also observed. As a result, these properties suitable for using in firebox of dragon kiln of Ratchaburi province.
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Махмудова, Л. Ш., Х. Х. Ахмадова, Ж. Т. Хадисова, З. А. Абдулмежидова y Э. У. Идрисова. "INVESTIGATION OF EFFICIENCY OF NATURAL GAS DRYING BY ABSORPTION AND ADSORPTION METHODS". Вестник ГГНТУ. Технические науки, n.º 4(22) (25 de diciembre de 2020): 19–28. http://dx.doi.org/10.34708/gstou.2020.27.16.003.
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В статье проанализированы современные методы осушки природного газа для дальнейшей переработки его в метано-водородную смесь. Приведены результаты исследования абсорбционной и адсорбционной осушки природного газа жидкими реагентами (этиленгликолями) и твердыми адсорбентами (цеолитами и бентонитами). Показано, что природные бентонитовые глины обладают сравнительно небольшой адсорбционной активностью, их активация водными растворами Na2CО3 и H2SO4 способствует повышению адсорбционной активности, и их применение в комплексе с другими адсорбентами способствует значительному повышению процессов адсорбции. Авторами показана возможность и необходимость дальнейших исследований поиска эффективных методов активации бентонитовых глин. The article analyzes modern methods of drying natural gas for further processing it into a methane- hydrogen mixture. The results of studies of absorption and adsorption drying of natural gas with liquid reagents (ethylene glycols) and solid adsorbents (zeolites and bentonites) are presented. It is shown that natural bentonite clays have a relatively small adsorption activity, their activation with aqueous solutions of Na2CO3 and H2SO4 increases the adsorption activity, and their use in combination with other adsorbents contributes to a significant increase in the adsorption processes.The authors show the possibility and necessity of further research to find effective methods of activation of bentonite clays.
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Wang, Ning, Huihui Du, Qiaoyun Huang, Peng Cai, Xingmin Rong, Xionghan Feng y Wenli Chen. "Surface complexation modeling of Cd(II) sorption to montmorillonite, bacteria, and their composite". Biogeosciences 13, n.º 19 (6 de octubre de 2016): 5557–66. http://dx.doi.org/10.5194/bg-13-5557-2016.
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Abstract. Surface complexation modeling (SCM) has emerged as a powerful tool for simulating heavy metal adsorption processes on the surface of soil solid components under different geochemical conditions. The component additivity (CA) approach is one of the strategies that have been widely used in multicomponent systems. In this study, potentiometric titration, isothermal adsorption, zeta potential measurement, and extended X-ray absorption fine-structure (EXAFS) spectra analysis were conducted to investigate Cd adsorption on 2 : 1 clay mineral montmorillonite, on Gram-positive bacteria Bacillus subtilis, and their mineral–organic composite. We developed constant capacitance models of Cd adsorption on montmorillonite, bacterial cells, and mineral–organic composite. The adsorption behavior of Cd on the surface of the composite was well explained by CA-SCM. Some deviations were observed from the model simulations at pH < 5, where the values predicted by the model were lower than the experimental results. The Cd complexes of X2Cd, SOCd+, R-COOCd+, and R-POCd+ were the predominant species on the composite surface over the pH range of 3 to 8. The distribution ratio of the adsorbed Cd between montmorillonite and bacterial fractions in the composite as predicted by CA-SCM closely coincided with the estimated value of EXAFS at pH 6. The model could be useful for the prediction of heavy metal distribution at the interface of multicomponents and their risk evaluation in soils and associated environments.
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Adisu, Ngusey, Subramanian Balakrishnan y Haimanot Tibebe. "Synthesis and Characterization of Fe3O4-Bentonite Nanocomposite Adsorbent for Cr(VI) Removal from Water Solution". International Journal of Chemical Engineering 2022 (9 de septiembre de 2022): 1–18. http://dx.doi.org/10.1155/2022/4441718.
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Bentonite-magnetite nanocomposite adsorbent (BMNC) was made and investigated for its adsorption removal of Cr(VI) from an aqueous solution. This adsorbent was prepared by the coprecipitation method from sodium bentonite (BNa) with iron chloride solution at controlled pH and under an inert atmosphere. These adsorbents were characterized by atomic absorption spectrophotometer (AAS), Brunauer–Emmett–Teller (BET), dynamic light scattering (DLS), scanning electron microscope (SEM), Fourier transform infrared (FTIR) spectroscopy, and X-ray diffraction (XRD) analyses. Particle size of BMNC was in the range of 15 to 95 nm as per DLS. The intercalation of magnetite nanoparticles onto the bentonite clay increased its specific surface area from 142 to 177 m2/g as per BET analysis. Experimental design optimization results in 96.5% of Cr(VI) removal from the water solution at optimized adsorption parameters viz., adsorption time of 101 min, pH of 1.95, adsorbent dose of 1.12 g/L, and initial Cr(VI) concentration of 36.2 mg/L. The results of these studies demonstrate that the BMNC performs well. Moreover, the adsorption of Cr(VI) onto the BMNC was found to be the best fit with Langmuir isotherm (R2 = 0.9984) and a maximum adsorption capacity of 98 mg/g. The kinetics of the adsorption process was found to be a pseudo-second-order model (R2 = 0.9912). The BMNC also showed favourable reusability for adsorbate Cr(VI) ions removal from the water solution.
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Zhang, Xiao, Chen Chen, Ting Cheng, Mingyue Wen, Lei Wang y Fenxu Pan. "Making Pb Adsorption-Saturated Attapulgite with Excellent Photocatalysis Properties through a Vulcanization Reaction and Its Application for MB Wastewater Degradation". International Journal of Environmental Research and Public Health 19, n.º 16 (22 de agosto de 2022): 10457. http://dx.doi.org/10.3390/ijerph191610457.
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Attapulgite (AT) is a clay mineral with rich reserves in China, and it has good adsorption activity for Pb-containing wastewater. However, as a hazardous waste, the treatment of Pb adsorption-saturated attapulgite was quite difficult. In this work, through a simple vulcanization reaction, the waste Pb adsorption-saturated attapulgite (AT@Pb) was transformed into composite materials (AT@PbS) with good photocatalytic performance. After comprehensive material characterization (including XRD, TEM, XPS, and UV-Vis), the photocatalytic degradation performance and mechanism of AT@PbS for methylene blue (MB) were investigated. The results revealed that AT@PbS was a composite material of attapulgite nanorods (500–600 nm) and nanosquare PbS particles (80–100 nm). Additionally, AT@PbS displayed good visible light absorption, improved photo-electric properties, excellent photodegradation performance for MB, and recycling stability. Moreover, the energy band range of AT@PbS was about −0.043 V to 1.367 V. The photo-generated holes and their derived hydroxyl radicals were the main active species for MB degradation. This work not only provides a new approach to construct the composite photocatalyst, but also demonstrates the possibility of the comprehensive utilization of heavy metal adsorbents for wastewater degradation.
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Baghaie, Amir Hossein y Mehran Keshavarzi. "The Effect of Montmorillonite Nano-Clay on the Changes in Petroleum Hydrocarbon Degradation and Cd Concentration in Plants Grown in Cd-Polluted Soil". Avicenna Journal of Environmental Health Engineering 5, n.º 2 (29 de diciembre de 2018): 100–105. http://dx.doi.org/10.15171/ajehe.2018.13.
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Contamination with heavy metals and petroleum hydrocarbons is considered as an environmental problem. Thus, this research was done to evaluate the effect of montmorillonite nano-clay on the changes in petroleum hydrocarbon degradation and cadmium (Cd) concentration in plant grown in a Cd-polluted soil. Treatments consisted of two levels of montmorillonite nano-clay (0 and 1% W/W) in a Cd-polluted soil (0, 5, 10 mg Cd/kg soil) and crude oil-polluted soil (0, 1 and 2% W/W). The plant used in this study was Tall Fescue (Festuca arundinacea L.). After 20 weeks, the concentration of Cd in plants was measured by atomic absorption spectroscopy and the total petroleum hydrocarbon (TPHs) in the soil was determined using the GC-mass spectrometry. Soil respiration was determined according to the method used by Qiao et al. ANOVA was used for statistical analysis of data. The least significant difference (LSD) test was used to determine the differences between the means. The application of 1% (w/w) montmorillonite nano-clay in Cd-polluted soil (10 mg Cd) without crude oil decreased Cd concentration in plant and increased microbial respiration by 18% and 34%, respectively. In addition, the application of 1% montmorillonite nano-clay in soil polluted with 1% crude oil and 10 mg Cd enhanced TPHs degradation by 27%. The use of montmorillonite nano-clay increased Cd adsorption in soil which resulted in an increase in microbial respiration and, hence the degradability of petroleum hydrocarbon in the soil.