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RSM optimization studies for cadmium ions adsorption onto pristine and acid-modified kaolinite clay

Clay has been reported as an active absorbent for the removal of toxic heavy metals from aqueous medium. In this study, pristine and acid modified kaolinite clays (PKC and AMKC) were prepared, characterized using various analyses, and tested for Cd(2+) ion adsorption from textile industry wastewater...

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Detalles Bibliográficos
Autores principales: Mustapha, L.S., Yusuff, A.S., Dim, P.E.
Formato: Online Artículo Texto
Lenguaje:English
Publicado: Elsevier 2023
Materias:
Acceso en línea:https://www.ncbi.nlm.nih.gov/pmc/articles/PMC10404677/
https://www.ncbi.nlm.nih.gov/pubmed/37554808
http://dx.doi.org/10.1016/j.heliyon.2023.e18634
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author Mustapha, L.S.
Yusuff, A.S.
Dim, P.E.
author_facet Mustapha, L.S.
Yusuff, A.S.
Dim, P.E.
author_sort Mustapha, L.S.
collection PubMed
description Clay has been reported as an active absorbent for the removal of toxic heavy metals from aqueous medium. In this study, pristine and acid modified kaolinite clays (PKC and AMKC) were prepared, characterized using various analyses, and tested for Cd(2+) ion adsorption from textile industry wastewater. After acid modification, the specific surface area of clay increased from 84.2 to 389.4 m(2)/g. Adsorption isotherm, kinetics and thermodynamics behaviour process were examined. The pH at (pH(pzc)) of 8.5 indicate that AMKC surface is positively charged for pH below the pH(pzc) attracting anions. Response surface methodology was used to investigate the effect of adsorption process factors on Cd(2+) ion removal uptake. At the optimum process conditions of 45.3 °C temperature, 0.63 g/L adsorbent dosage, and 120.9 min contact time, the percentages of Cd(2+) adsorbed by PKC and AMKC were 77.82% and 99.19%, respectively. Various models were employed to analyzed the kinetic and equilibrium data. The Pseudo-first order, Pseudo-second order and Intra-particle diffusion were used to evaluate the kinetic data, while the Langmuir, Freundlich and Temkin isotherm models were applied to analyzed the equilibrium data. The sorption kinetics was found to be best described by Pseudo-second order considering the high correlation coefficient (R(2)), smaller Chi-square (ᵪ2) and sum of square error (SSE). The Freundlich model was the most accurate in describing the equilibrium data followed by Langmuir and Temkin respectively. The thermodynamic reveal that the reaction is spontaneous and endothermic in nature, and increase in randomness between the adsorbent and adsorbate. The obtained activation energy (Ea) value suggest that the adsorption mechanism of Cd(II) is a physisorption dominated.
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spelling pubmed-104046772023-08-08 RSM optimization studies for cadmium ions adsorption onto pristine and acid-modified kaolinite clay Mustapha, L.S. Yusuff, A.S. Dim, P.E. Heliyon Research Article Clay has been reported as an active absorbent for the removal of toxic heavy metals from aqueous medium. In this study, pristine and acid modified kaolinite clays (PKC and AMKC) were prepared, characterized using various analyses, and tested for Cd(2+) ion adsorption from textile industry wastewater. After acid modification, the specific surface area of clay increased from 84.2 to 389.4 m(2)/g. Adsorption isotherm, kinetics and thermodynamics behaviour process were examined. The pH at (pH(pzc)) of 8.5 indicate that AMKC surface is positively charged for pH below the pH(pzc) attracting anions. Response surface methodology was used to investigate the effect of adsorption process factors on Cd(2+) ion removal uptake. At the optimum process conditions of 45.3 °C temperature, 0.63 g/L adsorbent dosage, and 120.9 min contact time, the percentages of Cd(2+) adsorbed by PKC and AMKC were 77.82% and 99.19%, respectively. Various models were employed to analyzed the kinetic and equilibrium data. The Pseudo-first order, Pseudo-second order and Intra-particle diffusion were used to evaluate the kinetic data, while the Langmuir, Freundlich and Temkin isotherm models were applied to analyzed the equilibrium data. The sorption kinetics was found to be best described by Pseudo-second order considering the high correlation coefficient (R(2)), smaller Chi-square (ᵪ2) and sum of square error (SSE). The Freundlich model was the most accurate in describing the equilibrium data followed by Langmuir and Temkin respectively. The thermodynamic reveal that the reaction is spontaneous and endothermic in nature, and increase in randomness between the adsorbent and adsorbate. The obtained activation energy (Ea) value suggest that the adsorption mechanism of Cd(II) is a physisorption dominated. Elsevier 2023-07-27 /pmc/articles/PMC10404677/ /pubmed/37554808 http://dx.doi.org/10.1016/j.heliyon.2023.e18634 Text en © 2023 The Authors. Published by Elsevier Ltd. https://creativecommons.org/licenses/by-nc-nd/4.0/This is an open access article under the CC BY-NC-ND license (http://creativecommons.org/licenses/by-nc-nd/4.0/).
spellingShingle Research Article
Mustapha, L.S.
Yusuff, A.S.
Dim, P.E.
RSM optimization studies for cadmium ions adsorption onto pristine and acid-modified kaolinite clay
title RSM optimization studies for cadmium ions adsorption onto pristine and acid-modified kaolinite clay
title_full RSM optimization studies for cadmium ions adsorption onto pristine and acid-modified kaolinite clay
title_fullStr RSM optimization studies for cadmium ions adsorption onto pristine and acid-modified kaolinite clay
title_full_unstemmed RSM optimization studies for cadmium ions adsorption onto pristine and acid-modified kaolinite clay
title_short RSM optimization studies for cadmium ions adsorption onto pristine and acid-modified kaolinite clay
title_sort rsm optimization studies for cadmium ions adsorption onto pristine and acid-modified kaolinite clay
topic Research Article
url https://www.ncbi.nlm.nih.gov/pmc/articles/PMC10404677/
https://www.ncbi.nlm.nih.gov/pubmed/37554808
http://dx.doi.org/10.1016/j.heliyon.2023.e18634
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