Cargando…
Adsorption of Cd(2+) onto apatite surface: Equilibrium, kinetics and thermodynamic studies
This study examined the application of chemically synthesized apatite (CHAp) powder as a potential adsorbent for the elimination of Cd(2+) in aqueous medium. The synthesized hydroxyapatite (HAp) powder before and after adsorption was elucidated by XRD, EDX, FT-IR, SEM, and TEM analytical techniques....
Autores principales: | , , , |
---|---|
Formato: | Online Artículo Texto |
Lenguaje: | English |
Publicado: |
Elsevier
2023
|
Materias: | |
Acceso en línea: | https://www.ncbi.nlm.nih.gov/pmc/articles/PMC9898600/ https://www.ncbi.nlm.nih.gov/pubmed/36747536 http://dx.doi.org/10.1016/j.heliyon.2023.e12971 |
_version_ | 1784882460240117760 |
---|---|
author | Andrew Ofudje, Edwin Sodiya, Ezekiel F. Olanrele, Olajire S. Akinwunmi, Fatai |
author_facet | Andrew Ofudje, Edwin Sodiya, Ezekiel F. Olanrele, Olajire S. Akinwunmi, Fatai |
author_sort | Andrew Ofudje, Edwin |
collection | PubMed |
description | This study examined the application of chemically synthesized apatite (CHAp) powder as a potential adsorbent for the elimination of Cd(2+) in aqueous medium. The synthesized hydroxyapatite (HAp) powder before and after adsorption was elucidated by XRD, EDX, FT-IR, SEM, and TEM analytical techniques. The role of time, initial Cd(2+) concentration, amount of CHAp used, temperature and solution pH on the adsorption process were investigated. Data from the adsorption process were subjected to Dubinin-Radushkevich, Langmuir, Freundlich, and Tempkin adsorption isotherms, while pseudo-first-order, pseudo-second-order, Elovich and intraparticle diffusion kinetic models were used for the kinetics investigation. Results from XRD confirmed that chief characteristic peaks of HAp powder were detected, while functional groups such as PO(4)(3−), CO(3)(2−) and OH(−) matching pure HAp were displayed in the FT-IR spectra. Round shape morphology of the CHAp was confirmed by SEM and TEM analyses. Langmuir isotherm best described the adsorption process with ceiling adsorption capacity of 195.711 mg/g, whereas, the adsorption mechanism obeys the pseudo-first-order model which suggests a physical adsorption process. The value of entropy change (ΔS) of the adsorption of Cd(2+) onto CHAp surface was obtained to be 0.610 kJ/mol, while the value of enthalpy change obtained was 175.591 kJ/mol. Results from free energy change obtained adjudged the adsorption process to be spontaneous and endothermic in character. Thus, the chemically synthesized HAp could be an excellent adsorbent for the elimination of Cd(2+) in bioremediation applications. |
format | Online Article Text |
id | pubmed-9898600 |
institution | National Center for Biotechnology Information |
language | English |
publishDate | 2023 |
publisher | Elsevier |
record_format | MEDLINE/PubMed |
spelling | pubmed-98986002023-02-05 Adsorption of Cd(2+) onto apatite surface: Equilibrium, kinetics and thermodynamic studies Andrew Ofudje, Edwin Sodiya, Ezekiel F. Olanrele, Olajire S. Akinwunmi, Fatai Heliyon Research Article This study examined the application of chemically synthesized apatite (CHAp) powder as a potential adsorbent for the elimination of Cd(2+) in aqueous medium. The synthesized hydroxyapatite (HAp) powder before and after adsorption was elucidated by XRD, EDX, FT-IR, SEM, and TEM analytical techniques. The role of time, initial Cd(2+) concentration, amount of CHAp used, temperature and solution pH on the adsorption process were investigated. Data from the adsorption process were subjected to Dubinin-Radushkevich, Langmuir, Freundlich, and Tempkin adsorption isotherms, while pseudo-first-order, pseudo-second-order, Elovich and intraparticle diffusion kinetic models were used for the kinetics investigation. Results from XRD confirmed that chief characteristic peaks of HAp powder were detected, while functional groups such as PO(4)(3−), CO(3)(2−) and OH(−) matching pure HAp were displayed in the FT-IR spectra. Round shape morphology of the CHAp was confirmed by SEM and TEM analyses. Langmuir isotherm best described the adsorption process with ceiling adsorption capacity of 195.711 mg/g, whereas, the adsorption mechanism obeys the pseudo-first-order model which suggests a physical adsorption process. The value of entropy change (ΔS) of the adsorption of Cd(2+) onto CHAp surface was obtained to be 0.610 kJ/mol, while the value of enthalpy change obtained was 175.591 kJ/mol. Results from free energy change obtained adjudged the adsorption process to be spontaneous and endothermic in character. Thus, the chemically synthesized HAp could be an excellent adsorbent for the elimination of Cd(2+) in bioremediation applications. Elsevier 2023-01-12 /pmc/articles/PMC9898600/ /pubmed/36747536 http://dx.doi.org/10.1016/j.heliyon.2023.e12971 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 Andrew Ofudje, Edwin Sodiya, Ezekiel F. Olanrele, Olajire S. Akinwunmi, Fatai Adsorption of Cd(2+) onto apatite surface: Equilibrium, kinetics and thermodynamic studies |
title | Adsorption of Cd(2+) onto apatite surface: Equilibrium, kinetics and thermodynamic studies |
title_full | Adsorption of Cd(2+) onto apatite surface: Equilibrium, kinetics and thermodynamic studies |
title_fullStr | Adsorption of Cd(2+) onto apatite surface: Equilibrium, kinetics and thermodynamic studies |
title_full_unstemmed | Adsorption of Cd(2+) onto apatite surface: Equilibrium, kinetics and thermodynamic studies |
title_short | Adsorption of Cd(2+) onto apatite surface: Equilibrium, kinetics and thermodynamic studies |
title_sort | adsorption of cd(2+) onto apatite surface: equilibrium, kinetics and thermodynamic studies |
topic | Research Article |
url | https://www.ncbi.nlm.nih.gov/pmc/articles/PMC9898600/ https://www.ncbi.nlm.nih.gov/pubmed/36747536 http://dx.doi.org/10.1016/j.heliyon.2023.e12971 |
work_keys_str_mv | AT andrewofudjeedwin adsorptionofcd2ontoapatitesurfaceequilibriumkineticsandthermodynamicstudies AT sodiyaezekielf adsorptionofcd2ontoapatitesurfaceequilibriumkineticsandthermodynamicstudies AT olanreleolajires adsorptionofcd2ontoapatitesurfaceequilibriumkineticsandthermodynamicstudies AT akinwunmifatai adsorptionofcd2ontoapatitesurfaceequilibriumkineticsandthermodynamicstudies |