Removal of Lead and Cadmium Ions from Aqueous Solution by Polyvinyl Alcohol-Modified Kaolinite Clay: A Novel Nano-Clay Adsorbent

Kaolinite clay was modified with polyvinyl alcohol (PVA) to obtain a PVA–nano-clay adsorbent. X-Ray diffraction measurements of the adsorbent showed no observable change in the d-spacing of its crystal lattice. Scanning electron microscopy of the PVA-modified nano-clay adsorbent indicated the presen...

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Main Authors: E.I. Unuabonah, B.I. Olu-Owolabi, K.O. Adebowale, L.Z. Yang
Format: Article
Language:English
Published: SAGE Publishing 2008-07-01
Series:Adsorption Science & Technology
Online Access:https://doi.org/10.1260/0263-6174.26.6.383
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author E.I. Unuabonah
B.I. Olu-Owolabi
K.O. Adebowale
L.Z. Yang
author_facet E.I. Unuabonah
B.I. Olu-Owolabi
K.O. Adebowale
L.Z. Yang
author_sort E.I. Unuabonah
collection DOAJ
description Kaolinite clay was modified with polyvinyl alcohol (PVA) to obtain a PVA–nano-clay adsorbent. X-Ray diffraction measurements of the adsorbent showed no observable change in the d-spacing of its crystal lattice. Scanning electron microscopy of the PVA-modified nano-clay adsorbent indicated the presence of irregular crystal structures. Infrared spectroscopy suggested that the PVA–nano-clay adsorbent basically possessed outer –OH functional groups. This adsorbent was found to have an adsorption capacity of 56.18 mg/g for Pb 2+ ions and 41.67 mg/g for Cd 2+ ions. The adsorption data obtained was well explained by the Diffuse Layer Model (DLM), which implies that the adsorption of both metal ions onto the modified adsorbent was via an inner-sphere surface complexation mechanism. The ΔH 0 values for the adsorption of both metal ions onto the PVA–nano-clay were −12.48 kJ/mol for Pb 2+ ions and −13.49 kJ/mol for Cd 2+ ions, with both ions exhibiting negative adsorption entropies. Data-fitting indicated that both the PVA–nano-clay and the unmodified adsorbent possessed homogeneous and heterogeneous adsorption sites. Virtually complete desorption (ca. 99%) of both metal ions occurred from PVA–nano-clay within 3 min.
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institution Kabale University
issn 0263-6174
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language English
publishDate 2008-07-01
publisher SAGE Publishing
record_format Article
series Adsorption Science & Technology
spelling doaj-art-7066fd8520a54a9f8e0c1d8f202dc5012025-01-02T02:57:59ZengSAGE PublishingAdsorption Science & Technology0263-61742048-40382008-07-012610.1260/0263-6174.26.6.383Removal of Lead and Cadmium Ions from Aqueous Solution by Polyvinyl Alcohol-Modified Kaolinite Clay: A Novel Nano-Clay AdsorbentE.I. Unuabonah0B.I. Olu-Owolabi1K.O. Adebowale2L.Z. Yang Department of Pure and Industrial Chemistry, College of Sciences, Federal University of Petroleum Resources, PMB 1221, Effurun, Nigeria Department of Chemistry, Faculty of Science, University of Ibadan, Nigeria. (3) Institute of Soil Science, Nanjing, Jiangsu Province, P. R. China Department of Chemistry, Faculty of Science, University of Ibadan, Nigeria. (3) Institute of Soil Science, Nanjing, Jiangsu Province, P. R. ChinaKaolinite clay was modified with polyvinyl alcohol (PVA) to obtain a PVA–nano-clay adsorbent. X-Ray diffraction measurements of the adsorbent showed no observable change in the d-spacing of its crystal lattice. Scanning electron microscopy of the PVA-modified nano-clay adsorbent indicated the presence of irregular crystal structures. Infrared spectroscopy suggested that the PVA–nano-clay adsorbent basically possessed outer –OH functional groups. This adsorbent was found to have an adsorption capacity of 56.18 mg/g for Pb 2+ ions and 41.67 mg/g for Cd 2+ ions. The adsorption data obtained was well explained by the Diffuse Layer Model (DLM), which implies that the adsorption of both metal ions onto the modified adsorbent was via an inner-sphere surface complexation mechanism. The ΔH 0 values for the adsorption of both metal ions onto the PVA–nano-clay were −12.48 kJ/mol for Pb 2+ ions and −13.49 kJ/mol for Cd 2+ ions, with both ions exhibiting negative adsorption entropies. Data-fitting indicated that both the PVA–nano-clay and the unmodified adsorbent possessed homogeneous and heterogeneous adsorption sites. Virtually complete desorption (ca. 99%) of both metal ions occurred from PVA–nano-clay within 3 min.https://doi.org/10.1260/0263-6174.26.6.383
spellingShingle E.I. Unuabonah
B.I. Olu-Owolabi
K.O. Adebowale
L.Z. Yang
Removal of Lead and Cadmium Ions from Aqueous Solution by Polyvinyl Alcohol-Modified Kaolinite Clay: A Novel Nano-Clay Adsorbent
Adsorption Science & Technology
title Removal of Lead and Cadmium Ions from Aqueous Solution by Polyvinyl Alcohol-Modified Kaolinite Clay: A Novel Nano-Clay Adsorbent
title_full Removal of Lead and Cadmium Ions from Aqueous Solution by Polyvinyl Alcohol-Modified Kaolinite Clay: A Novel Nano-Clay Adsorbent
title_fullStr Removal of Lead and Cadmium Ions from Aqueous Solution by Polyvinyl Alcohol-Modified Kaolinite Clay: A Novel Nano-Clay Adsorbent
title_full_unstemmed Removal of Lead and Cadmium Ions from Aqueous Solution by Polyvinyl Alcohol-Modified Kaolinite Clay: A Novel Nano-Clay Adsorbent
title_short Removal of Lead and Cadmium Ions from Aqueous Solution by Polyvinyl Alcohol-Modified Kaolinite Clay: A Novel Nano-Clay Adsorbent
title_sort removal of lead and cadmium ions from aqueous solution by polyvinyl alcohol modified kaolinite clay a novel nano clay adsorbent
url https://doi.org/10.1260/0263-6174.26.6.383
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