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Organo-Clays As Sorbents of Hydrophobic Organic Contaminants: Sorptive Characteristics and Approaches to Enhancing Sorption Capacity

Published online by Cambridge University Press:  01 January 2024

Runliang Zhu ,
Qing Zhou ,
Jianxi Zhu ,
Yunfei Xi  and
Hongping He
Runliang Zhu
Affiliation:
Key Laboratory of Mineralogy and Metallogeny, Guangzhou Institute of Geochemistry, Chinese Academy of Sciences, 510640, Guangzhou, China
Qing Zhou
Affiliation:
Key Laboratory of Mineralogy and Metallogeny, Guangzhou Institute of Geochemistry, Chinese Academy of Sciences, 510640, Guangzhou, China
Jianxi Zhu
Affiliation:
Key Laboratory of Mineralogy and Metallogeny, Guangzhou Institute of Geochemistry, Chinese Academy of Sciences, 510640, Guangzhou, China
Yunfei Xi
Affiliation:
Nanotechnology and Molecular Science Discipline, Faculty of Science and Engineering, Queensland University of Technology, 2 George Street, Brisbane, QLD 4000, Australia
Hongping He*
Affiliation:
Key Laboratory of Mineralogy and Metallogeny, Guangzhou Institute of Geochemistry, Chinese Academy of Sciences, 510640, Guangzhou, China
*
* E-mail address of corresponding author: hehp@gig.ac.cn
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Abstract

When clay minerals, notably smectites, intercalate organic cations, their interlayer surfaces change from hydrophilic to hydrophobic. The resultant intercalates, known as organo-clays (OCs), have a large affinity for hydrophobic organic contaminants (HOCs). Organo-clays are used as sorbents of HOCs in wastewater treatment and as sorptive barriers in landfill liners. The structural and sorptive characteristics of OCs with respect to HOCs have been studied extensively, and a large volume of literature has accumulated over the past few decades. The interactions of OCs with HOCs and the various approaches to improving the sorption capacity of OCs are reviewed here, with particular reference to the application of novel analytical techniques, such as molecular modeling, to characterizing the OC—HOC interaction.

Keywords

Hydrophobic Organic ContaminantsOrgano-claysSorptionEnvironmental RemediationInterlayer Space
Type
Research Article
Information
Clays and Clay Minerals , Volume 63 , Issue 3 , June 2015 , pp. 199 - 221
Copyright
Copyright © Clay Minerals Society 2015

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