中国科学院重庆绿色智能技术研究院机构知识库

In order to enhance sorption capacity of palygorskite for heavy metals, mercapto functionalized palygorskite (MPAL) were prepared and utilized for the sorption of Cu2+ from aqueous solution. Sorption kinetic and thermodynamic experiments were conducted to assess the sorption behavior and application potentials for the remediation of heavy-meta-polluted soil. Sorption mechanisms were investigated by XRD, FT-IR, Si-29 CP/MAS NMR, SEM-EDS and XPS in detail. The maximum sorption amount of Cu2+ on MPAL was approximately 30 mg/g, which was 10 times more than pristine palygorskite. Freundlich isotherm describes the sorption data better than other isotherms, and pseudo second order kinetic model fit the sorption kinetic processes well. The positive enthalpy change confirmed that the sorption process of MPAL was endothermic and the positive entropy changes revealed that sorption of Cu2+ was driven by entropy changes. Further characterization analyses and the "Hard and Soft Acids and Bases theory" for mechenism research exhibited the complexation existence of Cu2+ with mercapto groups. The good performance demonstrated that MPAL has great potential application values in removal of heavy metals both from aqueous and soils. (C) 2014 The Korean Society of Industrial and Engineering Chemistry. Published by Elsevier B.V. All rights reserved.