Adsorption of Cr(VI) on the MWCNTs/attapulgite composites
WANG Cai-yun1, LIU Lian2, LI Chuang1, JIANG Ting-ting1, CHEN Wei-jia1, WANG Li-hong1, ZHANG Xiao-liang1
1. Jiangxi Inorganic Membrane Materials Engineering Research Center, College of Chemistry and Chemical Engineering, Jiangxi Normal University, Nanchang 330022, China;
2. Hydrology Bureau of Jiangxi Province, Nanchang 330002, China
As a kind of cheap natural clay, the attapulgite (APT) was modified by carboxyl multi-walled carbon nanotubes (MWCNTs). The MWCNTs/attapulgite composites were characterized by XRD, FT-IR and FE-SEM. The results indicated that the MWCNTs/APT composites were successfully synthesized by the modification reaction with MWCNTs on APT. The isothermal adsorption experiments of Cr(VI) on the MWCNTs/APT composites showed that the maximum adsorption capacity was obtained over 14.9mg/g under pH of 2 and adsorption time for 12h at 293.15K. The adsorption of Cr(VI) on the MWCNTs/APT composites followed a pseudo-first-order kinetic model and the experimental data were best fitted the Langmuir isotherm model. The negative values of ΔGo and the positive values of ΔHo and ΔSo indicated that it was spontaneous, endothermic and entropy-increasing nature of this adsorption process. Compared with pure APT clay and carboxyl MWCNTs, such MWCNTs/APT composites could effectively improve the adsorption performance for Cr(VI), and would have a good application prospect in the wastewater treatment containing chromium.
王彩云, 刘恋, 李创, 江婷婷, 陈伟佳, 王丽红, 张小亮. MWCNTs改性凹凸棒土对水中Cr (VI)的吸附研究[J]. 中国环境科学, 2017, 37(6): 2179-2186.
WANG Cai-yun, LIU Lian, LI Chuang, JIANG Ting-ting, CHEN Wei-jia, WANG Li-hong, ZHANG Xiao-liang. Adsorption of Cr(VI) on the MWCNTs/attapulgite composites. CHINA ENVIRONMENTAL SCIENCECE, 2017, 37(6): 2179-2186.
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