Enhanced adsorptive removal of Cr(VI)in aqueous solution by polyethyleneimine modified palygorskite  

作　　者：Jiahong Wang Tongtong Sun Atif Saleem Yao Chen 

机构地区：[1]School of Environmental Science and Engineering,Shaanxi University of Science and Technology,Xi'an 710021,China [2]Shaanxi Key Laboratory of Green Preparation and Functionalization of Inorganic Materials,Xi'an 710021,China

出　　处：《Chinese Journal of Chemical Engineering》2020年第10期2650-2657,共8页中国化学工程学报（英文版）

基　　金：funded by the National Natural Science Foundation of China(21677092);the Scientific Research Program funded by Shaanxi Provincial Education Department(15JK1095)。

摘　　要：Polyethyleneimine(PEI)modified palygorskite(Pal)was used for the adsorption of Cr(VI)in aqueous solution.The absorbent was characterized by Fourier transform infrared spectroscopy(FT-IR)and thermogravimetric analysis(TGA).Characterized results confirmed that the Pal has been successfully modified by PEI.The modification of PEI increased the Cr(VI)adsorption performance of the Pal by the adsorption combined reduction mechanism,and amino groups of the adsorbent play the main role in the enhanced Cr(VI)adsorption.The maximum adsorption capacity was 51.10 mg·g^-1 at pH4.0 and 25°C.The adsorption kinetics of Cr(VI)on the adsorbent conforms to the Langmuir isotherm model.The maximum adsorption occurs at pH3,and then the adsorption capacity of PEI-Pal was decreased with the increase of p H values.The adsorption kinetics of Cr(VI)on PEI-Pal was modeled with pseudo-second-order model.The addition of Cl^-,SO4^2-and PO4^3-reduced the Cr(VI)adsorption by competition with Cr(VI)for the active sites of PEI-Pal.The Cr(VI)saturated PEI-Pal can be regenerated in alkaline solution,and the adsorption capacity can still be maintained at 30.44 mg·g^-1 after 4 cycles.The results demonstrate that PEI-Pal can be used as a potential adsorbent of Cr(VI)in aqueous solutions.

关 键 词：PALYGORSKITE POLYETHYLENEIMINE ADSORPTION CR(VI) 

分 类 号：TQ424[化学工程] X703[环境科学与工程—环境工程]