Modification of 13X Molecular Sieve by Chitosan for Adsorptive Removal of Cadmium from Simulated Wastewater

Yan Shi; Ken Sun; Lixin Huo; Xiuxiu Li; Xuebin Qi; Zhaohui Li

doi:10.3390/ma10091101

Modification of 13X Molecular Sieve by Chitosan for Adsorptive Removal of Cadmium from Simulated Wastewater

Materials (Basel). 2017 Sep 19;10(9):1101. doi: 10.3390/ma10091101.

Authors

Yan Shi¹, Ken Sun², Lixin Huo³, Xiuxiu Li⁴, Xuebin Qi⁵, Zhaohui Li⁶

Affiliations

¹ School of Environmental and Municipal Engineering, North China University of Water Resources and Electric Power, Zhengzhou 450045, China. shiyan@ncwu.edu.cn.
² School of Environmental and Municipal Engineering, North China University of Water Resources and Electric Power, Zhengzhou 450045, China. sunken@ncwu.edu.cn.
³ School of Environmental and Municipal Engineering, North China University of Water Resources and Electric Power, Zhengzhou 450045, China. 18748975624@163.com.
⁴ Henan Province key Laboratory of Water-Saving Agriculture, North China University of Water Resources and Electric Power, Zhengzhou 450045, China. lixiuxiu@163.com.
⁵ Farmland Irrigation Research Institute, CAAS, Xinxiang 453002, China. qxb6301@yahoo.com.cn.
⁶ Geosciences Department, University of Wisconsin-Parkside, Kenosha, WI 53144, USA. li@uwp.edu.

Abstract

Chitosan was used to modify a 13X molecular sieve to improve its cadmium removal capability. After being modified with 2% chitosan-acetate for 2 h at 30 °C, significant uptake of Cd²⁺ could be achieved. The uptake of Cd²⁺ on the modified 13X molecular sieve followed the Langmuir isotherms with a capacity of 1 mg/g. The kinetics of Cd²⁺ removal by modified 13X molecular sieve followed a pseudo second-order reaction, suggesting chemisorption or surface complexation. The Cd²⁺ removal with a sorbent dose of 2 g/L from an initial concentration of 100 μg/L reached more than 95% in 90 min. The equilibrium Cd²⁺ concentration was <5 μg/L, which meets the requirements of "Standards for Irrigation Water Quality" (GB5084-2005) (10 μg/L) and MCL and MCLG for groundwater and drinking water (5 μg/L) set by United States Environmental Protection Agency.

Keywords: 13X molecular sieve; cadmium; chitosan; modification; removal.