Removal of Cd(II) and Pb(II) from soil through desorption using citric acid: Kinetic and equilibrium studies

来源期刊:中南大学学报(英文版)2017年第9期

论文作者:顾凡 唐强 周婷 王艳 褚嘉明

文章页码:1941 - 1952

Key words:Cd(II) and Pb(II); desorption; citric acid; mechanism; simulation

Abstract: The desorption test was conducted to evaluate the desorption behavior of Pb(II) and Cd(II) using citric acid. The influential factors that were considered included initial Pb(II), Cd(II) contamination levels in soil, concentration of citric acid, reaction time, soil pH value and ionic strength. The test results indicated that the desorption was a rapid reaction (less than 6 h), and the removal percentages of Cd(II) and Pb(II) increased with the increasing contamination levels, concentration of citric acid and the addition of Na+, Ca2+, Cl-. However, the desorption of Pb(II) and Cd(II) decreased with the addition of SO42– because of the precipitation in the form of MSO4(s). The high pH condition indicated a negative effect on Pb(II) desorption. The removal percentage decreased from 71.39% to 10.9% as pH increased from 2 to 10.8. The desorption behavior predicted by Visual MINTEQ was in good agreement with the experimental testing result. The results of X-ray diffraction (XRD), X-ray fluorescence (XRF) and N2-BET adsorption test demonstrated that the desorption behavior of heavy metals (i.e., Pb(II) and Cd(II)) was controlled by the affinity of sorption sites for heavy metals, the competition of H+, Ca2+, Na+, Cl and the chelating of organic ligands.

Cite this article as: TANG Qiang, ZHOU Ting, GU Fan, WANG Yan, CHU Jia-ming. Removal of Cd(II) and Pb(II) from soil through desorption using citric acid: kinetic and equilibrium studies [J]. Journal of Central South University, 2017, 24(9): 1941–1952. DOI: https://doi.org/10.1007/s11771-017-3602-x.

有色金属在线官网  |   会议  |   在线投稿  |   购买纸书  |   科技图书馆

中南大学出版社 技术支持 版权声明   电话:0731-88830515 88830516   传真:0731-88710482   Email:administrator@cnnmol.com

互联网出版许可证:(署)网出证(京)字第342号   京ICP备17050991号-6      京公网安备11010802042557号