Adsorption mechanism of Cd(ll)by calcium-modified lignite-derived humin in aqueous solutions
Ping Wang
Zhanbin Huang
Zhanyong Fu
Peng Zhao
Zeshen Feng
Yao Wang
Fangze Li
School of Chemical and Environmental Engineering,China University of Mining and Technology-Beijing,Beijing 100083,China
摘要：Lignite-derived humin(CHM)was extracted from raw coal in Heihe City,China,producing calcium-modified lignite-derived humin(Ca-CHM)by Ca(OH)2.The physical and chemical performances of CHM and Ca-CHM were analyzed with SEM,13C spectra and XPS techniques.The results show that Ca-CHM exhibited weaker aliphatic,more aromatic polar compared with CHM,which improves the adsorption capacity for Cd(II).XPS analysis indicates that Ca(II)has been loaded onto Ca-CHM successfully after modification.This batch adsorption experiments report the adsorption performance of CHM and Ca-CHM for Cd(II).The adsorption process of CHM and Ca-CHM for Cd(II)conform to pseudo-second-order model,which is chemical adsorption,and the adsorption data presented good fits to the Langmuir model.The maximum adsorp-tion amount(Qm)of Cd(II)onto CHM and Ca-CHM by the Langmuir model is 15.29 mg/g and 41.84 mg/g,respectively.Based on the results of SEM,13C spectra,and XPS analysis,we concluded that the main adsorption mechanism of Ca-CHM on Cd(II)was ion exchange of Cd(II)for Ca(II),static-adsorbed and surface complexation.Therefore,Ca(II)can be loaded on the surface of Ca-CHM by chemical modification,improving the adsorption capacity of materials in aqueous solutions.
机标关键词：mechanismmodifiedadsorptionaqueouscalciumhuminlignite-derivedsolutions
论文发表日期：2022-06-28
在线出版日期：2025-08-15（本平台首次上网日期，不代表文献的发表时间）
页数：11( 221-231 )
英文信息