改性木质纤维素对水溶液中Cr(Ⅵ)的吸附性能研究  

ADSORPTION OF Cr(Ⅵ) FROM AQUEOUS SOLUTIONS BY MODIFIED LIGNOCELLULOSE

作　　者：李晨[1] 王培丽[2] 

机构地区：[1]河南工业大学化学化工学院,河南郑州450001 [2]河南工业大学土木建筑学院,河南郑州450001

出　　处：《河南工业大学学报（自然科学版）》2014年第3期68-71,83,共5页Journal of Henan University of Technology：Natural Science Edition

基　　金：河南省教育厅自然科学基金(2010A530001)

摘　　要：在N,N-二甲基甲酰胺溶剂中以杨木木屑为原料,与环氧氯丙烷交联,然后与二甲胺反应,可以对木质纤维素改性得到阴离子交换剂.阴离子交换剂对水溶液中的Cr(Ⅵ)具有良好的吸附性能.交换剂对水溶液中Cr(Ⅵ)的吸附服从Langmuir等温吸附模型,吸附为自发过程,吸附热为-29.67 kJ·mol-1.在289 K、交换剂的用量2.0 g·L-1、初始溶液的pH≈3.0时,对Cr(Ⅵ)的最大吸附容量为144.25 mg·g-1,313 K时为118.45 mg·g-1.拟二级动力学模型能较好地描述对Cr(Ⅵ)的吸附过程.初始浓度为30、100 mg·L-1时,表观吸附活化能分别为26.30 kJ·mol-1和31.72kJ·mol-1.Lignocellulose was modified by cross-linking cottonwood sawdust with epichlorohydrin in N, N-dimethylformamide solvent, then reacting with dimethylamine to obtain an anion exchanger, which had good property in adsorbing Cr （VI） in the aqueous solutions. The adsorption conformed to a Langmuir isothermal adsorption model,and was spontaneous,and the adsorption heat was -29.67 kJ ·mo1-1. Under the condition of exchanger dose 2.0 g ·L-1 and initial pH value approximately equal to 3.0,the maximum Cr （VI） adsorption capacity was 144.25 mg ·g-l at 298 K, and 118.45 mg·g-1 at 313 K. The pseudo-secondary kinetic model could well describe the Cr （VI） adsorption process. The apparent activation energy of adsorption was 26.30 and 31.72 kJ· mol-1 respectively when the initial concentration was 30 and 100 mg·L-1.

关 键 词：木质纤维素 阴离子交换剂 吸附 Cr(Ⅵ) 

分 类 号：TS201.2[轻工技术与工程—食品科学]