壳聚糖对污染土壤中吸附态铬的解吸作用  

Enhanced Extraction of Chitosan for Chromium (Ⅵ) from Contaminated Soil

作　　者：李增新[1] 孟韵[1] 王彤[1] 张道来[2] 

机构地区：[1]青岛大学师范学院化学系,山东青岛266071 [2]国家海洋局第一海洋研究所,山东青岛266071

出　　处：《土壤通报》2009年第3期660-663,共4页Chinese Journal of Soil Science

基　　金：青岛市科技发展计划项目(05-1-NS-58)

摘　　要：选用人为污染土壤为供试样品,在土样中加入壳聚糖,采用吸附等温实验研究了壳聚糖对污染土壤中Cr(Ⅵ)的解吸作用。将壳聚糖提取液加入含Cr(Ⅵ)土壤中结果表明,壳聚糖螯合剂能提高土壤中吸附态Cr的解吸效率,增加解吸溶液中Cr(Ⅵ)的浓度。壳聚糖对污染土壤中Cr(Ⅵ)的解吸作用随着壳聚糖加入量的增大而增大,用浓度为0.4gL-1的90%脱乙酰度壳聚糖做提取液,提取液pH=5,提取平衡时间8h达到最高提取率29.4%,该吸附过程遵从Freundlich等温吸附方程;土柱淋溶实验表明壳聚糖对污染土壤中Cr的提取率最大为25.4%。In order to investigate the effects of chitosan on the various forms of Cr in synthetic contaminated soil, soluble Cr （Ⅵ） were added into polluted soil, and a method of successive extraction was chosen to determine the contents of different Cr forms. The effectiveness of adsorption isotherm experiments were conducted to investigate the effect of chitosan in removing Cr （Ⅵ）from the artificial contaminated soil. Chitosan additive enhanced the Cr （Ⅵ） extraction effectively. At a pH of 5-6, 0.4 g L-1 chitosan of 90% the degree of deacetylation, adsorption equilibrium time was about 8 h removed 29.4% of Cr （Ⅵ）from the 400 mg kg-1 of Cr （Ⅵ）soils ample. The adsorption isotherm followed Freundlieh isotherm equation. The flushing experiment indicated that the soil available chromium （Ⅵ） has been reduced less than 25.4%.

关 键 词：土壤污染 土壤修复 重金属污染 壳聚糖 Cr(Ⅵ) 

分 类 号：X131.3[环境科学与工程—环境科学]