低分子量有机酸对棕壤吸附Cr(Ⅵ)特性的影响研究  

Effects of Low Molecular Weight Organic Acids on Brown Soil Adsorption Characteristics of Cr(Ⅵ)

作　　者：王鑫[1,2] 梁成华[1] 陈辉[2] 李述贤[2] 尹岩[1] 

机构地区：[1]沈阳农业大学土地与环境学院,辽宁沈阳110866 [2]沈阳环境科学研究院,辽宁沈阳110016

出　　处：《环境科学与技术》2014年第8期13-16,共4页Environmental Science & Technology

基　　金：国家环境保护公益性行业科研专项(2011467039)

摘　　要：采用一次平衡法研究Cr（Ⅵ）在棕壤中的吸附解吸行为,并针对pH值和土壤有机质对吸附反应的影响进行研究。结果表明,Langmuir方程和Freundlich方程可以很好地拟合Cr（Ⅵ）在土壤中的吸附,Cr（Ⅵ）在土壤中的最大吸附为204.08 mg/kg。在pH值3.0~7.0范围内,供试土壤吸附量随pH值增加而减少;土壤对Cr（Ⅵ）的吸附量与土壤中的有机质含量呈负相关。在酸性条件下,低分子量有机酸抑制土壤对Cr（Ⅵ）的吸附。加入供试有机酸后土壤对Cr（Ⅵ）最大吸附量的顺序为：无有机酸〉乙酸〉草酸〉酒石酸〉柠檬酸。柠檬酸更适用于Cr（Ⅵ）污染土壤中污染因子的萃取和淋洗。One equilibrium method was used to study the sorption- desorption behavior of Cr（ Ⅵ ） in brown soil, and the effects of pH value, soil organic matter on sorption were studied. Results indicated that the Langmuir equation and Freundlich equation can well fit Cr（ Ⅵ ） adsorption in soil, with the maximum adsorption amount of Cr（ Ⅵ ） in soil as 204.08 mg/kg. In the pH range of 3.0-7.0, the sorption quantity reduced with the increase of pH value of the tested soil. Soil sorption of Cr（Ⅵ） was observed to be negatively correlated with the content of organic matter in soil. Under acid condition, low molecular weight organic acids inhibited soil sorption of Cr （ Ⅵ ）. In the series of tested organic acid soils, the maximum sorption of Cr（ Ⅵ ） was in the order as no organic acid〉acetic acid〉oxalic acid〉tartaric acid〉citric acid, so citric acid is more suitable for pollutant extraction and leaching of Cr（ Ⅵ ） polluted soil.

关 键 词：Cr(Ⅵ) 棕壤 吸附-解吸 有机酸 

分 类 号：X131.3[环境科学与工程—环境科学]