土壤中丁草胺的吸附动力学  

The kinetics of butachlor sorption in soils

作　　者：刘忠珍[1] 何艳[1] 吴愉萍[1] 汪海珍[1] 徐建明[1] 

机构地区：[1]浙江大学土水资源与环境研究所,浙江杭州310029

出　　处：《中国环境科学》2007年第4期493-497,共5页China Environmental Science

基　　金：国家杰出青年科学基金资助项目(40425007);国家自然科学基金资助项目(40671092);国家重点基础研究发展计划973项目(2005CB121104)

摘　　要：采用平衡吸附法,以我国12种不同类型的土壤为介质,对丁草胺在土-水界面的吸附动力学进行了研究.结果表明,土壤对丁草胺的吸附在24h内可基本达到表观平衡,但有机碳(TOC)含量低(<5g/kg)的土壤需较长时间(60h);丁草胺平衡吸附量与TOC和无定型氧化铁含量呈正相关,其相关系数分别为0.889,0.692;丁草胺在土壤中的吸附过程受复杂的多反应机制控制,可分为快速和慢速吸附阶段,在这一过程中,TOC控制着丁草胺的吸附速率.黏粒和CEC也有一定程度的影响,这3个因素可以解释77.8%吸附速率的变化.结合运用Elovich方程和双常数方程,可以较好地描述土壤对丁草胺的吸附动力学过程.The kinetics ofbutachlor sorption on 12 Chinese typical soils was investigated by batch equilibrium technique. Butachlor sorption by soils apparently equilibrated in 24h, but the soil with special low total organic carbon （TOC） content （〈5g/kg） needed longer time （60h）. The capacity ofbutachlor sorption was positively related to the TOC content （r =0.889） and amorphous Fe203 content （r =0.692）. The processes of butachlor sorption could be divided into fast and slow reaction stages. Total organic carbon was the major factor in influencing the rate of butachlor sorption, meanwhile, clay and CEC also affected in certain degree. Total organic carbon, clay and CEC could describe 77.8% of the variability in sorption rate. Kinetics ofbutachlor sorption could be fitted well by the Elovich equation and the dual constant equation, which could be better understood when both of the equations were used together.

关 键 词：丁草胺 动力学吸附 TOC 无定型氧化铁 黏粒 

分 类 号：X53[环境科学与工程—环境工程]