低分子量有机酸对红壤中硫丹释放动力学的影响  

Effects of Several Low-molecular-weight Organic Acids on the Release Kinetic of Endosulfan from Red Soil

作　　者：赵振华[1,2] 吴玉[1,2] 蒋新[3] 夏立玲[4] 倪利晓[1] 

机构地区：[1]河海大学浅水湖泊综合治理与资源开发教育部重点实验室,南京210098 [2]河海大学水文水资源与水利工程科学国家重点实验室,南京210098 [3]中国科学院南京土壤研究所土壤与农业可持续发展国家重点实验室,南京210008 [4]南京工业职业技术学院,南京210016

出　　处：《环境科学》2009年第10期3077-3081,共5页Environmental Science

基　　金：国家重点基础研究发展规划(973)项目(2002CB410805);国家水体污染控制与治理科技重大专项(2009ZX07317-007);国家自然科学基金重点项目(50839002);浅水湖泊实验室开放基金项目(2007KJ003);江苏省自然科学基金项目(BK2006169);河海大学科技创新基金项目

摘　　要：采用自行设计的动力学试验装置及平衡振荡试验,系统研究了3种低分子量有机酸（草酸、酒石酸和柠檬酸）和水对红壤中α-硫丹（-αendosulfan,αES）的动力学释放行为.结果表明,10 mmol/L的酒石酸和柠檬酸可使αES的释放百分率相对于水和草酸提高7～18个百分点,其中尤以酒石酸的效果最为明显,但水和草酸对αES的释放能力却不存在显著差异（p〉0.05）,αES的释放存在明显的快速和慢速释放期,特别在前200 mL释放较快;水和草酸对αES的释放动力学数据可由双常数方程和抛物线扩散方程较好描述,并不是代表简单表面扩散的表观一级动力学方程,而酒石酸和柠檬酸则更倾向于Elovich方程（R^2〉0.99,p〈0.000 1）,说明对这类立体结构较复杂的有机氯农药来说,影响其在水相中释放的主导因素已不是简单的颗粒表面扩散机制,还可能涉及到土壤颗粒内部的向外扩散机制、颗粒表面的活化与去活化作用、土壤颗粒表面的溶解及对包被在土壤矿物表面的固有有机质结构干扰造成的表面点位能量分布的不均匀等多种机制,使释放动力学的机制更进一步复杂化.The kinetic release behaviors of α-endosulfan from red soil with three kinds of low-molecular-weight organic acids（LMWOA： oxalate,tartrate and citrate） solution and water leaching were investigated by kinetic device designed by ourselves and batch method.The results show that： the release percentage of endosulfan from red soil by tartrate and citrate solution（10 mmol/L） can increase by 7%-18% more than that by distilled water and oxalate solution, especially for tartrate solution.There is no significant difference between distilled water and oxalate solution for the release percentage of endosulfan（p〉0.05）.There are two stages of quick and slow for the release of endosulfan from red soil,and the leaching speed is quicker especially for the initial 200 mL leaching solution.When using distilled water or oxalate solution as leaching solution,the best equations that described the kinetic release behavior of endosulfan from red soil were parabola diffuse equation and double constant equation,and weren＇t the apparent first dynamics equation that represented the simple surface diffusion mechanism.The kinetic release behavior of endosulfan in tartrate or citrate leaching system can be described by Elovich equation（R2〉0.99,p〈（0.000？1）,） it implied that the simple surface diffusion mechanism is not the primary factor that effected the release of endosulfan,which three-dimensional molecule structure is complex,from red soil in aqueous phase leaching systems,and it maybe related to the outward diffuse mechanism from soil particle,activation and deactivation function of soil particles surface,the dissolution of soil mineral surface and structure change of inherent organic matter that coating onto the soil mineral surface induced by LMW organic acid.It suggested that the tartrate and citrate induced the complication of the release mechanisms of the pesticides from red soil

关 键 词：有机酸 硫丹 动力学 释放 

分 类 号：X53[环境科学与工程—环境工程]