低分子量有机酸对可变电荷土壤吸附铅的影响  

The Effects of Low Molecular Weight Organic Acidson Lead Adsorption by Soils with Variable Charge

作　　者：莫建军[1] MO Jianjun(College of Ecology, Lishui University, Lishui 323000, Zhejian)

机构地区：[1]丽水学院生态学院,浙江丽水323000

出　　处：《丽水学院学报》2016年第5期37-41,共5页Journal of Lishui University

摘　　要：采用平衡实验法研究了苯甲酸和水杨酸对可变电荷土壤吸附铅的影响,结果表明:供试土壤对铅的吸附服从Langmuir和Freundlich等温式,对有机酸的吸附容量较大;有机酸可以增加土壤对铅的吸附量;有机酸对铅吸附的影响随体系p H值的增加而增大,约在p H5.4(水杨酸体系)或p H4.7(苯甲酸体系)时达最大,然后逐渐减小;影响土壤对铅的吸附,可以通过有机酸改变土壤的表面电荷、土壤与有机酸形成表面三元络合物2种机制;吸附有机酸后的土壤对铅的次级吸附量的影响与竞争吸附一致,但前者的吸附量比后者大。The influence of salicylic and phthalic acids on Pb adsorption by Soils with was studied adopting equilibrium test technique. The results indicate：the adsorption behavior of the soil for Pb obeys the Langmuir and Freundlich isotherm, and the soils are high in adsorption capacity for two organic acids;the organic acids could increase the Pb adsorption amount of soil;the influence of organic acid on Pb adsorption increases with the increase of pH value in the system and reaches the maximum in pH5.4 （salicylic acid system） and 4.7 （benzoic acid system） respectively, and then decreased gradually; the organic acids could influence Pb adsorption by soil through two mechanisms———the formation of soil-organic acid-cation surface ternary complex compound and the change of surface charge of soil;the effect of the soil after organic acids adsorption on Pb secondary adsorption is almost same as that of competitive adsorption, but the adsorption of former is better than the latter.

关 键 词：可变电荷土壤 有机酸 吸附 铅 

分 类 号：X131.3[环境科学与工程—环境科学]