摘要
本文以名山河流域老冲积黄壤为研究对象,采用批培养法研究了原土及不同粒径微团聚体（2-0.25 mm,0.25-0.053 mm,0.053-0.002mm,〈0.002 mm）对As（Ⅴ）、P的吸附-解吸特性和P对As（Ⅴ）吸附-解吸特性的影响.结果表明：原土及不同粒径微团聚体对As（Ⅴ）与P的吸附-解吸特性相似,等温吸附均符合Langmuir和Freundlich方程,但Langmuir方程拟合效果最佳;动力学吸附均符合Elovich和双常数方程,而Elovich方程拟合效果最好,表明原土及各粒径微团聚体对As（Ⅴ）、P的吸附均以专性吸附为主,非专性吸附为辅.原土及不同粒径微团聚体对As（Ⅴ）的最大吸附量从大到小的排序为：（〈0.002 mm）〉原土〉（0.053-0.002 mm）〉（0.25-0.053 mm）〉（2-0.25 mm）,对P的最大吸附量的顺序为：（〈0.002 mm）〉（0.053-0.002 mm）〉（0.25-0.053 mm）〉原土〉（2-0.25 mm）,即粒径越小其最大吸附量越高.As、P在各粒径微团聚体上解吸量与其吸附量呈指数关系.As（Ⅴ）与P共存时,原土及不同粒径微团聚体对As（Ⅴ）的吸附量随P浓度的增加而减少,As（Ⅴ）的解吸量随P浓度的增加而增加,表明P能抑制土壤对As（Ⅴ）的吸附,而促进土壤对As（Ⅴ）的解吸,且〈0.002 mm粒径的土壤对As（Ⅴ）的吸附-解吸受P浓度的影响最小.
In this study,batch culture experiment was conducted to investigate the adsorption and desorption characteristics of arsenic（ As（ Ⅴ）） and phosphorus（ P） on various size fractions of aggregates（ 2 - 0.25 mm,0.25 - 0.053 mm,0.053 - 0.002 mm,0.002 mm） from old alluvial yellow soil. The effect of P on the adsorption and desorption characteristics of As（ Ⅴ） was also investigated. The results showed that As（ Ⅴ） and P exhibited similar adsorption and desorption characteristics on various size fractions of aggregates. The isothermal adsorption of As（ Ⅴ） and P conformed to both Langmuir and Freundlich equations,and Langmuir was the best fitting equation. In addition,their kinetic adsorption conformed to Elovich equation and double constant equation,and the Elovich was the best fitting equation. This indicated that the adsorption of As（ Ⅴ） and P were specific adsorption-based and supplemented by non-specific adsorption. The maximum adsorption of As（ Ⅴ） on various particles decreased in the following order：（ 〈0. 002 mm） 〉bulk soil （ 0.053 - 0.002 mm）〉 （ 0.25 - 0.053 mm） 〉（ 2 - 0.25 mm）. As for P,the order was（ 〈0.002 mm） 〉（ 0.053 - 0.002 mm）〉 （ 0.25 - 0.053mm） 〉bulk soil〉 （ 2 - 0.25 mm）. This suggested that the smaller the particle size was,the higher adsorption amount of P. Exponential correlations were found between the desorption amount and absorption amount for both As（ Ⅴ） and P on various size fractions of aggregates. The adsorption of As（ Ⅴ） was significantly restrained by P when they coexisted. The adsorption amount of As（ Ⅴ） decreased with the increasing concentration of P,while the desorption amount of As（ Ⅴ） increased with the increasing concentration of P. However,the influence of P on the adsorption and desorption of As（ Ⅴ） was the smallest on 〈0.002 mm fraction aggregate.
出处
《环境科学学报》
CAS
CSCD
北大核心
2016年第3期966-973,共8页
Acta Scientiae Circumstantiae
基金
四川省学术和技术带头人培养基金项目(2014)
四川农业大学学科建设双支计划(2015)~~
