中文摘要：

采用批量吸附实验,研究了塿土、黑土和红壤对单一SeO3^2-及其与Cu^2＋共存条件下的吸附特征,并分析了Cu^2＋添加顺序对3种土壤SeO3^2-吸附的影响,旨在为揭示土壤中铜硒复合污染中金属的迁移转化提供依据.结果表明,塿土、黑土和红壤对单一及Cu^2＋-SeO3^2-复合溶液中SeO3^2-的吸附是一个先快后慢的过程,24 h基本达到吸附平衡,且其对单一及复合溶液中SeO3^2-的吸附均符合二级动力学方程（R^2〉0.994）,说明化学吸附是主要限速步骤.3种土壤对单一SeO3^2-的吸附符合Langmuir方程（R^2〉0.937）,而先铜后硒、铜硒共同吸附处理SeO3^2-的吸附却符合Freundlich方程（R^2〉0.928）,表明加入Cu^2＋后,土壤对SeO3^2-的吸附由单分子层化学吸附转变为多分子层表面吸附.当SeO3^2-浓度为50μg·L^-1时,Cu^2＋对塿土SeO3^2-吸附无显著影响,而黑土和红壤的SeO3^2-吸附却随Cu^2＋浓度的升高而降低;且Cu^2＋的添加顺序对3种土壤SeO3^2-吸附无显著影响.当SeO3^2-浓度为200μg·L^-1时,塿土对SeO3^2-的吸附随Cu^2＋浓度的升高而下降,黑土和红壤SeO3^2-吸附量则呈先降低后略微升高的趋势,且当Cu^2＋浓度为160 mg·L^-1时,其添加顺序对3种土壤SeO3^2-吸附达到显著影响（p〈0.05）.总之,在单一及复合溶液中土壤对SeO3^2-的吸附随土壤类型而异,Cu^2＋的添加抑制了3种土壤对SeO3^2-的吸附,且Cu^2＋添加顺序对SeO3^2-吸附的影响与铜、硒离子浓度有关.

英文摘要：

The adsorption of selenite with and without Cu^2＋coexistence in loess soil,black soil and red earth were investigated through batch adsorption experiment,and the effects of Cu^2＋on the adsorption of selenite was investigated to provide theoretical basis for the transport and transformation of copperselenite pollution in soil. The results showed that the adsorption process of selenite in both single and binary solution by all three tested soils was fast initially and then slowed down,and adsorption equilibrium was reached within 24 h. In both single and binary solutions,pseudo-second-order model showed the highest agreement with the adsorption of selenite（ R^2 0. 994）,which indicated that the chemical reaction was significant in the rate controlling step. Selenite adsorption by three soils was well fitted with the Langmuir equation in single selenite solution（ R^2 0. 937）,while Freundlich equation described the isotherm of selenite adsorption for both sequential and simultaneous treatment with copper and selenite（ R^2 0. 928）. This indicated that with addition of Cu^2＋,the selenite adsorption was transformed from single-layer chemisorptions to multi-layer surface adsorption. When the initial concentration of selenite was 50 μg·L^-1,Cu^2＋had no significant influence on the adsorption of selenite in loess soil,but the selenite adsorption capacity decreased with the increase of Cu^2＋concentration for black soil and red earth. The selenite adsorption of three soils was found to be independent on the sequence of addition of Cu^2＋. When the initial concentration of selenite was 200 μg·L^-1,the adsorption capacity of selenite decreased withincreasing Cu^2＋concentration for loess soil,while first decreased and then increased slightly for black soil and red earth. When the concentration of Cu^2＋increased to 160 mg·L^-1,the addition sequence of copper affected the selenite adsorption of three soils significantly（ p 0. 05）. In summary,physicochemical property of soils can affect selenite