Mechanism for Cu^(2+) Sorption on Palygorskite  

作　　者：CHENTian-Hu PENGShu-Chuan XUHui-Fang SHIXiao-Li HUANGChuan-Hui 

机构地区：[1]SchoolofNaturalResourcesandEnvironmentalEngineering,HefeiUniversityofTechnology,Hefei230009（China） [2]DepartmentofGeologyandGeophysics,UniversityofWisconsin,Madison,WI53706（USA）

出　　处：《Pedosphere》2005年第3期334-340,共7页土壤圈（英文版）

基　　金：1 Project supported by the National Natural Science Foundation of China (Nos. 40472026 and 40072017).

摘　　要：A single-factor experiment of copper ion adsorption on pure palygorskite was carried out to understand the Cu2+ sorption of palygorskite—an important clay mineral in soil and sedimentary rock. In addition, pH of the solution and the surface microstructure of palygorskite were investigated before and after adsorption. The experimental results indicated that efficiency of Cu2+ removal was related to the oscillation rate of the specimen shaker, sorption time, initial pH value and the amount of adsorbent added. Palygorskite induced Cu2+ hydrolysis and interaction between copper hydroxide colloids and palygorskite surfaces, as observed with transmission electron microscopy (TEM), were the main contributions to palygorskite removal of Cu2+. This mechanism was different from adsorption at the mineral-water interface. It was proposed that surface hydrolysis of palygorskite raised the alkalinity of the palygorskite-water interface and suspension system. Thus, the induced pH of the solution was then high enough for Cu2+ hydrolysis on the mineral surface and in solution.A single-factor experiment of copper ion adsorption on pure palygorskite was carried out to understand the Cu2+ sorption of palygorskite—an important clay mineral in soil and sedimentary rock. In addition, pH of the solution and the surface microstructure of palygorskite were investigated before and after adsorption. The experimental results indicated that efficiency of Cu2+ removal was related to the oscillation rate of the specimen shaker, sorption time, initial pH value and the amount of adsorbent added. Palygorskite induced Cu2+ hydrolysis and interaction between copper hydroxide colloids and palygorskite surfaces, as observed with transmission electron microscopy (TEM), were the main contributions to palygorskite removal of Cu2+. This mechanism was different from adsorption at the mineral-water interface. It was proposed that surface hydrolysis of palygorskite raised the alkalinity of the palygorskite-water interface and suspension system. Thus, the induced pH of the solution was then high enough for Cu2+ hydrolysis on the mineral surface and in solution.

关 键 词：copper ion PALYGORSKITE sorption mechanism transmission electron microscopy (TEM) 

分 类 号：X703[环境科学与工程—环境工程]