Arsenite Sorption and Desorption in Soils

Autor: Elkhatib, E. A., Bennett, O. L., Wright, R. J.
Zdroj: Soil Science Society of America Journal; September 1984, Vol. 48 Issue: 5 p1025-1030, 6p
Abstrakt: A linear form of the Freundlich isotherm was used to describe arsenite [As(III)] sorption by the A and B horizons of five West Virginia soils. Arsenite sorption conformed to the Freundlich isotherm over the entire concentration range for all the soils. Simple correlation coefficients and multiple regression equations were used to relate soil properties to parameters of the Freundlich equation. Iron oxide percentage and pH were the soil properties most closely related to parameters of As(III) sorption. The rate of As(III) sorption by the A and B horizons of an Upshur soil was rapid initially and decreased with time. A modified form of the Freundlich equation was used to explain the As(III) sorption rate data. Arsenite sorption was not reversible; only a small amount of the sorbed As(III) was released after five desorption steps. The modified Freundlich equation was also used to describe As(III) desorption rate. Simple and multiple regression calculations indicated that iron oxides and pH were correlated with the rate of As(III) desorption by the investigated soils.
Databáze: Supplemental Index