Copper and zinc adsorption by Chernozems of different textures

Abstract

The dependence of Cu2+ and Zn2+ adsorption by Chernozems of the Rostov region on the soil texture was examined. The thermodynamic parameters of the Langmuir equation (Kl and C∞) were calculated for all the studied samples. According to the adsorption parameters, the metal cations were arranged in the order Cu2+ > Zn2+. The adsorption of the studied heavy metals and the strength of their fixation on the surface of soil particles decreased with a decrease in the percent of the clay fraction in the particle size distribution of the soils. A correlation analysis of the relationships between the adsorption parameters and the contents of particles <0.01 and <0.001 mm in the soil samples showed that the maximum adsorption (C∞) of the metals mainly depends on the particle size, whereas the strength of adsorption is largely controlled by the chemical and mineralogical composition of the soil particles.