Soils Amended with Admixtures as Stabilizing Agent to Retain Heavy Metals

Abstract

In this study, the relative performance of two soils in retaining the heavy metal ions after amending them with suitable matrices has been evaluated. Red soil of Bangalore and black cotton soil of Belgaum were mixed with different percentages of lime. Heavy metal ions such as copper and chromium were used to carry out sorption studies. Experimental data was used to plot adsorption isotherms. Langmuir isotherm was found to be more suitable than Freundlich isotherm for all soil mixtures. Correlation coefficients obtained by all models fitted well in the following ranking: Elovich > Intraparticle diffusion > Pseudo second order > Pseudo first order. Surface complexation modeling was done using Visual Minteq to understand the behavior of these materials at different pH values. It can be concluded that BCS lime mixture can be used as a filter material and red soil lime mixture as the main liner material to attenuate selected heavy metals.