INFLUENCES OF SOIL PROPERTIES ON CHROMIUM (III) SORPTION

Abstract

Soil adsorbing properties reduce sorption ability of the metal, which in turn may influence decision for remediation at contaminated sites. The objective of this study is presentation of a model based on soil properties to estimate the sorption of Cr(III) in chromium contaminated soils. Twenty uncontaminated soil samples, with properties similar to the contaminated soils were selected from around of city of Tabriz and treated with Cr as CrCl₃. A multiple regression analysis with statgraph software was used to drive an expression that related Cr sorption to common soil properties.  The results showed that four soil properties were important in determining the amount of Cr adsorbed by the soils including pH, cation exchange capacity, total inorganic carbon and clay content with nearly 80% variability in Cr sorption and a reasonable level of confidence by this model. The obtained model suggested that Cr(III) sorption was enhanced by higher soil pH, more total inorganic carbon, more clay, and higher cation exchange capacity.