CHEMICAL FRACTIONATION OF SOME HEAVY METALS IN SURFACE SOIL IN VICINITY OF COAL BASED SUPER THERMAL POWER PLANT IN KOTA CITY, INDIA

Abstract

ABSTRACT

 Soil samples were collected from fifteen different localities situated near coal based Kota Super Thermal Power Plant Station (KSTPS) in Kota City, India in summer season of 2019 - 20. Assessment of the soil samples was done to measure physico-chemical properties, total heavy metal concentration and chemical speciation of the heavy metals as a function of soil properties. The lability of heavy metals such as Ca, Fe, Cu, Cd, Pb and Zn in soils was measured by sequential chemical extraction procedure (SCE) to separate the metals into water soluble, MgCl₂, NH₄-acetate, hydroxylamine hydrochloride, HNO₃/H₂O₂ and HF/ HNO₃ extractable fractions. Ca and Fe associated with HF/ HNO₃ and Na-acetate extracted fractions, copper with Fe-Mn oxide and HF/ HNO₃ extracted fractions, Cd with HF/ HNO₃ and hydroxylamine hydrochloride extracted fractions, Pb with organic and Fe-Mn oxide bound extracted fraction & Zn with hydroxylamine hydrochloride and carbonate extracted fractions. The metals bound with hydroxylamine hydrochloride and HNO₃/H₂O₂ extractable fractions may be available to the plant and animals according to the pH and other physico-chemical properties of the soil.