EFFECT OF VARIOUS IONIC SALTS ON THE ADSORPTION OF CR(VI) USING HUMIC ACID AS AN ADSORBENT

Abstract

Humic acids are a principal component of humic substances, which are the major constituents of soil (humas), peat and coal. It is a complex mixture of many different acids containing carboxyl and phenolate groups so that the mixture behaves functionally as a dibasic acid or, occasionally, as a tribasic acid.Humic acid (HA) was tested in the aqueous medium to remove hexavalent chromium Cr(VI) during this study. The extent of adsorption of Cr(VI) on the surface of HA was examined on the basis of increasing quantity of humic acid. An ionic interference study was also performed in order to check the effect of various ionic salts on the adsorption process. Various salts of calcium chloride (CaCl2), potassium chloride (KCl) and sodium chloride (NaCl) were tested on the adsorption of Cr(VI) while using humic acid as an adsorbent. Interactions between HA and Cr(VI) were confirmed by using Fourier transform infrared (FTIR) spectroscopy. Further characterization was also performed using UV-Visible spectroscopy and Scanning Electron Microscopy (SEM) analysis. Keywords: Humic acid, Peat, Ionic interference, Characterization, Adsorbent