Adsorption and Separation of Hexavalent Chromium by Using Adsorption Gel Prepared from Grape Residue

Abstract

Residue of grape generated during the wine production process consists of large amount of polyphenolic compounds which strongly bind heavy metal ions. An adsorption gel was prepared from such grape residue by cross linking with concentrated sulfuric acid. The adsorption behavior of the gel was investigated for Cr(III, IV) and Fe(III). The gel was found to adsorb Cr(VI) selectively over other metals. The maximum adsorption capacity of the gel for Cr(VI) was 4.72 mol/kg.