Immobilisation of tannic acid onto activated carbon to improve Fe(III) adsorption

In this study, commercially available tannic acid was employed in the modification of the surface properties of granulated activated carbon and optimum experimental parameters such as pH, contact time, initial concentration, adsorption capacity and adsorption isotherms for (a) tannic acid immobilisation onto activated carbon and (b) Fe(III) adsorption on tannic acid-activated carbon combination were determined at room temperature. Adsorption of Fe(III) on granulated activated carbon alone was also determined to compare the experimental results. Tannic acid was found effective to enhance the metal adsorption capacity of activated carbon surfaces. The Langmuir isotherm equation was found to provide reasonable well fit for the tannic acid-activated carbon and Fe(III)-tannic acid-activated carbon combinations.