Adsorption of chromium from steel plating wastewater using blast furnace dust

Abstract

In this work, blast furnace dust (BFD) obtained from a steel dust collector is used as low-cost adsorbent material for chromium removal from steel industrial plating wastewater. This study shows that BFD present physical and chemical characteristics, such as chemical composition, magnetic properties and particle size, suitable for application in adsorption of ions such as chromium. Different kinetics approaches and isotherms models were evaluated to describe the adsorption process. According to results, chromium adsorption follows intra-particle diffusion with adsorption in active sites. Freundlich and Dubinin-Radushkevich isotherms parameter and low free energy obtained from isotherms studies indicate that chromium adsorption occurs by of a cooperative physical adsorption process, due to the electrostatic attraction between protonated FeOH+ and HCrO4-. Although the results indicate that BFD adsorb partially the chromium, it could represent an attractive low-cost absorbent option as complementary method for removal of chromium in the steel plating wastewater treatment.