REMOVAL OF HEXAVALENT CHROMIUM BY KENDU FRUIT GUM DUST

摘要

The ability of a low cost adsorbent material, Kendu fruit gum dust (KGD), for removal of hexavalent chromium, Cr(VI), from aqueous solutions of both a synthetic and industrial (effluent) sample is successfully investigated through batch type experiments. The effects of contact time, Cr(VI) concentration, pH, adsorbent amount, and temperature on the extent of Cr(VI) removal are reported. At a lower initial concentration of Cr(VI) and a lower solution pH, the percent removal is found to be increased. A removal efficiency of 100% has been achieved. In the presence of cyanide ion the adsorption efficiency of KGD decreases. Recycling studies suggest that even after the sixth cycle, only similar to 20% loss of efficiency of KGD occurs. The adsorption process follows the Freundlich adsorption isotherm model. Another important feature of the investigation includes the studies on the characteristics and analysis of various constituents present in the newly developed absorbent material (KGD). From the thermogravimetric analysis curves of the original KGD and Cr(VI) absorbed KGD, it is observed that the thermal stability of KGD increases due to metal ion adsorption. (C) 1997 John Wiley & Sons, Inc. [References: 39]