Utilization of powdered peanut hull as biosorbent for removal of anionic dyes from aqueous solution

An untried, low cost, locally available biosorbent was investigated for its anionic dye removal capacity from aqueous solution. Powder prepared from peanut hull was used for biosorption of three anionic dyes, amaranth (Am), sunset yellow (SY) and fast green FCF (FG). The effects of various experimental parameters (e.g. initial pH and dye concentration, sorbent dosage, particle size, ion strength, contact time) were examined and optimal experimental conditions were decided. At initial pH 2.0, three dyes studied could be removed effectively. The isothermal data for biosorption followed the Langmuir and Freundlich models. The biosorption processes conformed to the pseudo-first-order rate kinetics. The results in this study indicated that powdered peanut hull was an attractive candidate for removing anionic dyes from dye wastewater. (C) 2004 Elsevier Ltd. All rights reserved.