Fixed-bed adsorption of Reactive Orange 84 dye onto activated carbon prepared from empty cotton flower agro-waste

Abstract

Abstract The adsorption potential of empty cotton flower agro-residue based activated carbon (CFAC) to adsorb Reactive Orange 84 (RO84) dye from aqueous solution was studied using packed-bed adsorption column. The breakthrough curve characteristics were highly influenced by process variables like influent flowrate, inlet RO84 dye concentration and CFAC bed height. The findings indicated that higher value of dye concentration and bed height were favorable but high influent flowrates was unfavorable for adsorptive removal of RO84 dye. The maximum adsorption capacity of column was found to be about 720 mg of RO84 per 4.67 g of CFAC adsorbent for initial concentration, flowrate and bed height of 200 mg L−1, 15 mL min−1 and 5 cm, respectively. Thomas, Yoon–Nelson and Bed Depth Service Time (BDST) models were applied to calculate kinetic parameters of the laboratory fixed-bed adsorption column. Based on error analyses, Thomas model and BDST model fitted well than Yoon–Nelson model. The study concluded that CFAC is an effective adsorbent for adsorption of RO84 dye using fixed-bed adsorption column.