Adsorption of recalcitrant malachite green dye from aqueous solution using cabbage waste powder.

Malachite green (MG) dye is a toxic cationic, azo soluble organic dye blamed for grievous health complications and aquatic pollution. The present study assesses the potential of cabbage waste powder (CWP) in the adsorptive removal of malachite green dye from aqueous solution. Batch experiments were designed to evaluate the impact of dye concentration, temperature. pH, adsorbent dose, particle size and contact time in dye removal. Adsorption equilibrium was realized within 80 minutes with adsorption efficiency of 92.5% at pH 8. The percentage dye removal improved with rise in time of contact, adsorbent dose and surface area to volume ratio but declined with rise in temperature. FTIR analysis established numerous functional groups of lignocellulosic compounds on adsorbent, which greatly influenced dye removal. The sorption kinetics obeyed pseudo-second order kinetic model while the equilibrium data followed Freundlich isotherm model. These results prove that the cabbage waste powder is indeed a worthwhile, overabundant and environmentally safe biosorbent for adsorptive removal of organic dyes from textile wastewaters. [ABSTRACT FROM AUTHOR]