Study on adsorption behavior of Acid Orange 10 onto modified wheat husk

The present communication addresses the applicability of acid-modified wheat husk for the adsorptive removal of an anionic dye, Acid Orange 10 (AO-10) from aqueous solutions. The adsorbent was characterized by FTIR and SEM. The adsorption reached equilibrium within 30min, and the percentage removal increased with contact time, adsorbent dosage, and ionic strength. Low pH condition enhances AO-10 sorption. The experimental data for kinetic study agrees with pseudo-second-order model. Detailed investigation of experimental kinetic data indicates that overall sorption rate is governed by film diffusion mechanism. The adsorption behavior followed a Freundlich adsorption isotherm with high correlation coefficient and low (2) values. The maximum adsorption capacity was found to be 31.25mg/g. The results of thermodynamic study demonstrated that the adsorption process was spontaneous and exothermic in nature. Desorption studies revealed that the adsorbent could be reused for two successive trials without significant loss of sorption capacity.