Adsorption of methylene blue from aqueous solution using acetic acid modified rice bran

School of Applied Chemistry, Shenyang University of Chemical Technology, Shenyang 110142, China

E-mail : shzhl2000@ 163 .com

Manuscript received online 30 May 2012, revised 20 June 2012, accepted 20 June 2012

The capability of acetic acid modified rice bran (as a low cost adsorbent) for removal of methylene blue, a cationic dye, from aqueous solutions was studied. Batch experiments were conducted to study the effects of various experimental parameters such as initial solution pH, contact time, initial dye concentration and adsorbent dosage on dye adsorption and the optimal condition was selected. The kinetic data obtained from different batch experiments were analyzed using pseudo-second order equations. The applicability of the Langmuir and Freundlich models for the data was tested. Both the models adequately describe the experimental data of the adsorption of methylene blue. The equilibrium adsorption capacity (q_e) increases with increasing the initial concentration of dye and with increasing pH. The maximum adsorption capacity calculated from the Langmuir model is 25.1 mg/g for MB. The study has shown the effectiveness of modified rice bran in the removal of methylene blue from solutions.