摘要

Wheat bran was modified with citric acid and utilized as a low cost adsorbent to remove methylene blue, a cationic dye from aqueous solutions. Batch experiments were carried out to study the effect of various experimental parameters such as initial solution pH, contact time, initial dye concentration and adsorbent dosage on methylene blue adsorption, and the optimal condition was selected. Kinetics studies showed that methylene blue adsorption process obeyed pseudo-second order rate equation. 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 maximum adsorption capacity calculated from the Langmuir model is 25.6 mg/g for methylene blue. The study has shown the effectiveness of modified wheat bran in the removal of methylene blue from aqueous solutions.