Efficiency of rice bran for removal of organochlorine compounds and benzene from industrial wastewater

Rice bran was found to effectively adsorb several organic compounds, such a s dichloromethane, chloroform, carbon tetrachloride, trichloroethylene, tet rachloroethylene, and benzene. Equilibrium adsorption isotherms conformed-t o the Freundlich type (log-log linear). The adsorption of dichloromethane a nd chloroform by rice bran was observed over the range of pH 1-11. Therefor e, rice bran is applicable for treatment of wastewater over a wide pH range . Dichloromethane was successfully removed from water samples with an avera ge removal efficiency of 70% after 60 min when rice bran was added to water samples containing from 0.006 to 100 mg/L dichloromethane. The removal of these organochlorine compounds and benzene by rice bran was attributed to t he uptake by intracellular particles called spherosomes. Here, we report th e results of a fundamental study of the efficiency of rice bran for removal of organochlorine compounds and benzene using a batch system on the labora tory scale, and describe elucidation of the mechanism of removal of these c ompounds by rice bran.