Biosorption of Malathion by dry cells of an isolated Bacillus sp. S14

Abstract

The removal of Malathion, a moderately toxic organophosphate pesticide causing environmental pollution, from dilute aqueous solutions was studied. The experimental results showed that the dry cells of Bacillus sp. S₁₄ were effective in removing Malathion from solution. Biosorption equilibrium was attained within 6h. Maximum biosorption of Malathion (81.4%) was observed under the following environmental conditions, pH 6.5, temperature 25°C, dry biomass concentration 1g L^?1 at 6h. Both Langmuir and Freundlich isotherms were tested and the latter had a better fit with the data. The dried powdered cells of Bacillus sp. S₁₄ can be safely stored for 60 days at room temperature without any loss of biosorption efficiency. The results suggest that the dry cells of the isolated Bacillus sp. S₁₄ can be used as a biosorbent for an efficient removal of Malathion from aqueous solutions.