ABSTRACT
An indigenous bacterium, Bacillus REP02, was isolated from locally sourced chromium electroplating industrial effluents. Response surface methodology was employed to optimize the five critical medium parameters responsible for higher % Cr(2+) removal by the bacterium Bacillus REP02. A three-level Box-Behnken factorial design was used to optimize K2HPO4, yeast extract, MgSO4, NH4NO3, and dextrose for Cr(2+) removal. A coefficient of determination (R (2)) value (0.93), model F-value (3.92) and its low P-value (F < 0.0008) along with lower value of coefficient of variation (5.39) indicated the fitness of response surface quadratic model during the present study. At optimum parameters of K2HPO4 (0.6 g L(-1)), yeast extract (5.5 g L(-1)), MgSO4 (0.04 g L(-1)), NH4NO3 (0.20 g L(-1)), and dextrose (12.50 g L(-1)), the model predicted 98.86% Cr(2+) removal, and experimentally, 99.08% Cr(2+) removal was found.
