Influence of various process parameters on the biosorptive foam separation performance of o-cresol onto Bacillus cereus and Cetyl Trimethyl Ammonium Bromide

Abstract

Response surface methodology was used to optimize the removal of o-cresol from aqueous solution by Bacillus cereus and Cetyl Trimethyl Ammonium Bromide based hybrid technique biosorptive foam separation. The biosorptive foam separation was carried out in two stages namely biosorption and foam separation. A minimum run resolution V central composite design with five variables (initial feed cresol concentration, pH of the feed, biosorbent dosage, time and agitation speed) for biosorption and three variables (liquid pool height, surfactant concentration and airflow rate) for biosorptive foam separation were applied to optimize the process. The optimized conditions for maximum removal of cresol for biosorption were, Initial feed cresol concentration 467mg/l, pH of the feed 6.44, biosorbent dosage 1.11g, time 5.25 days and agitation speed of 195rpm for biosorption, and that for biosorptive foam separation were liquid pool height 28.38cm, surfactant concentration 0.29% and airflow rate 1.8lpm. The results showed a good fit with the proposed statistical model for removal of o-cresol (R2 = 0.9387) for biosorption and (R2 = 0.9980) for biosorptive foam separation.