Domestication of Bacterial Strains for Removing Toluene and H2S Simultaneously by Using Response Surface Methodology

Abstract

A central composite design experiment was conducted and the response surface methodology was performed to optimize the degradation conditions of the mixed bacterial strains that can degrade toluene and H2S. Results showed that the optimum conditions was as follows: pH 6.6, culturing temperature 29.4℃, inoculation quantity 3.0%, additive amount of toluene 3.0μL, additive amount of sodium thiosulfate 4.0g. The selected bacterial strains under the optimized conditions created a good performance of the bio-trickling filter in treating toluene and H2S simultaneously. When the inlet concentration of toluene was 600-900 mg•m-3, the toluene removal efficiency (Re) of the BTF could reach a stable level of 91.2% and the corresponding removal loading was 50.6g•m-3•h-1. Furthermore, the BTF could tolerate an inlet H2S concentration of 74 ppm with a high efficiency of 95% with the toluene Re not affected obviously.