Optimization of parameters for anaerobic co-metabolic degradation of TBBPA

The addition of different carbon and nitrogen sources can promote tetrabromobisphenol A degradation to varying degrees under co-metabolism process. A kinetic model was developed to evaluate the degradation efficiency using different carbon and nitrogen sources. Sodium formate was found to be the best carbon source for tetrabromobisphenol A degradation. The degradation rate reached 96.2% with a half-life of 4.1 d. Nitrogen supplementation can also accelerate tetrabromobisphenol A degradation. Organic nitrogen is generally better than inorganic nitrogen. A response surface methodology based on the central composite design was applied to determine the optimum conditions. It showed that concentration of sodium formate, yeast extraction, tetrabromobisphenol A, and inoculum size of microorganism were important factors, and the interaction between either of two variables played different roles. Under the optimum conditions (sodium formate 11.5 mg/L, yeast extraction 2.5 mg/L, TBBPA 1.1 mg/L and inoculum size 3.4%), TBBPA degradation rate reached the maximum.