Biosorption and biodegradation of bisphenol A in an activated sludge system

Abstract

Research on biosorption and biodegradation of bisphenol A (BPA) in the environment is crucial for pollutant remediation. In this study, the specific biosorption rate (q _bd) and specific biodegradation rate (q _bio) of BPA in an activated sludge system with different parameters such as initial BPA concentration, pH, heavy metal and other organic carbon sources were investigated. The experimental results showed that biodegradation of BPA in the concentration range of 10–100 mg/L fitted a zero-order reaction. Kinetic parameters q _bd and q _bio of at various pH values of 6.0, 7.0, 8.0 and 9.0 were 1.20, 1.10, 1.08 and 0.54, 0.57, 0.62, 0.16, 0.74 day⁻¹, respectively. High pH greatly inhibited both biosorption and biodegradation of BPA. Kinetic parameters q _bd and q _bio at various concentrations of Cu²⁺of 0, 10 and 50 mg/L were 1.10, 1.06, 0.36 and 0.57, 0.36, 0.23 day⁻¹, respectively. When Cu²⁺ = 10 mg/L, the inhibition of biodegradation was larger than biosorption. Otherwise, when Cu²⁺ = 50 mg/L, the inhibition of biosorption was larger than biodegradation. Meanwhile, the toxicity of Cu²⁺ was reduced by chelant EDTA because of less free Cu²⁺. Glucose significantly accelerated the degradation of BPA, while p-hydroxybenzaldehyde did not.