Removal of bisphenol A by waste zero-valent iron regulating microbial community in sequencing batch biofilm reactor

The removal of bisphenol A (BPA) by waste zero-valent iron (ZVI) regulating microbial community in sequencing batch biofilm reactor (SBBR) was investigated. Compared with SBBR_-BPA, the acclimation time of microorganisms in the presence of waste ZVI and BPA (SBBR_-ZVI+BPA) decreased from 56 d to 49 d. During stable operation period, BPA was removed completely at 150th min and 100th min in the SBBR_-BPA and SBBR_-ZVI+BPA, respectively. The optimal initial pH and BPA concentration in the SBBRs were respectively 8.0 and 10 mg/L. The composition and content analysis of extracellular polymeric substances (EPS) using fluorescence spectrometer showed that the yield of EPS was enhanced by the addition of ZVI. The analysis of microbial community structure in the SBBRs using Illumina Miseq sequencing method indicated that the indexes of ACE, Chao1 and Shannon were higher and Simpson index was lower in the SBBR_-ZVI+BPA. Moreover, the abundance of BPA biodegradation strains was increased in the presence of ZVI. This study provided a promising method with low cost of effectively removing BPA from wastewater.