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. (C) 2020 Elsevier B.V. All rights reserved.

Automated summary

This study found that waste zero-valent iron can shorten the acclimation time of microorganisms in the presence of bisphenol A, improve the removal efficiency of bisphenol A, and increase the production of extracellular polymeric substances. Additionally, the microbial community structure in SBBR-ZVI+BPA was more diverse, and the abundance of bisphenol A biodegradation strains could be enhanced.