Degradation and mineralization of 2-chlorophenol in a single-stage anaerobic fixed-bed bioreactor

作     者：GENG YiKun LI ZhengHao YUAN Li PAN XinRong SHENG GuoPing GENG YiKun;LI ZhengHao;YUAN Li;PAN XinRong;SHENG GuoPing

作者机构：CAS Key Laboratory of Urban Pollutant Conversion Department of Applied Chemistry University of Science and Technology of China 

出 版 物：《Science China(Technological Sciences)》 (中国科学（技术科学英文版）)

年 卷 期：2020年第63卷第1期

页      面：86-95页

核心收录：

学科分类：083002[工学-环境工程] 0830[工学-环境科学与工程（可授工学、理学、农学学位）] 08[工学] 

基　　金：supported by the National Key Research and Development Program of China(Grant No.2016YFC0401101) the National Natural Science Foundation of China(Grant Nos.51738012,51708533,and51821006) the Key Research Program of Frontier Sciences,CAS(Grant No.QYZDB-SSWQDC020) the Fundamental Research Funds for the Central Universities(Grant No.WK2060190079) 

主　　题：anaerobic fixed-bed bioreactor chlorophenols degradation pathway intermediates mineralization 

摘      要：Chlorophenols(CPs) have drawn great attention due to their high toxicity and ubiquitous presence in the environment. However,the practical application of anaerobic biodegradation to remove CPs is limited by low degradation rate and incomplete mineralization. This work aims to apply a single-stage anaerobic fixed-bed bioreactor(An FBR) for complete anaerobic dechlorination and mineralization of CPs. Results showed that 2-CP removal efficiency of 99.4%, chemical oxygen demand(COD)removal efficiency of 93.0%, and methane yield of 0.22 L-CH4/g-COD could be obtained for a wide range of 2-CP loading rates(3.6–18.2 mmol L–1 d–1). Nearly complete anaerobic mineralization of 2-CP was achieved even in the absence of co-substrates,thereby greatly reducing the operation cost. This may be partly related to the attached-growth microorganisms in An FBR,allowing a higher biomass concentration and longer biomass retention time for enhanced 2-CP removal. Moreover, 16 S r RNA gene sequence analysis suggests that the An FBR harbored the potential dechlorinators(e.g., Anaeromyxobacter), phenoldegrading microbes(e.g., Comamonas and Syntrophobacter), and methanogens(e.g., Methanobacterium and Methanosaeta)after acclimation, which could cooperate effectively for 2-CP dechlorination and mineralization. Based on the identified intermediates, the possible mineralization pathway of 2-CP was proposed. These findings should be valuable to facilitate the engineering applications of An FBRs for removing CPs from wastewater.