title: Enhanced anaerobic digestion of organic contaminants containing diverse microbial population by combined microbial electrolysis cell (MEC) and anaerobic reactor under Fe(III) reducing conditions.
abstract: Microbial electrolysis cell (MEC) devices are efficient for wastewater treatment, but its application was limited due to low anode oxidation rate. The objective of this study was to improve anode performance of a MEC combined anaerobic reactor (R1) for high concentration industrial wastewater treatment via dosing Fe(OH)3. For the first 53 days without power, the addition of Fe(OH)3 in R1 enhanced the degradation of reactive brilliant red X-3B dye and sucrose. Applying a voltage of 0.8 V in R1 resulted in a higher decolorization and COD removal through driving the redox reactions at electrodes under Fe(III)-reducing conditions. Real-time PCR and enzyme activity analysis showed that the abundance and azoreductase activity of bacteria were improved in R1. Pyrosequencing revealed that dominant populations in anode biofilm and R1 were more diverse and abundant than the common anaerobic reactor (R2), and there was a significant distinction among anode film, R1 and R2 in microbial community structure.
authors.affiliation: Key Laboratory of Industrial Ecology and Environmental Engineering, Ministry of Education, School of Environmental Science and Technology, Dalian University of Technology, Dalian 116024, China.
authors.forename: Jingxin
authors.initials: J
authors.lastname: Zhang
authors.forename: Yaobin
authors.initials: Y
authors.lastname: Zhang
authors.forename: Xie
authors.initials: X
authors.lastname: Quan
authors.forename: Shuo
authors.initials: S
authors.lastname: Chen
authors.forename: Shahzad
authors.initials: S
authors.lastname: Afzal
mesh_terms: D000693:Anaerobiosis / Q000187:drug effects; D001391:Azo Compounds; D001419:Bacteria / Q000145:classification / Q000235:genetics / Q000378:metabolism*; D001673:Biodegradation, Environmental / Q000187:drug effects; D044822:Biodiversity; D001674:Bioelectric Energy Sources / Q000382:microbiology*; D018441:Biofilms / Q000187:drug effects; D057919:Biological Oxygen Demand Analysis; D019149:Bioreactors / Q000382:microbiology*; D003116:Color; D004396:Coloring Agents; D004560:Electricity; D004566:Electrodes; D004572:Electrolysis; D007501:Iron / Q000494:pharmacology*; D009282:Naphthalenesulfonates; D009930:Organic Chemicals / Q000302:isolation & purification*; D010084:Oxidation-Reduction / Q000187:drug effects; D025341:Principal Component Analysis; D012336:RNA, Ribosomal, 16S / Q000235:genetics; D017422:Sequence Analysis, DNA; D012722:Sewage / Q000382:microbiology; D014874:Water Pollutants, Chemical / Q000302:isolation & purification*
chemical_list: D001391:Azo Compounds; D004396:Coloring Agents; D009282:Naphthalenesulfonates; D009930:Organic Chemicals; D012336:RNA, Ribosomal, 16S; C520101:Reactive brilliant red X-3B; D012722:Sewage; D014874:Water Pollutants, Chemical; D007501:Iron