Azo dyes are widely applied in the textile industry but are not entirely consumed during the dyeing process and can thus be discharged to the environment in wastewater.However,azo dyes can be degraded using various el...Azo dyes are widely applied in the textile industry but are not entirely consumed during the dyeing process and can thus be discharged to the environment in wastewater.However,azo dyes can be degraded using various electron donors,and in this paper,Acid Orange 7(AO7)degradation performance is investigated using methane(CH4)as the sole electron donor.Methane has multiple sources and is readily available and inexpensive.Experiments using ^(13)C-labeled isotopes showed that AO7 degradation was coupled with anaerobic oxidation of methane(AOM)and,subsequently,affected by the initial concentrations of AO7.Higher concentrations of AO7 could inhibit the activity of microorganisms,which was confirmed by the long-term performance of AO7 degradation,with maximum removal rates of 8.94 mg/(L·d)in a batch reactor and 280 mg/(L·d)in a hollow fiber membrane bioreactor(HfMBR).High-throughput sequencing using 16S rRNA genes showed that Candidatus Methanoperedens,affiliated to ANME-2d,dominated the microbial community in the batch reactor and HfMBR.Additionally,the relative abundance of Proteobacteria bacteria(Phenylobacterium,Pseudomonas,and Geothermobacter)improved after AO7 degradation.This outcome suggested that ANME-2d alone,or acting synergistically with partner bacteria,played a key role in the process of AO7 degradation coupled with AOM.展开更多
基金supported by the National Natural Science Foundation of China(Grant Nos.51178444 and 51878175)the Program for Innovative Research Team in Science and Technology in Fujian Province University(No.IRTSTFJ)and the Startup Foundation for Introducing Talent of NU1ST.
文摘Azo dyes are widely applied in the textile industry but are not entirely consumed during the dyeing process and can thus be discharged to the environment in wastewater.However,azo dyes can be degraded using various electron donors,and in this paper,Acid Orange 7(AO7)degradation performance is investigated using methane(CH4)as the sole electron donor.Methane has multiple sources and is readily available and inexpensive.Experiments using ^(13)C-labeled isotopes showed that AO7 degradation was coupled with anaerobic oxidation of methane(AOM)and,subsequently,affected by the initial concentrations of AO7.Higher concentrations of AO7 could inhibit the activity of microorganisms,which was confirmed by the long-term performance of AO7 degradation,with maximum removal rates of 8.94 mg/(L·d)in a batch reactor and 280 mg/(L·d)in a hollow fiber membrane bioreactor(HfMBR).High-throughput sequencing using 16S rRNA genes showed that Candidatus Methanoperedens,affiliated to ANME-2d,dominated the microbial community in the batch reactor and HfMBR.Additionally,the relative abundance of Proteobacteria bacteria(Phenylobacterium,Pseudomonas,and Geothermobacter)improved after AO7 degradation.This outcome suggested that ANME-2d alone,or acting synergistically with partner bacteria,played a key role in the process of AO7 degradation coupled with AOM.