Effect of bioreduced graphene oxide on anaerobic biotransformation of nitrobenzene in an anaerobic reactor

To realize its application, in the present study, two continuous anaerobic reactors (R1 with BRGO/AS composite; R2 with AS) were employed to treat NB-containing wastewater during a long-term run. Compared with R2, the start-up time of R1 was shortened from 70 to 45 d and R1 exhibited better removal efficiency (87% of R1 and 74% of R2 with an influent NB concentration of 200 mg L −1 at hydraulic retention time = 24 h, NaCl = 3%).

Moreover, R1 exhibited better stability with over 81% NB removal efficiency within 90 d. Further study demonstrated that the presence of BRGO facilitated microorganisms to secrete extracellular polymeric substances, resulting in the higher electrochemical and dehydrogenase activities of R1 compared with those of R2.