Advanced biodegradation process of atrazine in the peroxidase-mediated sequencing batch reactor (SBR) and moving-bed SBR (MSBR): mineralization and detoxification

AbstractThe advanced biodegradation process of atrazine was stimulated with hydrogen peroxide (H2O2) in a sequencing batch reactor (SBR) under different operational conditions due to in situ generation of H2O2-peroxidase. The complete biodegradation and mineralization of 50  mg/L atrazine was achieved in the SBR with a biomass concentration of 328 mg/L stimulated with 10 mM of H2O2. The presence of H2O2 in the SBR induced the generation of H2O2-peroxidase resulted in acceleration of atrazine biodegradation. Adding moving media to the SBR system and converting it to the MSBR considerably improved the rate of atrazine biodegradation and mineralization under H2O2 mediation. The highest specific utilization rate of atrazine in the SBR operated at the biomass concentration of 55  mg/L was 19.4 mg/gbiomass.h, while it was 33.5  mg/gbiomass.h in the MSBR operated at the biomass concentration of 37  mg/L. The low ATZ removal along with no peroxidase activity in the bioreactor in absence of H2O2 clearly ideated that the biodegradation and mineralization of ATZ was considerably mediated by H2O2-peroxidase enzyme. The toxicity of atrazine solution decreased markedly when treated in the MSBR under optimum conditions. Accordingly, the MSBR stimulated with H2O2 is an efficient and thus promising process for biodegradation of recalcitrant compounds.
Source: Journal of Environmental Health Science and Engineering - Category: Environmental Health Source Type: research