81261-93-0Relevant articles and documents
The performance and degradation mechanism of sulfamethazine from wastewater using IFAS-MBR
Hou, Huanhuan,Duan, Liang,Zhou, Beihai,Tian, Yuan,Wei, Jian,Qian, Feng
supporting information, p. 543 - 546 (2019/09/07)
Sulfamethazine (SMZ) is an important sulfonamide antibiotic. Although the concentration in the environment is small, it is harmful. The drug residues can be transferred, transformed or accumulated, affecting the growth of animals and plants. In this study, the integrated fixed-film activated sludge membrane bioreactor (IFAS-MBR) were constructed to investigate the performance and degradation mechanism of SMZ. The addition of SMZ had a significant impact on the removal of the chemical oxygen demand (COD) and ammonia nitrogen (NH4 +-N). The optimal operating conditions were hydraulic retention time (HRT) at 10 h and solid retention time (SRT) at 80 d, respectively. On this basis, the effects of different SMZ concentrations on nutrient removal, degradation, and sludge characteristics were compared. The removal efficiency of SMZ increased with the increase of SMZ concentration. The maximum removal rate was as high as 87%. The SMZ dosage also had an obvious effect on sludge characteristics. As the SMZ concentration increased, the extracellular polymer substances (EPS) concentration and the membrane resistance both decreased, which were beneficial for the reduction of membrane fouling. Finally, seven kinds of SMZ biodegradation intermediates were identified, and the possible degradation pathways were speculated. The microbial community results showed that the microbial diversity and richness in the reactor decreased after adding SMZ to the influent. The relative abundance of Bacteroidetes, Actinobacteria, Saccharibacteria and Nitrospirae increased at the phylum level. Sphingobacteria and Betaproteobacteria became dominant species at the class level. The relative abundance of norank-p-Saccharibacteria and Nitrospirae increased significantly, and norank-p-Saccharibacteria may be the dominant bacteria for SMZ degradation.
Degradation of sulfonamides in aqueous solution by membrane anodic Fenton treatment
Neafsey, Katherine,Zeng, Xia,Lemley, Ann T.
scheme or table, p. 1068 - 1076 (2010/09/05)
Two agricultural antibiotics used heavily in agriculture, sulfamethazine and sulfadiazine, were degraded in an aqueous system by anodic Fenton treatment (AFT), an advanced oxidation technique that has been shown to be effective in degrading various pesticides but has not been applied to antibiotics. The effects of the H2O2/Fe2+ ratio, Fe2+ delivery rate, and initial contaminant concentration on the degradation of sulfamethazine by AR were determined. The optimal H2O 2/Fe2+ ratio was determined to be 10:1, and the optimal Fe2+ delivery rate was found to be between 38.9 and 54.4 μM min-1. Under these conditions, sulfamethazine was completely degraded within 10 min at a range of concentrations (18-250 μM)commonly found in manure lagoons, contaminated rivers, and groundwater. Using the same optimal conditions, the effect of pH on the degradation of sulfadiazine by AFT was analyzed, and 100 μM sulfadiazine was degraded within 6-8 min of treatment at a range of pH values (3.1-7.1) that could potentially be found in aquatic environments. Degradation products and pathways were proposed for both compounds, and it was inferred that AFT degradation products of sulfadiazine and sulfamethazine are unlikely to retain the bacteriostatic properties of their parent compounds. An aquatic toxicity test employing Lemna gibba confirmed that AFT removes the bacteriostatic properties of sulfamethazine and sulfadiazine during degradation.
