No abstract

No abstract

This study was to investigate sorption behavior of selected antibiotics in soils. The pH effect on sorption was also studied. Results showed organic matter was an important factor in the sorption of sulfamethoxazole and sulfapyridine to soil, while trimethoprim could be easily sorbed on different types of soils, and displayed a higher sorption potential than sulfamethoxazole and sulfapyridine. The extent of sulfamethoxazole sorption on selected soils was highest at low pH and decreased with increasing pH. An increase in pH was found to have no significant affect on the sorption of sulfapyradine, while sorption was found to have increased initially and decreased beyond a certain pH value for trimethoprim.

Modified anaerobic-anoxic-aerobic (A2O) technology for dye wastewater was studied. The effects of Hydraulic retention times (HRT), sludge retention time (SRT) and carbon source on treatment efficiency were discussed. Scanning electron microscopes (SEM) for different sludge and UV-visible spectrum analysis for influent and effluent were investigated respectively. The results showed that when COD of influent was 600~1200 mg/L and the dye concentration was 20~40 mg/L, HRT had the obvious effect on treatment efficiency of modified A2O system. Total treatment efficiency of the improved system was more than 90% at the optimal HRT (29 h). The dye structure was demonstrated to be changed during the process. Finally, the dye and its intermediates were transformed and mineralized respectively.

Strong anion exchange (SAX) columns and oasis HLB cartridges were combined to extract trace level oxytetracycline(OTC) and high performance liquid chromatography(HPLC) UV-detector were used to measure it in wastewater sample. The effect of mobile phase was investigated. Under the best analysis conditions, linear calibration equations were established for OTC. The linearity were in the range of 0.1-10g/mL, Correlation coefficient (R2) is about 0.9997. The recovery factors ranged from 82-92% with a relative standard deviation of 4.8-6.4%.Lab-scale experiments were conducted to investigate the sorption behavior of OTC by anaerobic sludge. Starch in the mixed liquor can decrease the adsorption capacity of OTC.