Cong Geng,Zhijie Liang,Fuyi Cui,Zhiwei Zhao,Chen Yuan,Jinying Du,Chuang Wang
Due to the inefficient treatment by the biotic and UV-disinfection processes in wastewater treatment plants, the broad-spectrum Fluoroquinolone antibiotics (FQs) are frequently detected in water environment around the world. In this work, the photo-degradation of three FQs (norfloxacin-NOR, ciprofloxacin-CIP, levofloxacin-LEV) by VUV/UV irradiation was investigated. The results showed that the degradation of FQs in VUV/UV irradiation system were more effective than that in UV irradiation system by enhanced the defluorination and decarboxylation . FQs could be degraded more efficiently with high temperature and low initial concentration, and the effect of flow rate was small. Initial pH played a key role in degradation of NOR and CIP. Most anions could slightly affect the FQs removal in water, except the carbonate and phosphate species. 1 O 2 and ·OH played the primary role in FQs degradation in VUV/UV system. Defluorination, decarboxylation, and piperazine ring oxidation were the main degradation pathways for three FQs degradation, but demethylation was a particular degradation pathway of LEV. Antibacterial activities of FQs aqueous sample were reduced in both VUV/UV and UV system, while the removal of antibacterial activities in the VUV/UV process were more efficient than UV process for NOR and LEV. VUV/UV system was more energy-saving for removing FQs. These results suggested that VUV/UV system is potential alternative in replacing or enhancing UV system in wastewater treatment plants for FQs removal in the future.
Liuyang He,Lixin Lv,Suresh C. Pillai,Hailong Wang,Jianming Xue,Yongfei Ma,Yanli Liu,Yulin Chen,Li Wu,Zulin Zhang,Lie Yang
Iron/copper bimetallic nanoparticles based sludge biochar (Fe/Cu-SBC) was prepared by using a modified co-precipitation route. The Fe/Cu-SBC system prepared was subsequently applied to activate periodate (IO 4 − ) to degrade diclofenac sodium (DCF) by using UV light at room temperature (25 °C). The physicochemical properties of both SBC and Fe/Cu-SBC such as morphology, physical properties, crystal structures and functional groups were examined. The type and number of surface functional groups were found to be increased and the catalytic performance was improved by the modification of Fe/Cu bimetallic nanoparticles. The influence of various parameters to evaluate the catalytic efficiency such as periodate (PI) concentration, dosage of catalysts, UV power, initial pH and coexisting anions were investigated. Under the optimized conditions (pH 6.9, UV-power 60 W, PI concentration of 5 mM and 0.1 g Fe/Cu-SBC), it was observed that 99.7% of DCF was degraded with a pseudo-first-order kinetics reaction constant 9.39 × 10 −2 min −1 . The radical scavenging experiments showed that IO 3 radicals were the predominantly reactive oxidants in the Fe/Cu-SBC/UV system. Therefore, this investigation provides a feasible alternative for the degradation of PPCPs in wastewater.
危险品化学品经营许可证（带存储）