185 nm真空紫外线照射下水中抗生素的光解

Photolytic Decomposition of Antibiotics in Water under 185 nm Vacuum Ultraviolet

185 nm真空紫外线光子具有很高的能量,不但自身具有分解有机污染物的能力,还可诱发水分子光解产生羟基自由基,氧化分解水中难降解污染物。对6种抗生素进行了185 nm真空紫外线光解,发现不但抗生素被有效降解,TOC浓度亦明显降低。重点考察了四环素的降解机理。通过对试验数据的线性回归分析,确认了四环素的降解效率是降解系数和照射时间的函数,且初始浓度越低,降解系数越高。根据静态试验数据得到,处理1 mg/L的四环素溶液时(去除率为97%)耗电量<1.833 kW·h/m^3。185 nm真空紫外线在介质中穿透率很低,水体的混合扰动对抗生素降解效果有正面影响。此外,抗生素被光解的难易程度和分子结构内的环状结构有关。

The photon of 185 nm vacuum ultraviolet has high energy,which directly decomposes organic chemicals and induces the formation of hydroxyl radical to oxidize refractory organic chemicals in water.Six antibiotics were tested using 185 nm vacuum ultraviolet,it was found that all of antibiotics were decomposed,and TOC was also decreased.Tetracycline was studied in detail.Through a linear regression analysis of the experimental data,it was confirmed that the decomposition efficiency of tetracycline was a function of decomposition coefficient and irradiation time.The lower the initial concentration was,the higher the decomposition coefficient was.According to the batch experiment,when removing 1 mg/L tetracycline at 97%removal rate,the electricity consumption was less than 1.833 kW·h/m^3.Transmittance of 185 nm vacuum ultraviolet in media was low,and mixing/disturbing had positive impact on the photolytic decomposition of antibiotics in water.The level of photolytic decomposition of antibiotics was related to the fabrication of ring structure inside the molecular.