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以全氟磺酸树脂(perfluorosulfonated resin,PSR)溶液和TiO2溶胶为原料,通过重铸法制得TiO_2/Nafion杂化薄膜;用含5%TiO_2的杂化离子膜分解有机污染物三氯联苯溶液,采用气相色谱质谱联用仪(GC-MS)分析光催化降解过程以及降解产物。结果显示:浓度为640μg/L的2,4,5-三氯联苯光催化降解5 min后,其降解率为91.1%,15 min后接近完全降解;对浓度为6.4 mg/L的2,4,5-三氯联苯光催化降解5 min后分析可知,在降解过程中,2,4,5-三氯联苯同时存在异构反应和脱氯反应,且以脱氯反应为主:在脱氯反应中,邻位脱氯较先发生。反应过程推断为:2,4,5-二三氯联苯异构化生成2,4,6-三氯联苯,二者又通过邻位脱氯分别生成3,4-二氯联苯和2,4-二氯联苯。
TiO 2 / Nafion hybrid films were prepared by recasting method using perfluorosulfonated resin (PSR) solution and TiO2 sol as raw materials. The organic pollutants trichlorobiphenyl solution was decomposed with hybrid ion-exchange membrane containing 5% TiO 2 The photocatalytic degradation and degradation products were analyzed by gas chromatography-mass spectrometry (GC-MS). The results showed that the degradation rate of 2,4,5-trichlorobiphenyl at the concentration of 640μg / L for 5 min was 91.1% after 5 min, and almost completely degraded after 15 min. The concentration of 2,4,5- After 5 min photochemical degradation of 4,5-trichlorobiphenyl, it was found that 2,4,5-trichlorobiphenyl had both isomerization and dechlorination reactions at the same time, and dechlorination was the main reaction. In the dechlorination reaction, ortho-dechlorination occurs first. The reaction process is inferred as follows: isomerization of 2,4,5-trichlorobiphenyl to 2,4,6-trichlorobiphenyl, which in turn produces 3,4-dichlorobiphenyl and 2,4-Dichlorobiphenyl.