UV/H2 O2作用下冰中苯酚的光转化及其与羟基自由基的关系

摘要

The photolysis of phenol in a UV/H2 O2 system in ice was investigated and the effects of pH value,light intensity and the initial concentration of H2 O2 on the photolysis of phenol were discussed. In addition,Hydroxyl radicals (· OH)generated during the photolysis of phenol were trapped by dimethylsulfoxide (DMSO),thus the effect of·OH radicals on the photolysis of phenol was studied. The results show that H2 O2 significantly increased ·OH generation and enhanced the photolysis of phenol in ice.Changing light intensity,pH value and the initial concentration of H2 O2 ,the photolysis rate of phenol would increased with the increase of·OH generation.The addition of NO-2 and NO-3 inhibited the generation of·OH and the photolysis of phenol.But SO2-4 had no impact on·OH generation and the photolysis of phenol.Though CO2-3 and HCO-3 decreased ·OH generation,they also had no impact on the photolysis,which might be due to the other radicals generated in the system.%在UV和 H2 O2作用下考察pH 值、光强、H2 O2初始浓度和无机离子等对冰中苯酚光解的影响,并利用二甲基亚砜(DMSO)捕获体系中生成的羟基自由基(·OH)研究·OH 对冰中苯酚光解的影响。实验结果表明：H2 O2可显著促进冰中产生·OH 及苯酚光解；改变光强、pH 值和 H2 O2的初始浓度,苯酚的光解率随体系中· OH 浓度的增加而增大；加入NO-2和NO-3可抑制体系中产生·OH 及苯酚光解；加入 SO2-4不影响体系中·OH 的产生及苯酚光解；加入CO2-3和 HCO-3可抑制体系中产生·OH,但对苯酚光解影响较小,这是由于体系中产生了其他自由基所致。