【摘要】 采用异丙醇淬灭的方法考察了羟基自由基在光催化氧化酸性橙II过程中的产生和效能,研究了TiO2(P-25)的浓度、异丙醇的用量、酸性橙II的初始浓度、初始pH条件和天然共存离子对羟基自由基贡献率的影响。结果表明,在TiO2(P-25)浓度提高时羟基自由基的贡献率逐步提高并稳定在77.6%,异丙醇的投加量对羟基自由基的贡献率影响不大,酸性橙II初始浓度的提高则使羟基自由基的贡献率降低。在中性pH条件下羟基自由基的贡献率最高,酸性或碱性条件下较低。天然共存离子中HCO3-对羟基自由基的淬灭效应最强,F-的淬灭效应最弱。更多还原

【Abstract】 The produciton and contribution of hydroxyl radicals were evaluated using iso-propanol quenching method during photocatalytic oxidaiton of azo dye Orange II.The effects of TiO2(P-25) loading,dosage of iso-propanol,initial Orange II concentration,initial pH condition and natural occurring anionic ions on the contribution percentage of hydroxyl radicals were investigated.It indicated that an increase of TiO2 improved the contribution percentage of hydroxyl radicals and stabilized at 77.6%.The effect of iso-propanol dosage was negligible.An increased Orange II concentration declined the contribution percentage of hydroxyl radicals.Neutral pH condition was favorable for the enhancement of the contribution percentage.Among the natural occurring anionic ions,HCO-3 was the most powerful for the quenching of hydroxyl radicals while F-the weakest for the quenching process.更多还原