腐植酸溶液的声化学降解研究

采用频率为1.8MHz的超声波在固定式声化学反应器内研究了声化学降解腐植酸的自由基氧化历程。通过采用TA溶液作为OH自由基捕获剂，吡啶溶液作HO2自由基捕获剂，以及KI溶液的I2释放法分别确定出实验条件下反应溶液中OH自由基的浓度为10^-7M，HO2自由基浓度为10^-5M及H2O2浓度为10^-5M。在此基础上研究了均相与多相催化条件下声化学降解腐植酸溶液的TOC削减情况。发现CeO2和Cu2O催化作用下腐植酸的降解效率分别较均相条件下提高40％和20％。并就反应机理和反应动力学过程进行了描述。

Degradation of humic acid in water in sonochemistry

Free radical oxidation mechanism of humic acid degradation under the irra diation of 1.8MHz ultrasound waves in a fixed sonochemical reactor was studied. It was found that using TA solution to trap the OH free radical ,pyridine to trap the HO2 free radical and KI solution to trap the H2O2 molecular, the concentration of OH and HO2 free radicals were 10-7 and 10-5 M, the H2O2 concentration was 10-5M. Based on these results, the homogeneous and heterogeneous catalysis sonochemical degradation of humic acid was also studied. It was found that in homogeneous solution the destruction rate of TOC was about 20%. While under the heterogeneous catalysis of CeO2 and Cu2O, the destruction rate of HA was higher than that in homogeneous solution by the percentage of 40% and 20% separately. The reaction kinetics process and mechanism were also de-scribed.