State Key laboratory of Pollution Control and Resources Reuse, Tongji University, Shanghai, 200092, China.
J Hazard Mater. 2010 Mar 15;175(1-3):138-45. doi: 10.1016/j.jhazmat.2009.09.140. Epub 2009 Oct 2.
The parathion degradation under ultrasonic irradiation in aqueous solution was investigated. The results indicate that at the conditions in question, degradation rate of parathion decreased with increasing initial concentration and decreasing power. The optimal frequency for parathion degradation was 600 kHz. The free radical reactions predominate in the sonochemical degradation of parathion and the reaction zones are predominately at the bubble interface and, to a much lesser extent, in bulk solution. The gas/liquid interfacial regions are the real effective reaction sites for sonochemical degradation of parathion. The reaction can be well described as a gas/liquid heterogeneous reaction which obeys a kinetic model based on Langmuir-Hinshelwood model. The main pathways of parathion degradation by ultrasonic irradiation were also proposed by qualitative and quantitative analysis of organic and inorganic byproducts. It is indicated that the N(2) in air takes part in the parathion degradation through the formation of NO(2) under ultrasonic irradiation. Parathion is decomposed into paraoxon and 4-nitrophenol in the first step via two different pathways, respectively, which is in agreement with the theoretical molecular orbital (MO) calculations.
研究了超声辐射下水溶液中对硫磷的降解。结果表明，在研究的条件下，对硫磷的降解速率随初始浓度的增加和功率的降低而降低。对硫磷降解的最佳频率为 600 kHz。超声化学降解对硫磷的自由基反应占主导地位，反应区主要在气泡界面，在较大程度上，在体相溶液中。气/液界面区域是对硫磷超声降解的真正有效反应部位。反应可以很好地描述为遵循基于 Langmuir-Hinshelwood 模型的气/液多相反应动力学模型。通过对有机和无机副产物的定性和定量分析，提出了超声辐照下对硫磷降解的主要途径。结果表明，在超声辐照下，空气中的 N(2)通过形成 NO(2)参与对硫磷的降解。对硫磷在第一步中通过两条不同的途径分别分解为对氧磷和 4-硝基苯酚，这与理论分子轨道（MO）计算结果一致。
