Okada Akira, Sekiguchi Kazuhiko, Sankoda Kenshi
Graduate School of Science and Engineering, Saitama University, 255 Shimo-Okubo, Sakura, Saitama 338-8570, Japan.
Graduate School of Science and Engineering, Saitama University, 255 Shimo-Okubo, Sakura, Saitama 338-8570, Japan.
J Hazard Mater. 2022 Feb 5;423(Pt B):127221. doi: 10.1016/j.jhazmat.2021.127221. Epub 2021 Sep 15.
We developed a new method for removing gaseous substances by using high frequency (200 kHz) ultrasonic irradiation of water, and the effects of ultrasonic irradiation on gas-phase toluene were evaluated quantitatively for the first time. The removal ratio of gaseous toluene increased with increasing ultrasonic power, but the reaction was inhibited by the addition of radical scavengers, indicating that ultrasonic irradiation not only accelerated the dissolution of gaseous toluene but also induced toluene decomposition. The contribution made by OH radicals to the decomposition of gaseous toluene at the gas-liquid interface was confirmed by the difference in removal ratios between addition of KI and addition of tert-butyl alcohol. The toluene removal mechanism was investigated by studying the logarithmic plots for toluene concentration at specified times. The results of this study clearly showed the promotion of gaseous toluene dissolution and the reaction via OH radicals at the gas-liquid interface by sonophysical and sonochemical effects with both effects contributing to the removal of gaseous toluene. Furthermore, the total organic carbon concentration in the aqueous phase increased with increasing reaction time, indicating that the toluene degradation products were trapped and decomposed into low-molecular-weight organic compounds in the aqueous phase.
我们开发了一种通过对水进行高频（200kHz）超声辐照来去除气态物质的新方法，并首次定量评估了超声辐照对气相甲苯的影响。气态甲苯的去除率随超声功率的增加而提高，但添加自由基清除剂会抑制该反应，这表明超声辐照不仅加速了气态甲苯的溶解，还诱导了甲苯的分解。通过添加KI和添加叔丁醇时去除率的差异，证实了OH自由基对气液界面处气态甲苯分解的贡献。通过研究特定时间甲苯浓度的对数图来探究甲苯的去除机理。本研究结果清楚地表明，通过声物理和声化学效应，气态甲苯在气液界面处的溶解及通过OH自由基的反应得到促进，这两种效应都有助于气态甲苯的去除。此外，水相中总有机碳浓度随反应时间的增加而升高，这表明甲苯降解产物被捕获并在水相中分解为低分子量有机化合物。
