壅塞空化器羟自由基产量试验研究

Experimental Research of Hydroxyl Radical Production in Choking Cavitator

针对空泡溃灭瞬间产生羟自由基和氢基,而羟自由基具有强氧化性,能够与难降解有机物分子发生反应的问题,探讨了羟自由基的产量与壅塞空化器的空化强度的关系。以壅塞空化器作为空化发生元件,亚甲基蓝作为自由基捕捉剂,采用可见分光光度计检测反应前后MB(methylene blue)质量浓度的变化量,间接获得羟自由基的产量,探讨了MB初始质量浓度、背压孔当量直径和反应时间对羟自由基产量的影响。试验结果表明:背压孔当量直径为5.4 mm,亚甲基蓝溶液的初始质量浓度为12 mg/L时,自由基产量最高。

When cavities collapse, the radicals of ·OH and ·H are generated. The hydroxyl radical with strong oxidizing property can react with refractory organic compound molecule, and it has a direct relevant to cavitation effect.With choking cavitator as the cavitation generator and methylene blue（MB） as free radical scavenger, applied visible spectrophotometer to detect MB mass concentration before and after the reaction, obtained indirectly hydroxyl radical production, and investigated the influences of the initial concentration of MB, equivalent diameter of back-pressure holes and reaction time on hydroxyl radical production. The experimental results showed that the highest hydroxyl radical was acquired when the equivalent diameter of back-pressure holes was 5.4 mm and the initial concentration of MB was 12 mg/L.