等离子体技术降解茜素红水溶液的机理研究

研究了等离子体在内电极通氧条件下降解水相中茜素红的机理。研究表明:茜素红溶液的降解率与电极位置有关,且在0和22.5mm处出现2个高值。在0和22.5mm 2种电极位置时,茜素红的降解率与等离子体电压、茜素红的浓度、溶液初始pH值、处理时间的变化规律不完全相同。在0处时,茜素红溶液经等离子体放电处理后产物主要是含氧和羟基的小分子物质;在22.5mm时,产物主要是含-CO和含-OH的芳香类物质。研究认为:在内电极位置为0处时主要是高能电子的作用,而在22.5mm处时则是O2被解离产生氧原子,氧原子和高能电子与O2和H2O溶液作用产生O3、OH·、O2-和eaq-等活性物种与茜素红作用而引起其降解。这些结果为等离子体降解有机废水的实际应用提供了信息。

Study on Degradation Mechanism of Alizarin Red in Water by Plasma Technique

Degradation mechanism of alizarin red in water with O2 has been studied by using plasma method. The results showed that the degradation efficiencies of aqueous alizarin red were different when the electrode laid on various positions, and the optimal positions were found to be at 22.5mm and 0mm. The degrada- tion mechanisms of aqueous alizarin red with these two electrode postions were different: high energy electrons attacked solvent molecules to produce active particles such as OH and eaq , which resulted in degradation of organic compounds at 0 mm; and the mainly collective action of high energy electrons and active particles was at 22.5mm. The results provided important information on the use of plasma in degradation of organic wastewater.