Fe~(2+)协同热活化过一硫酸氢钾盐诱导自由基脱除NO的研究

在气液撞击流反应器中,研究了Fe~(2+)协同热活化过一硫酸氢钾盐诱导自由基脱除模拟烟气中的NO。考察了主要工艺参数(溶液温度、Fe~(2+)浓度、过一硫酸氢钾盐浓度、溶液pH值、NO入口浓度)对NO脱除效率的影响。分析检测了反应产物和自由基。基于不同系统的对比研究、反应产物检测和活性自由基的捕获,揭示了NO脱除过程的机制和反应路径。结果表明,提高溶液温度、Fe~(2+)浓度和过一硫酸氢钾盐浓度均提高了NO的脱除效率,而提高溶液pH值和NO入口浓度均降低了NO的脱除效率。Fe~(2+)和热对活化过一硫酸氢钾盐产生自由基有显著的协同效应。自由基氧化是NO脱除的主要路径,而过一硫酸氢钾盐直接氧化是次要的脱除路径。Fe~(2+)和热的协同活化体系具有比其他体系高得多的NO脱除率。

NO removal using oxidation of free radicals produced from Fe2+ and heat synergic activation of oxone

The NO removal using oxidation of free radicals produced from Fe²⁺ and heat synergic activation of oxone in a gas-liquid impinging stream reactor was investigated. The effects of several main process parameters (solution temperature, Fe²⁺ concentration, oxone concentration, solution pH value, NO inlet concentrations) on NO removal were examined. The reaction products and free radicals were also detected and analyzed. Based on the comparative study of different systems, detection of reaction products and capture of active free radicals, the mechanism and reaction pathways of NO removal process were revealed. The results indicate that the increase in oxone concentration, solution temperature or Fe²⁺ concentration elevates the NO removal efficiency, but the increase in the solution pH value or NO inlet concentration reduces the NO removal efficiency. A synergistic effect between Fe²⁺ and heat, which activates the oxone to generate sulfate radicals and hydroxyl radicals, was observed. It reveals that the sulfate radicals and hydroxyl radicals are the primary reactive oxidants, and oxone is the complementary oxidant for NO removal. The synergistic activation system of Fe²⁺ and heat has much higher NO removal efficiency than other systems.