Chang Chen-Yu, Hsieh Yung-Hsu, Cheng Kai-Yuan, Hsieh Ling-Ling, Cheng Ta-Chih, Yao Kuo-Shan
Department of Life Science, Ming-Dao University, Peetow, Chang-Hua County, Chinese Taiwan.
Water Sci Technol. 2008;58(4):873-9. doi: 10.2166/wst.2008.429.
This study estimates the yield of hydroxyl radical using salicylic acid as the trapping reagent and investigates the relationship between hydroxyl radical and pH value. The formation and variation of hydroxyl radical under different pH values were evaluated using reaction products, 2,3-DHBA, 2,5-DHBA, and catechol. The formation rate of hydroxyl radical was dependent on the ratio of ferrous ion to hydrogen peroxide and pH values. The difference between various pH values was explored. The kinetics and mechanisms of hydroxyl radical reactions were established in the Fenton process. Experimental results showed that the best reaction conditions were 8.5 mM H(2)O(2), 1.25 mM Fe(2 + ), Fe(2 + )/H(2)O(2) = 0.147 at pH 3 and the formation rate constant of hydroxyl radical was 1.12 x 10(11) M(-1) s(-1).
本研究以水杨酸作为捕获剂估算羟基自由基的产率，并研究羟基自由基与pH值之间的关系。利用反应产物2,3 -二羟基苯甲酸（2,3 - DHBA）、2,5 -二羟基苯甲酸（2,5 - DHBA）和儿茶酚评估不同pH值下羟基自由基的形成与变化。羟基自由基的形成速率取决于亚铁离子与过氧化氢的比例以及pH值。探究了不同pH值之间的差异。在芬顿过程中建立了羟基自由基反应的动力学和机理。实验结果表明，最佳反应条件为8.5 mM过氧化氢、1.25 mM亚铁离子、pH值为3时亚铁离子/过氧化氢 = 0.147，且羟基自由基的形成速率常数为1.12×10¹¹ M⁻¹ s⁻¹。
