过渡金属元素催化羟自由基反应机理研究

Investigation on Reaction Mechanism of Transition Metal Elements Catalyzing Hydroxyl Free Radical

针对显色剂-过渡金属元素-过氧化氢体系,用分光光度法间接测定羟自由基。通过大量试验,确定了三苯甲烷类酸性酚醌吡喃类为有效显色剂,并确定了溴邻苯三酚红-亚铁离子-过氧化氢体系测定羟自由基的最佳条件。首次推测出其最可能的反应机理为:亚铁离子催化过氧化氢产生羟自由基,羟自由基氧化溴邻苯三酚红上的羰基碳氧双键,破坏其显色的共轭结构,使其褪色。此法可作为筛选羟自由基清除剂的有效方法。

Indirect determination of the hydroxyl free radical in developed dyestransition metal H2O2 system by spectrophotometry is Investigated. Based on experiments, it is defined that triphenylmethane dyes is efficient color reagents, The optimum conditions for determination of hydroxyl radical in BPR Fe2+H2O2 is defined. The possible reaction mechanism is that Fe2+ catalyzes H2O2 to produce ·OH , and ·OH destrctures BPR color conjugate construction and let to BPR fade by oxidizing=C=O in BPR.