过氧化氢存在下电化学高级氧化法处理苯酚废水

Electrochemical advanced oxidative degradation of phenol in the presence of hydrogen peroxide

以苯酚的电化学氧化为模型反应,在Ti/RuO2-IrO2阳极、石墨阴极体系上,外加过氧化氢并控制电压为1.0 V进行电化学氧化降解研究,以提高活性氧浓度和减少氧的析出,提高氧化降解效率.结果表明,苯酚的直接电化学氧化作用可以忽略不计,而主要发生的是有自由基参与的高级氧化过程.过氧化氢首先在电极上氧化或还原产生HO2.和HO.自由基,这些自由基进攻苯酚,可以使绝大多数的苯酚转化为苯醌,并进一步开环生成分子量更小的脂肪酸,苯酚的去除率可以达到85%.

This thesis described the processes for the electrochemical oxidation of phenol in the presence of adscititious H2O2 at a Ti/Sn-Sb2 O3 tabulate anode and a graphite cathode at lower anode potential. The purpose was to reduce the consuming energy by way of increasing concentration of intermediate oxygen species and decreasing the production of oxygen. The experiment facts indicated that the direct electrochemical oxidation of phenol was insignificant and the intermediate oxygen radicals were the main oxidizing agents resulting in phenol degradation. H2O2 can be easily electro reduced or oxidized to produce active oxygen free radical HO2·and HO· , which aroused the conversion of phenol into benzoquinone and short chain acids. Phenol removal was much higher than that in the absence of H2O2.