辣根过氧化物酶处理酚和氯酚的催化特性研究

Kinetic Study on the Removal of Toxic Phenol and Chlorophenol from Waste Water by Horseradish Peroxidase

为了研究辣根过氧化物酶处理酚和氯酚的动力学过程，采用人工配水试验，测定了ｐＨ对酶催化反应的影响、Ｈ２Ｏ２抑制酶催化反应的动力学参数和不同底物的酶催化反应动力学参数．结果表明，在试验的ｐＨ范围内，ｐＨ为９时过氧化物酶对苯酚和对氯苯酚的去除效率最高，分别达到９９．５％和９５％．在较低浓度时污染物去除效率随Ｈ２Ｏ２浓度的升高而增加，较高浓度Ｈ２Ｏ２对酶催化反应有一定的抑制效应，但这种抑制作用对酶促反应的影响不大．对氯苯酚、苯酚和间氯苯酚的酶催化反应米氏常数Ｋｍ依次增加，对酶的亲和性逐渐降低，间氯苯酚最难去除．根据酶反应动力学特征判定，辣根过氧化物酶催化酚形成自由基的氧化反应属于乒乓双双反应机制．

The removal of phenol and chlorophenol from waste water catalyzed by horseradish peroxidase was studied in this paper to understand the kinetic features of this reaction.The effects of pH,H2O2 concentration and substrate type on the removal of pollutants were discussed in detail.The results showed that the optimum pH for the removal efficiency of phenol and chlorophenol was 90 in the test pH range of 50 to 90.The results also indicated that there was an optimum H2O2 concentration for pollutants removal catalyzed by horseradish peroxidase and H2O2 at concentrations higher than the optimum value had inhibition effect on pollutant removal.But the inhibition effect of higher H2O2 concentrations was very small and had little influence on the reaction.Several substrates were compared on their affinity with horseradish peroxidase according to the kinetics parameters of reactions.The results showed that phenol and 4chlorophenol were more easy to be removed than 3chlorophenol.It was also concluded in this paper that oxidation reaction catalyzed by horseradish peroxidase had the characteristic of PingPang reaction.