光电催化氧化法降解藻毒素MCLR

Degradation of algal toxin MCLR by photoelectrocatalytic oxidation

使用DSA阳极,对光电催化氧化降解藻毒素MCLR的效能及其影响因素进行了研究。结果表明,电极表面的TiO2在光催化氧化降解MCLR的过程中发挥了明显的光催化作用。在光降解、电催化氧化、光催化氧化和光电催化氧化4个过程中,光电催化氧化对MCLR和TOC的去除率最高,分别可达100%和13%,并且光电催化氧化的去除率大于光催化氧化和电催化氧化之和,表明后两者的耦合过程产生了一定的协同作用。辐照光源和电流密度存在最佳匹配条件,分别为UVC辐照、电流密度10 mA/cm2和UVA辐照、电流密度1.0 mA/cm2,此条件下光电协同作用最显著。在光电催化氧化过程中,随极板间距增大而出现的去除率下降取决于电催化过程,而不是光催化过程;光电催化氧化MCLR的去除率随其初始浓度增加而减小。

The degradation of algal toxin microcystin-LR（MCLR） by photoelectrocatalytic oxidation and the influencing factors were studied.The results showed that TiO2 on the electrode surface present obvious photocatalytic effects in photocatalytic oxidation.Photoelectrocatalytic oxidation was the most effective process among photodegradation,photocataytic oxidation,electrocatalytic oxidation and photoelectrocatalytic oxidation in degrading MCLR and TOC,which achieved the removal efficiency of 100% and 13%,respectively.The degradation efficiency of photoelectrocatalytic oxidation was higher than that of the sum of photocatalytic oxidation and electrocatalytic oxidation,showing a certain synergetic effect.The best synergetic effect was obtained under optimum match condition of irradiation source and current density,which were irradiation UVC,current density of 10 mA/cm2 and irradiation UVA,current density of 1.0 mA/cm2.The removal efficiency in photoelectrocatalytic oxidation decreased along with the increase of the plate distance,which was correlative with electrocatalytic process rather than photocatalytic process.The MCLR removal efficiency decreased with the increase of its initial concentration in photoelectrocatalytic oxidation.