TiO_2光催化剂在活性炭上的固定化条件优化及在枸杞多糖脱色中的应用研究

Optimization of immobilization of TiO_2 photocatalyst on activated carbon and its application in decoloration of Lycium barbarum polysaccharides

以活性炭为载体,采用溶胶-凝胶法固定TiO2光催化剂,研究了焙烧时间、焙烧温度和浸渍比(即活化剂与活性炭的质量比)三个因素对固定化效果的影响。在单因素实验的基础上,运用二次回归正交旋转组合设计对TiO2光催化剂在活性炭上的固定化条件进行优化,并建立回归模型方程,确定光催化剂的最佳固定化条件。自行研制冷电弧-光催化-吸附集成反应器,其内装填固定化后的光催化剂。用该反应器对枸杞多糖进行脱色,以枸杞多糖的脱色率和多糖保留率为指标,考察固定化效果。实验结果表明,最佳固定化条件为焙烧时间1.90h、焙烧温度510℃和浸渍比2.82:1,此条件下得到的固定化光催化剂,装填在集成反应器中对枸杞多糖进行脱色,脱色率为80.9%,多糖保留率为80.4%。

It was studied that the immobilization of TiO2 photocatalyst on activated carbon by sol-gel method was effected by the roasting time,roasting temperature and immersion ratio,which was the ratio of the activator to the activated carbon in quality.Conditions of TiO2 photocatalyst immobilization were optimized by using the quadratic regression orthogonal rotating design,which was based on the single factor experiment.The effect of immobilization was assessed in terms of the rate of decolorization and of retention for Lycium barbarum polysaccharides,by the decolorization in the integrated reactor of cold plasma-photocatalysis-adsorption,which was self-designed and manufactured.The immobilized photocatalyst was filled with the integrated reactor.The optimum immobilization conditions were：roasting time 1.90h,roasting temperature 510℃ and immersion ratio 2.82：1.Results showed that the rate of decolorization and of retention reached 80.9% and 80.4%,respectively.