在TiO2催化剂上苯酚光催化氧化反应研究2-多相光催化氧化与直接光解反应的比较

在ＴｉＯ２悬浆体系，中压汞灯作用下，通过苯酚降解过程中总碳浓度变化及二氧化碳生成速度的变化规律，研究了光催化氧化与直接光解反应的不同，并着得比较了当反应条件如催化剂量，气相氧浓度以及光强度变化对两种反应的影响。实验结果证明了两种反应的历程和产物各不相同，多相光催化氧化更有利于有机物分子的降解，而光解作用会引起聚合反应，同时也说明充分利用太阳能不仅是开发光催化水处理技术的重要途径，也是抑制直接光解加

COMPARATIVE BETWEEN HETEROGENEROUS PHOTOCATALYTIC OXIDATION AND DIRECT PHOTOLYSIS OF PHENOL IN AQUEOUS SOLUTION

Comparison between heterogeneous photocatalytic oxidation with TiO₂ slurry and direct photolysis of phenol have been investigated by means of monitoring the total carbon concentration and starting material during the reaction processes.The results clearly indicated that both processes followed different pathways.In photocatalysis oxidation the phenol was degraded into smaller molecular compounds.In contrast, in direct photolysis the dimmer or polymer reactions of phenol were brought as evidence showing that moleculars of the products are bigger than starting material.The influences of reaction conditions such as catalysts dose, the oxygen concentration, and illumination intensity on the reaction rate were investigated.In addition, it was shown that in visible light region the reaction rate of the photocatalytic oxidation is much faster than that of the direct photolysis, indicating the advantage of developing solar photocatalytic oxidation facilities for commercial applications on wastewater treatment.