【摘要】 研制出一种新型的悬浮态光电催化反应器 ,并以甲酸为研究对象 ,对该光电反应器进行了光电流增强和COD脱除的表征 .研究了光催化、电催化氧化及光电协同催化体系降解甲酸的电压 电流曲线 .数据表明 ,在相同的电压下 ,光电协同催化体系的电流远高于电化学氧化体系的电流与光催化体系中光电流之和 .同时 ,还研究了一系列物理化学因素如外加电压、光催化剂浓度和空气流量等对光电催化反应的影响 .实验结果表明 ,自行研制的新型悬浮态光电催化反应器具有良好的协同效应 ,且所需光催化剂的最佳浓度远低于其他同类光电催化反应器的最佳浓度 .在该光电催化反应器中 ,压缩空气可有效地增强传质效应和悬浮态中光激发的TiO2 颗粒在电极表面的碰撞几率 ,从而使得外电场可有效地捕获光生电子更多还原

【Abstract】 A novel poly functional slurry photoelectrocatalytic reactor, in which titanium plate was used not only as a gas distributor but also as a cathode of reactor, was designed and characterized by the photocurrent enhancement and COD removal efficiency. Both the currents of photoelectrochemical and electrochemical processes increased significantly with the increase of the applied voltage. Moreover, the former is always higher than the latter, even the sum of the latter and the photocurrent, indicating that there exists a synergetic effect in the currents. By comparison of the COD removal kinetics for the three processes, direct electro oxidation, photocatalysis and photoelectrocatalysis, an apparent photoelectrochemical synergic effect in COD removal was observed in the new reactor for treatment of wastewater containing formic acid. The effects of various factors, such as applied cell voltage, catalyst concentration and air flow, on the photoelectrocatalytic degradation of formic acid were investigated. The COD removal efficiency increases in the range of less than 5 V, then no more change exists with the increase of applied voltage, but the catalyst amount in the new reactor is very sparing, being far smaller than that in other reactors. The sparged air in the photoelectrocatalytic reactor not only can efficiently enhance the mass transfer and the collision of photoexcited TiO 2 particles in slurry with the electrode surface, but also can make electric field facilitate to capture the photogenerated electrons.更多还原