新型单双槽光电催化反应器的设计及其降解性能

Design and Photocatalytic Activity of a Novel Photo-electro-chemical Catalytic Reactor with Single/Double Compartment

设计了以热氧化法制备的TiO2/Ti薄膜电极为阳极、具有较高析氢超电位的高纯石墨电极为阴极、甘汞电极为参比电极所组成的单、双槽光-电-化学催化集成反应器,并考察了该反应器对甲基红和甲基橙溶液的降解脱色性能。结果表明,单、双槽反应器均能有效的对这两种染料溶液进行降解脱色,并且在酸性及碱性条件下其降解脱色率均明显高于中性条件。双槽反应器对两种染料溶液的降解表观反应速率是单槽的2倍或以上,导致这一结果的主要原因是单槽反应器中阴极反应产生的H2O2在阳极的无效消耗。

A novel photo-electro-chemical catalytic reactor with single/double compartment was designed.TiO2/Ti thin film electrode was used as photo-anodes,graphite as cathode and a saturated calomel electrode（SCE） as the reference electrode in the reactor.The anodic compartment and the cathodal compartment was partitioned off from each other and connected through salt bridge in the dougle-compartment reactor,while the same one in the single-compartment reator.The performance on the degradation of methyl red（MR） and methyl orange（MO） were compared between these two reactors.The effects of initial pH value and accumulative concentration of H2O2 on the decolorization rate of MR were investigated.The results showed the MR was degradated effectively in these two reactors and the percent degradation were 96.9%（double-compartment） and 76.2%（single-compartment） respectively.The degradations all decreased with pH value changed from 3.0 to 7.0,while all increased with pH value changed from 7.0 to 12.0.It was more effective in the double-compartment reactor than in the single-compartment reactor during the degradation.And it was result from the higher concentration of H2O2 in the double-compartment reactor.Because in the single-compartment reactor,H2O2 generated during cathodal reaction diffused to the anode and was consumed,which could be prevented in the double-compartment reactor because of the clapboard.Under the conditions of cathodic potential Ec at-0.6 V,initial solution pH at 3.0 and initial solution concentration 30 mg·L-1,the catalytic degradation of MR and MO were both pseudo-first order reactions.