光催化反应器中臭氧产量及其影响因素研究

Yield of O_3 and Influence Factors of Photocatalytic Reactor

二氧化钛光催化降解染料废水具有反应迅速、降解彻底的优点。文章以悬浮态TiO2作为自制紫外光催化反应器(145 W,185 W)的催化剂,处理通有定量空气的清水来产生微量的臭氧。通过改变臭氧捕捉方式、初始pH值、反应时间、TiO2用量及光照强度,研究纯水中臭氧产量及pH与上述因素之间的关系,并以循环伏安法作为对照。单因素实验表明,一定程度上增大光照强度和TiO2投加量,延长反应时间或降低pH值均能增加臭氧产量。并以此设计甲基橙降解实验,浓度为20 mg/L的甲基橙溶液,以185 W紫外灯降解30 min后脱色率可达90.73%。因此,光催化反应器中,在保持降解时间和催化剂用量不变的情况下,适当的增加光照强度和降低pH能够有效的提高臭氧产率和降解效率。

It has a superiority of TiO2 photocatalysis to degrade dye wastewater for its rapid and complete characters.Suspended state titanium dioxide was selected as catalyst of ultraviolet photocatalytic reactor（145 W and 185 W） to handle pure water including fixed air in order to produce ozone.Factors such as light intensity,initial pH,time light-catalysed,amount of TiO2 and catching mode of ozone had great impact on the yield of ozone in pure water.With cyclic voltammetry as the contrast test,through single factor test,it was found that improving light intensity,increasing time light-catalysed and amount of TiO2 or reducing pH could increase the yield of ozone.In the degradation test of methyl orange with initial concentration of 20 mg/L,decoloration rate reached 90.73% after 30min lighted by 185 W ultraviolet light.Therefore improving light intensity and reducing pH could increase the yield of ozone and decoloration rate if the reaction time and dosage of catalyst were fixed.