锐钛矿-金红石混合晶型TiO2降解气相苯

用溶胶-凝胶法并通过控制煅烧温度合成不同晶相比的混合晶型纳米TiO_2,在紫外光光照下降解气相苯。考察了苯初始质量浓度、紫外灯光照强度和催化剂加入量对苯去除率的影响;探究了光催化降解气相苯的动力学特征。结果表明:450℃煅烧制备的催化剂降解苯效率最高,此催化剂金红石相质量分数为6.30%;在苯初始质量浓度为74.39 mg/m~3、催化剂加入量为7 g、光照强度为2.18 klux的最佳条件下反应84 min,苯去除率达99.73%;光催化降解率与光照强度之间符合0.5级动力学特征;当催化剂加入量为3 g时,单位时间单位质量催化剂降解苯的质量最多;苯的光催化降解反应均符合一级动力学方程。

Degradation of gas phase benzene by anatase-rutile mixed phase TiO2

The mixed phase nano TiO₂ with different crystalline phases was synthesized by sol-gel method under different calcination temperature,and was used for degradation of gas phase benzene under ultraviolet light. The effects of initial benzene mass concentration,ultraviolet light intensity and catalyst amount on the benzene removal rate were investigated. The kinetic characteristics of photocatalytic degradation of gaseous benzene were investigated. The results showed that：The catalyst prepared by calcination at 450 ℃ had the highest degradation efficiency of benzene,and the mass fraction of rutile phase of the catalyst was 6.30%;The benzene removal rate reached 99.73% under the optimum conditions of 74.39 mg/m³ of initial benzene mass concentration,7 g of catalyst addition and 2.18 klux of light intensity and 84 min of reaction time;The relationship between photocatalytic degradation rate and light intensity accorded with the 0.5 level kinetic characteristics;When the catalyst amount was 3 g,the mass of benzene degraded by unit time unit mass catalyst was the most;The photocatalytic degradation of benzene was consistent with first-order kinetic equation.