纳米TiO_2薄膜对活性深蓝ST-2GLN染料的光催化降解研究

采用溶胶-凝胶(Sol-Gel)法,以钛酸正丁酯为前驱体,以不锈钢表面为基底,用提拉法镀膜,在400℃下高温煅烧2 h,制备出纳米TiO2薄膜光催化剂。在以波长为254 nm、8 W的紫外灯为光源、光源到溶液的距离为2 cm的条件下,对活性深蓝ST-2GLN模拟染料废水进行光催化降解试验。探讨了光照时间、初始质量浓度、TiO2提拉层数、初始pH值和H2O2的投加量等因素对脱色率的影响。结果表明:初始质量浓度为80 mg/L、TiO2提拉层数为4层、pH值为7.0的条件下,H2O2(30%)的投加量为3.0 mL,经2 h的光照,脱色率达到87%。光催化降解活性深蓝ST-2GLN染料的动力学研究表明,其降解过程是一个一级反应过程,反应速率常数为0.013 2 min-1。

Study on photodegradation of reactive dark blue ST-2GLN by nano-sized TiO2 film

Using Ti(OBu)4 as precursor,stainless as substrate,nano-sized TiO2 film photocatalyst was prepared by sol-gel dip-coating method with 2 hours of calcinations at 400 ℃.Using the UV lamp with 254 nm of wave length and 8W of intensity as the light source,when the distance from the lamp to the solution was 2 cm,a test on the said photocatalyst degrading simulant dyeing wastewater containing reactive dark bule ST-2GLN was carried out.The influences of irradiation time,initial mass concentration,layers of nano-sized TiO2 film,initial pH value,H2O2 dosage and some other factors on the decolorization rate were discussed.The results showed that: under the condition that,the initial mass concentration of the solution was 80 mg/L,the layers of nano-sized TiO2 film was 4,the pH value was 7.0,the H2O2(30%) dosage was 3.0 mL,the irradiation time was 2 h,the decolorization rate reached 87%.The research on the kinetics of photodegradation of reactive dark blue ST-2GLN showed that,the degradation was a first order reaction and the reaction rate constant was 0.0132 min-1.