稀土掺杂TiO_2膨润土光催化降解中性红的研究

RTB Photocatalytic Degradation for Neutral Red

文章主要以膨润土为载体,钛酸正四丁酯和硫酸高铈为原料,采用溶胶-凝胶法制备稀土掺杂TiO2膨润土复合光催化剂,用XRD和SEM对稀土掺杂TiO2膨润土的结构和形貌进行表征,表征结果表明其具有很高的比表面积,并且存在明显的锐钛矿型TiO2晶型特征峰。研究催化剂的用量、染料的初始浓度、光照时间、pH值等因素对中性红染料脱色率的影响和它的动力学方程。实验结果表明：对于100 mg/L的中性红染料溶液,当催化剂的投加量为0.5 g;光照时间为100 min;pH=4~7时,脱色率达到99%,并且它在太阳光照射下也有较好的降解效果。催化剂重复利用5次,中性红的脱色率依然大于90%。此外,稀土掺杂TiO2膨润土对中性红染料的光催化降解符合二级动力学方程。

With bentonite as a carrier,4 n-butyl titanate and high cerium sulfate as raw material,sol-gel method was used for preparation of composites photocatalyst of rare earth-doped TiO2 bentonite（RTB）,with structure and morphology characterizing by XRD and SEM.Results showed that it has a high specific surface area,and there exists an obvious TiO2 anatase crystalline characteristics peaks.Catalyst dosage,initial dye concentration,illumination time,pH value and other factors on decolorization rate of neutral red dye as well as its dynamic equations were studied.Experimental results showed that for 100 mg/L neutral red dye solution,under the conditions of catalyst dosage 0.5 g,illumination time 100 min and pH 4~7,the decolorization rate was more than 99%,with better decolorization effect under sunlight.Reuse of catalyst for 5 times has still very high photocatalytic activity,with the decolorization of neutral red more than 90%.Photocatalytic degradation of neutral red by RTB is consistent with the kinetic equation.