Dy-TiO2-膨润土复合催化剂处理茜素红、碱性品红的研究

为了在光照条件下催化降解茜素红、碱性品红染料,以膨润土为载体,钛酸正四丁酯和镝盐为原料,采用溶胶-凝胶法制备镝掺杂TiO2膨润土复合光催化剂(DTB).利用XRD、SEM对DTB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,存在明显的锐钛矿型TiO2晶型特征峰,DTB中膨润土的晶面间距由1.691 nm变为1.887 nm,增大0.196 nm.研究催化剂的用量、染料的初始浓度、光照时间、pH值等因素对茜素红、碱性品红染料脱色率的影响、降解机理和它的动力学方程.实验结果表明:pH=7时,用0.1 g DBT处理茜素红、碱性品红染料溶液,光照45 min,降解量分别达18.0 mg/g.、19.5 mg/g.相同条件下,改用太阳光源,茜素红、碱性品红的降解量也达到20 mg/g以上.催化剂重复利用2次,茜素红和碱性品红的脱色率达80％以上.DBT对茜素红、碱性品红染料的光催化降解均符合二级动力学方程.

Study of the DTB composite catalyst photocatalytic degradation for alizarin red and basic fuchsin

To degrade alizarin red and basic fuchsin in light conditions,the Dy-TiO2-bentonite(DTB)composite catalyst were prepared by bentonite as a carrier are four n-butyl titanate and dysprosium salt as raw material,the use of sol-gel method of dysprosium doped.The catalyst photocatalytic’s structure and morphology were characterization by XRD and SEM,the results showed the catalyst photocatalytic has an huge specific surface and the anatase TiO2 crystalline characteristics peaks was clearly existence.The crystal face spacing of DTB’s bentonite obviously increased 0.196 nm,from 1.691 nm to 1.887 nm.The influence of catalyst photocatalytic dosage,initial dye concentration,illumination time,pH value and other factors on decolorization rate,of alizarin red and basic fuchsin were studied.The degradation mechanism and kinetic equation of catalyst photocatalytic were studied at the same time.The data shows that under the conditions of DBT 0.1 g,illumination time 45min and pH=7,the degradation amount of alizarin red and basic fuchsin was 18.0 mg/g,19.5 mg/g.while under the same condition,use the Solar light,the degradation amount of alizarin red and basic fuchsin reached 20 mg/g or more.After the catalyst photocatalytic has been used twice,the removal rate of alizarin red and basic fuchsin was still reached 80% or more.The DTB degradation of the dynamic behavior of alizarin red and basic fuchsin line with second-order rate kinetic adsorption model.