稀土掺杂介孔二氧化钛的制备工艺及其在印染废水处理中的应用

发布时间：2018-10-09 17:49

【摘要】：论文的主要研究内容包括：1、本论文的前驱体是钛酸四丁酯,硝酸作pH调节剂,溶剂为无水乙醇,抑制剂为乙酰丙酮,并加入适量去离子水,模板剂选用双十六烷基二甲基溴化铵,采用溶胶-凝胶法在室温下制备介孔TiO2。通过大量实验总结出了制备稳定溶胶的工艺条件及影响介孔Ti02光催化性能的主要因素。并对其结构和形貌进行X射线衍射(XRD)、物理氮气吸附量、扫描电子显微镜(SEM)等表征。2、以六水硝酸铈为铈源进行掺杂,以六水硝酸钐为钐源进行掺杂,采用溶胶-凝胶法进行稀土元素掺杂改性,制备出了高活性的铈掺杂介孔Ti02、钐掺杂介孔Ti02半导体材料,利用罗丹明B为目标污染物,研究不同掺杂量、焙烧时间、焙烧温度对光催化性能的影响,对其进行光催化效果评价。采用X射线衍射、扫描电子显微镜、物理氮气吸附量等手段对其进行表征。结果表明：所制得样品均为锐钛矿相二氧化钛,掺杂后的光催化剂对罗丹明B降解效果有了明显的增强,表明掺杂铈、钐的介孔二氧化钛对染料废水的处理能力大大加强。3、在以上实验的基础上,采用改性的溶胶-凝胶法制备出了高活性的铈、钐共掺杂介孔二氧化钛光催化剂,利用罗丹明B为目标污染物,研究不同掺杂量对光催化性能的影响,对其进行光催化效果评价。采用X射线衍射仪、扫描电子显微镜、X荧光光谱仪(XRF)等手段对其进行表征。结果表明：所制得样品均为锐钛矿相二氧化钛,掺杂后的光催化剂对罗丹明B降解效果有了明显的增强,表明了铈、钐共掺杂的介孔二氧化钛对染料废水的处理能力大大加强。4、经过以上实验遴选出最佳制备工艺路线,并在此工艺路线下进行放大实验。取银川某印染厂的染料废水进行光催化氧化降解,通过测定化学需氧量(COD)来计算降解率对其进行光催化降解效果评定。并采用物理氮气吸附量、扫描电子显微镜等手段对放大样品进行表征。结果表明：在放大工艺下所制得样品对罗丹明B降解效果相对较弱,表明了放大效应对催化剂催化氧化处理染料废水的能力具有很大影响,具体影响因素及各因素影响强度还有待进一步研究。
[Abstract]:The main contents of this paper include: 1. The precursor of this thesis is tetrabutyl titanate, nitric acid as pH regulator, solvent as anhydrous ethanol, inhibitor as acetylacetone, and proper amount of deionized water. Mesoporous TiO2. was prepared by sol-gel method at room temperature using didecaalkyl dimethylammonium bromide as template. The process conditions of preparing stable sol and the main factors affecting the photocatalytic performance of mesoporous Ti02 were summarized through a large number of experiments. The structure and morphology were characterized by X-ray diffraction (XRD) (XRD), physical nitrogen adsorption, scanning electron microscopy (SEM) (SEM), and doping with cerium nitrate hexahydrate as cerium source and samarium nitrate hexahydrate as samarium source. High activity cerium doped mesoporous Ti02, samarium doped mesoporous Ti02 semiconductors were prepared by using sol-gel method to modify rare earth elements. Rhodamine B was used as the target pollutant to study the different doping amount and calcination time. The effect of calcination temperature on photocatalytic performance was evaluated. It was characterized by X-ray diffraction, scanning electron microscope and physical nitrogen adsorption. The results showed that all the samples were anatase phase TIO _ 2, and the degradation effect of rhodamine B was obviously enhanced by doped photocatalyst. The treatment ability of mesoporous TIO _ 2 of samarium to dye wastewater was greatly enhanced. On the basis of above experiments, highly active cerium and samarium co-doped mesoporous TIO _ 2 photocatalysts were prepared by modified sol-gel method. Using Rhodamine B as the target pollutant, the effect of different doping amount on photocatalytic performance was studied, and the photocatalytic effect of Rhodamine B was evaluated. It was characterized by X-ray diffractometer, scanning electron microscope (SEM) and X-fluorescence spectrometer (XRF). The results showed that all the samples were anatase phase TIO _ 2, and the degradation effect of rhodamine B was obviously enhanced by doped photocatalyst. The treatment of dye wastewater with samarium co-doped mesoporous titanium dioxide has been greatly enhanced. The best preparation process has been selected through the above experiments and the amplification experiments have been carried out under this process. The dye wastewater from a printing and dyeing factory in Yinchuan was degraded by photocatalytic oxidation, and the photocatalytic degradation effect was evaluated by determining the chemical oxygen demand (COD) to calculate the degradation rate. The amplified samples were characterized by physical nitrogen adsorption and scanning electron microscopy. The results showed that the degradation effect of Rhodamine B was relatively weak, which indicated that the amplification effect had a great influence on the catalytic oxidation of dye wastewater. The specific influencing factors and the influence intensity of each factor still need to be further studied.
【学位授予单位】：宁夏大学
【学位级别】：硕士
【学位授予年份】：2015
【分类号】：X791;O643.36

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