摘要:以凹凸棒黏土(Att)为基体,通过溶胶-凝胶浸渍工艺,将一系列不同比例的SnO2-TiO2 (mAtt/m(SnO2-TiO2) = 1; r = nSn/(nSn + nTi)=1, 1/5, 1/6, 1/7, 1/8, 1/9, 1/10, 1/11 , 0 )复合氧化物负载于凹凸棒土表面,制备凹凸棒黏土复合型光触媒剂(Att-SnO2-TiO2)。采用XRD、BET、TEM等分析技术对产物进行了表征。研究结果表明,SnO2-TiO2复合氧化物均匀地负载于凹凸棒土表面;经过复合氧化物负载改性后,凹凸棒土的表面形貌得到明显改善,产物的负载效果好、比表面大。以光触媒降解对硝基苯胺为对象,研究了凹凸棒土复合光触媒的光催化性能。结果表明,凹凸棒土复合光触媒显示出优异的光催化性能,其光催化活性顺序为Att-SnO2-TiO2>Att-TiO2>Att-SnO2>Att;而且比例对凹土复合光触媒剂的性能有明显的影响:在紫外光条件下,当r = 1/8时,Att-SnO2-TiO2显示出优异的光催化性能,90min内对30mg/L对硝基苯胺的降解率达99.8%。且实验证实Att-SnO2-TiO2复合光触媒剂的重复利用率也相当高,在五次回收后对30mg/L对硝基苯胺的降解率达98.7%。54130
毕业论文关键词:凹凸棒,光触媒,溶胶-凝胶浸渍,Att-SnO2-TiO2,对硝基苯胺
Abstract: Photocatalytic removal of Nitroaniline under ultraviolet radiation has been studied using attapulgite (Att) composites, which were synthesized by depositing SnO2-TiO2 hybrid oxides on the surface of Att to form a composite photocatalyst (denoted Att-SnO2-TiO2) using sol-gel dipping process. The obtained products were marked as Att-SnO2-TiO2 and were characterized by X-Ray diffraction (XRD), BET surface area and Transmission electron microscope (TEM) methods. Results showed that Att-SnO2-TiO2 nanocomposite particles with high dispersibility were successfully loaded onto the surface of Att fibers. Correspondingly, the photocatalytic activity of Att was improved significantly by loading Att-SnO2-TiO2.The photoactivity of the composite photocatalyst decreased in the sequence Att -SnO2-TiO2>Att-TiO2>Att- SnO2>Att. In order to achieve the best photocatalyst, Att is always the total quality 50%, but the molar ratio of SnO2 and TiO2 in the Att-SnO2-TiO2 composites was adjusted to give a series proportions r = nSn/(nSn + nTi)=1, 1/5, 1/6, 1/7, 1/8, 1/9, 1/10, 1/11 , 0 . Results indicated that the proportion of SnO2 and TiO2 had a critical effect on the photocatalytic activity. Under ultraviolet light irradiation, the highest degradation rate of 30mg/L p-nitroaniline was 99.8% within 90 min by using Att-SnO2-TiO2 r = 1/8 as photacatalyst. The repeated use of the composite photocatalyst was also confirmed and degradation rate 30mg/L p-nitroaniline maintained 98.7% after 5 times usage.
Key words: Attapulgite, Photocatalyst, Sol - gel dip, Att-SnO2-TiO2, p-nitroaniline
目 录
1 引 言 4
2 实验部分 5
2.1复合光触媒剂的制备 5
2.2 材料表征 5
2.3 材料的光催化性能 6
3 结果与讨论 6
3.1触媒剂的表征 6
3.2 紫外光触媒性能研究 9
3.2.1 触媒剂工作条件的选择 9
3.2.1.1对硝基苯胺浓度的选择 9
3.2.1.2触媒剂的投入量 10
3.2.1.3对硝基苯胺初始溶液的pH值 11
3.2.2 凹凸棒土复合光触媒材料的光触媒性能研究 11
3.2.2.1对硝基苯胺降解产物