过渡金属掺杂SBA的制备工艺研究

摘要SBA-15介孔分子筛具有比表面积大，孔径分布均一且在较宽范围内可调的优势，但其活性位点较少，本文通过过渡金属掺杂改性SBA-15的制备,并在此基础上进行微介孔的合成来增加其酸性活性位点。采用单一模板剂三嵌段共聚物P123，以正硅酸乙酯为硅源，用水热法制备出纯SBA-15，考察了矿化剂KCl不同含量对 SBA-15的影响，通过XRD表征发现当KCl的含量为4.48g时其小角衍射峰强度更高。在此基础上，用水热法分别合成出Al/Si=0.01、0.02的Al/SBA-15和Fe/Si=0.01 的Al-Fe-SBA-15, XRD和SEM分析结果表明合成的分子筛为二维六方相介孔结构。并探索了微介孔结构的合成，以Al-SBA-15为前驱体，加入到对应量的TPAOH和乙醇溶液中，在碱性条件下部分溶解SBA-15，以期合成SBA-15/ZSM-5，实验表明TPAOH 的量对获得SBA-15/ZSM-5并无影响,而不同的温度及晶化时间会影响产物的生成，重结晶的最佳温度在150-180℃之间，最佳的晶化时间以24h为宜。68553

毕业论文关键词：SBA-15 Al-Fe-SBA-15 微介孔分子筛

Title Study on Preparation of SBA Modified with Transition Metal

Abstract

Mesoporous SBA-15 has advantages of large specific surface area, sharp pore size distribution which is adjustable over a wide range, but it has very few active sites. In order to increase its acid active sites, SBA-15 was prepared with transition metal doping, and micro-mesoporous zeolites was also synthesized with attemption. The pure SBA-15 was prepared by hydrothermal method which used a single template tri-block copolymer P123 and TEOS as silica source. The effects of different amounts of mineralizing agent KCl on SBA-15 morphology were investigated. It is showed in XRD that the content of 4.48g KCl is the best for forming ordered mesoporous structure. Based on this amount, the Al-SBA-15(Al/Si= 0.01,0.02) and Al-Fe-SBA-15 (Fe/Si =0.01) was synthesized by hydrothermal method. Characterized by XRD and SEM, the analysis shows that the synthetic zeolites is a two-dimensional hexagonal mesoporous structure. The micro-mesporous zeolites was also researched in this paper, the Al-SBA-15 was added to the mixture of corresponding amount of TPAOH solution and ethanol in order to get partial dissolution of SBA-15 under basic conditions and synthesized SBA-15/ZSM-5. It shows that the amount of TPAOH has no effects on the synthesis of SBA-15/ZSM-5, and different temperature and crystallization time would affect the product. The optimum temperature of recrystallization is between 150-180 ℃, and optimum crystallization time is 24h.

Key words: SBA-15 Al-Fe-SBA-15 micro-mesporous zeolites

1 引言 1

1.1 研究背景及意义 1

1.2 介孔分子筛的分类 2

1.3 SBA 介孔分子筛的合成 2

1.4 SBA 介孔分子筛研究进展 3

1.5 本文主要研究内容 5

2 SBA-15 及 Al、Fe 掺杂 SBA 的制备 6

2.1 实验试剂及仪器 6

2.2 SBA-15 合成方法 6

2.3 Al-SBA-15 及 Al-Fe-SBA-15 的制备 7

2.4 SBA-15 表征手段 7

2.5 结果与讨论 8

3 SBA-15/ZSM-5 的制备 13

3.1 实验试剂及仪器 13

3.2 SBA-15/ZSM-5 的制备 13

3.3 表征手段过渡金属掺杂SBA的制备工艺研究:http://www.youerw.com/huaxue/lunwen_77134.html