中孔分子筛的合成 结构表征及催化性能分析.docx

中子L分子筛的合成、结构表征及催化性能研究
摘 要
松油醇酯化、,在工业上有着广泛的应用,它们都是重要的酸催化反应,普遍使用无水AICl3、浓硫酸及浓磷酸等强酸催化弃H,这些催化测存在着用量大、污染环境、腐蚀设备及不能重复使用等缺点。因此,国内外研究者~直在研制新型固体酸催化剂来代替。中孔分子筛()具有均匀而开阔的六方棱柱结构的一维线性孔道,,比表面积超过 700m2/g等特点。对于催化大分子底物的反应具有显著的优势。但是, ,对~些需要强酸催化的反应的活性较低,因此,。本研究采用水热合成法合成出多种中孔分子筛,、 ,并将强酸基团(如BO,”、80。”、A1CI。等)引入其骨架中制得各种强酸性中孔分子筛催化剂。采用XRD、、BET、ESR、 NH;.TPD及Hammett指示剂法对其结构及酸强度进行了表征。结果表明: 所合成的催化剂具有中孔分子筛的特征结构,良好的长程有序性和结晶度;强酸基团已存在于中孔分子筛上,从而产生强酸中心。将所合成的强酸性中孔分子筛首次用于催化松油醇酯化、松节油水合、松节油聚合及2一甲氧基萘的傅一克酰基化反应,筛选出对各模型反应催化效果显著的催化剂,如S0,3-/Zr—MCM一4 I、AICI,/Zr-MCM一4 1及BO a”/Mo·MCM一4 l 等。以催化效果较好的强酸性中孔分子筛作为催化剂,详细考察了催化剂的制备方法、用量以及反应条件等因素对模型反应结果的影响-获得了较好的工艺条件。本工作为强酸性中孔分子筛在相应模型反应中的应用提供了指导依据。
关键词:中孔分子筛:酸催化:松节油;2-甲氧基萘
STUDY ON SYNTHES l S,CHARACTER I ZAT I ON AND CATALYT 1 C ACT I V l T l ES OF MESOPOROUS MOLECULAR S I EVE
ABSTRACT
The esterification of terpineol,the hydration and polymerization of Q-pinene and the Friedel·Crafts acylation are important processes in the fine
炒singchemical reactions are concerned with larger molecule 1
strong acid as traditional catalysts used in the
processes are A1C13,H2S04 and H3P04 which are of some drawbacks such as too large amounts of usage,more environmental problems,serious corrosion tO equipment and non- and more attentions have been paid to using zeolites and solid super acids as catalysts
for the reactions in recent mesoporous molecular sieve MCM-4 I
possesses a hexagonal arrangement of uniformly sized unidimensional mesoporous with diameters which can be systematically varied from to 1 0 Elm,larger surface area of more than 700m‘/g,and should therefore be a potential catalyst for the reactions concerned with larger molecule ,the acidity of MCM-4 1 is poorer and is of low catalytic activity for the reaction using strong acid ,enhancing the acidity of