乙二胺丙基功能化的SBA-15介孔分子筛的合成及催化性能

以聚乙二醇-聚丙三醇-聚乙二醇为模板剂、正硅酸乙酯为硅源,在强酸和水热条件下合成了SBA-15介孔分子筛,用氯丙基三甲氧基硅烷和乙二胺对分子筛进行乙二胺丙基功能化。运用X射线衍射、傅里叶红外光谱、N2吸附-脱附等手段对功能化前后的SBA-15介孔分子筛进行了表征。以苯甲醛与乙酰乙酸乙酯的Knoevenagel缩合为模型反应,研究了功能化后的SBA-15介孔分子筛的碱催化性能。实验结果表明,功能化后的SBA-15介孔分子筛对反应具有催化活性,同时反应温度、反应时间、溶剂和活性组分的负载量等条件对SBA-15介孔分子筛的催化活性都有影响。催化活性随着催化剂活性组分负载量的增加而提高,但存在一个最佳值。当达到最佳负载量即硅烷偶联剂与SBA-15介孔分子筛的质量比为5∶1时,以乙醇为溶剂在80℃下反应90m in,苯甲醛的转化率,最大达到29.2%。

Synthesis of Ethylenediamine- Propyl Functionalized SBA -15 Mesoporous Molecular Sieve and Its Catalytic Activity

SBA-15 mesoporous molecular sieves were synthesized by hydrothermal method with polyglycol-polypropanetriol-polyglycol(P123)as template and tetraethyl orthosilicate as silica source,and successively functionalized with 3-chloropropyl-trimethoxysilane and ethylenediamine.SBA-15 mesoporous molecular sieves were characterized by means of XRD,FTIR,N_2 adsorption-desorption before and after functionalization.Activity of catalyst was studied by using knoevenagel condensation of benzaldehyde and acetacetic ester as model reaction.Functionalized SBA-15 was an effective catalyst for this reaction.Activity of the functionalized SBA-15 was affected by reaction temperature,reaction time,type of solvent,and loading amount of basic active component.Activity of functionalized SBA-15 increased with increasing of basic active component loading amount.Under optimal conditions:reaction temperature 80℃,reaction time 90min,ethanol as solvent and(m(chloropropyl-trimethoxysilane)) ∶m(SBA-15)=5 ∶1,conversion of benzaldehyde could reach 29.2%.