MCM-22、MCM-49和MCM-56三种分子筛的合成

MWW结构分子筛是一类新型的催化材料，具有独特的10元环孔道和12元环孔穴结构，在多种反应中表现出良好的催化活性。以六亚甲基亚胺作为模板剂，合成了MCM-22、MCM-49和MCM-56三种分子筛，并详细考察了不同硅源、凝胶配比、晶化温度和晶化时间对合成过程的影响。结果表明，凝胶配比和晶化温度对分子筛物相的影响较大。以硅胶粉为硅源，无论在何种晶化时间下都不能得到MCM-56，只能合成出MCM-49。而以碱性硅溶胶为硅源，在较短的晶化时间内就可以得到MCM-56。

Synthesis of MCM-22, MCM-49 and MCM-56 zeolites

MWW zeolites,with their unique framework topology comprising two entirely different micropore systems(two-dimensional 10 MR channel and 12 MR pocket),are novel catalytic material with excellent catalytic activity.MCM-22,MCM-49 and MCM-56 zeolites were synthesized and influences of different factors(silicon source,gel ingredient,crystallization temperature and crystallization time) were investigated.The results indicated that gel ingredient and crystallization temperature had remarkable influence on phase of the zeolites.Only MCM-49 zeolite was synthesized from silica gel powder.No MCM-56 zeolite was synthesized from silica gel powder at any crystallization temperature.MCM-56 zeolite was synthesized from alkaline silica gel powder in short crystallization time.