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表面活性剂在新型介孔分子筛上的应用新进展 总被引:2,自引:0,他引:2
本文对近几年来介孔分子筛的合成研究状况进行了综述,重点介绍了分子筛的合成机理、模板剂的作用、合成新方法等。并展望了新型介孔分子筛的发展趋势,为新材料的开发提供科研依据。 相似文献
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分别采用NaY分子筛、γ-氨丙基三乙氧基硅烷修饰的MCM-41分子筛固载双水杨醛缩乙二胺合钴(Cosahn)配合物,制备了固载型Cosahn/NaY、Cosalen/MCM-41催化剂.采用傅里叶变换红外光谱、热重-差热、X射线衍射、比表面积测定等方法对固载型分子筛催化剂的结构进行表征.结果表明,Cosalen已成功地进入分子筛孔道内.在以氧气为氧源的环己烷氧化反应中,Cosalen/MCM-41催化剂具有较好的活性和对环己醇、环己酮的选择性.该催化反应体系产物中环己基过氧化氢(CHHP)的量很少,表明Cosalen/MCM-41催化剂能加速CHHP的分解.在初始氧气压力0.80 MPa、温度130℃、环己烷用量30 g、Cosalen/MCM-41用量0.30 g、叔丁基过氧化氢0.10 g的条件下反应2 h,环己烷的转化率达到5.96%,醇酮选择性87.03%. 相似文献
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The selective oxidation of hydrocarbons is an important value-enhancing chemical transformation in particular with respect
to fine chemicals and pharmaceuticals production. Enzymatic oxidations operate under mild reaction conditions and produce
little if any waste. However, its industrial use is still limited mainly due to their high cost and the low space time yields.
In the present work, chloroperoxiase from Calariomyces fumago immobilized on the mesoporous molecular sieve SBA-15 was applied for the oxidation of indole to 2-oxoindole using hydrogen
peroxide or tert.-butyl hydroperoxide as oxidants. The performance of the immobilized enzyme was found to be superior to native chloroperoxidase
with respect to maximum conversion and pH range applicable. However, immobilized CPO is still sensitive to high concentrations
of hydrogen peroxide. The use of tert.-buty hydroperoxide is found to avoid this problem, but the reaction rate is significantly reduced. 相似文献
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The selective oxidation of hydrocarbons is an important value-enhancing chemical transformation in particular with respect to fine chemicals and pharmaceuticals production. Enzymatic oxidations operate under mild reaction conditions and produce little if any waste. However, its industrial use is still limited mainly due to their high cost and the low space time yields. In the present work, chloroperoxiase from Calariomyces fumago immobilized on the mesoporous molecular sieve SBA-15 was applied for the oxidation of indole to 2-oxoindole using hydrogen peroxide or tert.-butyl hydroperoxide as oxidants. The performance of the immobilized enzyme was found to be superior to native chloroperoxidase with respect to maximum conversion and pH range applicable. However, immobilized CPO is still sensitive to high concentrations of hydrogen peroxide. The use of tert.-buty hydroperoxide is found to avoid this problem, but the reaction rate is significantly reduced. 相似文献
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综述了水热合成法制备ZSM-12分子筛的影响因素、改性方法及其在催化反应中的应用。众多研究表明,模板剂种类影响ZSM-12分子筛晶粒的尺寸、形状以及酸性,硅铝比和碱度是影响ZSM-12分子筛合成的主要因素,硅凝胶是合成ZSM-12的适宜硅源。Ga、Fe、B、P等适宜的杂原子对ZSM-12进行同晶置换改性可以调节其酸性,酸脱铝改性可以使其总酸量减少、Lewis酸消失。ZSM-12可作为芳烃烷基化、异构化、裂化、重整等诸多反应的催化剂,在反应中表现出良好的催化活性及对目标产物的高选择性,是目前用于择形催化一步法合成2,6-二甲基萘最适宜的分子筛催化剂。 相似文献
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介绍了MCM-41介孔分子筛的优点,主要表现在具有较大的比表面积,孔体积与孔径和可调变等。综述了MCM-41介孔分子筛的合成方法与改性研究现状,阐述了MCM-41介孔分子筛的应用研究进展。 相似文献