Corma Avelino, Rey Fernando, Valencia Susana, Jordá Jose L, Rius Jordi
Instituto de Tecnología Química, (UPV-CSIC), Universidad Politécnica de Valencia, Avda. de los Naranjos s/n, 46022 Valencia, Spain.
Nat Mater. 2003 Jul;2(7):493-7. doi: 10.1038/nmat921.
One of the major goals in catalysis is to improve the capabilities of microporous materials. This can be accomplished by synthesizing new zeolites with controlled pore architectures. In particular, zeolites containing channels of different sizes in the same structure are desirable. Here, we report a zeolite containing fully interconnected 8-, 10- and 12-membered-ring pores, synthesized by combining the structure-directing effect of the organic 1,5-bis-(methylpyrrolidinium)-pentane and the framework isomorphic substitution of germanium for silicon. Analysis of the crystal structure determined by direct methods from synchrotron powder diffraction data reveals 16 independent tetrahedrally coordinated atoms. This thermally and hydrothermally stable zeolite structure, when synthesized in its acidic form by incorporating aluminium in the framework, presents unique catalytic shape-selectivity effects derived from its particular pore topology.
催化领域的主要目标之一是提高微孔材料的性能。这可以通过合成具有可控孔结构的新型沸石来实现。特别是,在同一结构中包含不同尺寸通道的沸石是理想的。在此,我们报道了一种沸石,它含有完全相互连接的8元、10元和12元环孔,是通过结合有机1,5-双(甲基吡咯烷鎓)戊烷的结构导向作用和锗对硅的骨架同晶取代而合成的。通过直接法从同步辐射粉末衍射数据确定的晶体结构分析揭示了16个独立的四面体配位原子。这种热稳定和水热稳定的沸石结构,当通过在骨架中引入铝以酸性形式合成时,因其特殊的孔拓扑结构而呈现出独特的催化形状选择性效应。