ETH Zurich, Department of Chemistry and Applied Biosciences, Wolfgang-Pauli-Strasse 10, 8093 Zurich, Switzerland.
Dalton Trans. 2014 Mar 21;43(11):4514-9. doi: 10.1039/c3dt52972j.
A two-step procedure for the post-synthetic preparation of Lewis acidic Sn-, Zr- and Ti-zeolite β is reported. Dealumination of a commercially available Al-β zeolite leads to the formation of highly siliceous material containing silanol nests, which can be filled in a second step via the solid-state ion-exchange or impregnation of an appropriate metal precursor. Spectroscopic studies indicate that each metal is subsequently coordinated within the zeolite framework, and that little or no bulk oxides are formed--despite the high metal loadings. The synthesised catalysts demonstrate excellent activity for the isomerisation of glyceraldehyde to dihydroxyacetone, a key model reaction for the upgrading of bio-renewable feedstocks, and the epoxidation of bulky olefins.
报道了一种两步法合成路易斯酸性 Sn、Zr 和 Ti-沸石 β 的方法。商业上可用的 Al-β 沸石脱铝后形成含有硅醇窝的高硅材料，这些硅醇窝可在第二步通过适当的金属前体的固-相离子交换或浸渍来填充。光谱研究表明，每种金属随后都在沸石骨架内配位，并且尽管金属负载量很高，但几乎没有或没有形成大块氧化物。所合成的催化剂在甘油醛异构化为二羟丙酮的反应中表现出优异的活性，这是生物可再生原料升级的关键模型反应，同时在大体积烯烃的环氧化反应中也表现出优异的活性。
