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The small size of micropores (typically <1 nm) in zeolites causes slow diffusion of reactant and product molecules in and out of the pores and negatively impacts the product selectivity of zeolite based catalysts, for example, fluid catalytic cracking (FCC) catalysts. Size-tailored mesoporosity was introduced into commercial zeolite Y crystals by a simple surfactant-templating post-synthetic mesostructuring process. The resulting mesoporous zeolite Y showed significantly improved product selectivity in both laboratory testing and refinery trials. Advanced characterization techniques such as electron tomography, three-dimensional rotation electron diffraction, and high resolution gas adsorption coupled with hysteresis scanning and density functional theory, unambiguously revealed the intracystalline nature and connectivity of the introduced mesopores. They can be considered as molecular highways that help reactant and product molecules diffuse quickly to and away from the catalytically active sites within the zeolite crystals and, thus, shift the selectivity to favor the production of more of the valuable liquid fuels at reduced yields of coke and unconverted feed. [ABSTRACT FROM AUTHOR]

The isomerization of allylic alcohols to carbonyl compounds by a heterogeneous rhodium complex is reported. Different silica material supports and catalyst/ligand systems were evaluated. The most efficient catalyst in terms of catalytic activity and stability was found to be a cationic rhodium(I) complex with sulfonated phosphine ligands anchored on a mesoporous aluminosilica AlSBA-15. The heterogeneous complex catalyzed the isomerization of a variety of allylic alcohols in excellent yields with very low catalyst loadings (0.5 mol %). The catalyst could be recycled without significant loss of activity or selectivity. The optimized catalyst was characterized by N2 sorption, powder X-ray diffraction, transmission electron microscopy, as well as solution and solid-state nuclear magnetic resonance, and Fourier Transform infrared spectroscopies. [ABSTRACT FROM AUTHOR]

The Zeolite Peacemakers The cover picture shows that a new family of materials, namely mesostructured zeolites, can bridge the gap between conventional (microporous) zeolites and surfactant‐templated (mesoporous) solids. In their Full Paper on p. 3110 ff., J. Garcia‐Martinez, X. Zou, M. Thommes and co‐workers describe how size‐tailored mesoporosity could be introduced into commercial zeolite Y crystals by a simple surfactant‐templating post‐synthetic mesostructuring process. The resulting mesoporous zeolite Y showed significantly improved product selectivity in both laboratory testing and refinery trials. A collaboration of three teams was able to characterize these materials with advanced techniques. [ABSTRACT FROM AUTHOR]