Boron-containing MFI-type zeolites with a hierarchical nanosheet assembly for lipase immobilization.

Hierarchical nanosheet assemblies of boron-containing MFI-type zeolites were successfully synthesized using bifunctional surfactant molecules under static conditions. With the optimized Si/B = 50 in the synthesis gel, a material with high specific surface area (483 m g) and a maximum pore size of 6.5 nm suitable for lipase encapsulation was obtained.

Catalytic test reactions for the evaluation of hierarchical zeolites.

Hierarchical zeolites have received increasing attention in the last decade due to their outstanding catalytic performance. Several types of hierarchical zeolites can be prepared by a large number of different techniques. Hierarchical zeolites combine the intrinsic catalytic properties of conventional zeolites and the facilitated access and transport in the additional meso- or macropore system.

Hierarchy concepts: classification and preparation strategies for zeolite containing materials with hierarchical porosity.

'Hierarchy' is a property which can be attributed to a manifold of different immaterial systems, such as ideas, items and organisations or material ones like biological systems within living organisms or artificial, man-made constructions. The property 'hierarchy' is mainly characterised by a certain ordering of individual elements relative to each other, often in combination with a certain degree of branching. Especially mass-flow related systems in the natural environment feature special hierarchically branched patterns.

Micro/macroporous system: MFI-type zeolite crystals with embedded macropores.

Zeolite crystals with an embedded and interconnected macropore system are prepared by using mesoporous silica particles as a silica source and as a sacrificial macroporogen. These novel hierarchical zeolite crystals are expected to reduce diffusion limitations in all zeolite-catalyzed reactions, especially in the transformation of larger molecules like in the catalytic cracking of polymers and the conversion of biomass.