Starting from a basic classification of “hierarchical porosity” this review gives a broad overview of preparation routes towards hierarchically porous all-zeolite and zeolite containing composite materials.

: We present the effect of different combinations of intracrystalline pore systems in hierarchical ZSM‐5 zeolites on their performance as MTO catalysts. We prepared ZSM‐5 zeolites with additional intracrystalline mesoporous, intracrystalline macropores and a novel ZSM‐5 type zeolite with intracrystalline meso and macropores. The catalytic results showed that both used catalysts with mesopores and macropores exhibited three times longer catalyst lifetime compared to a conventional catalyst. However, TGA analysis of the deactivated catalysts showed much larger coke content in the mesoporous catalyst than in the macroporous catalyst. Consequently, macropores predominantly led to reduced coke formation rate while additional mesopores predominantly enhanced the resistance against deactivation by coke. Combining both intracrystalline meso and macropores in one catalyst lead to a tenfold increase in catalyst lifetime. Besides the effect on the catalyst lifetime there was also a strong effect of the additional pore systems on the selectivity of the catalysts. The catalysts containing mesopores showed reduced selectivity to short chain olefins and increased selectivity to larger hydrocarbons in comparison to the catalysts without a mesopores system.

Hierarchical MFI zeolites with differently sized macropores were synthesised and a correlation between the macropore diameter and catalyst lifetime was found.

Campholenic aldehyde is a highly valuable fine chemical that can be obtained by multistep synthesis from monoterpene α-pinene isolated from turpentine oil. Therefore, economical and environmentally benign synthesis of this aldehyde is of great interest. In this study, different titanosilicates were prepared and tested in selective campholenic aldehyde synthesis via isomerization of α-pinene oxide. Titanosilicates with MWW zeolitic structure were synthesized directly and compared with Ti impregnated SBA-15 and commercial titanium silicalite-1. The catalysts were thoroughly characterized and compared in terms of their catalytic activity and selectivity toward the desired aldehyde in isomerization reactions performed either in toluene as a solvent at 70 °C or in N,N-dimethylacetamide at 140 °C. Ti-MWW catalysts showed very high catalytic activity with total conversion of α-pinene oxide. The highest selectivity to campholenic aldehyde, being 96% at the total conversion, was reached over the Ti-MCM-22 catalyst in toluene at 70 °C. This result substantially exceeds any other results published so far in the literature. The great catalytic performance of Ti-MCM-22 was attributed to the combination of the presence of isolated tetrahedrally coordinated Ti species, which act as crucial Lewis acid centres, the absence of undesired Brønsted acidity, and the MWW architecture that facilitates the formation of the target aldehyde.