Surfactant-Templating of Zeolites: From Design to Application

Abstract

Surfactant-templating is one of the most effective and versatile synthetic strategies for the construction of well-defined porous architectures in solids. Though the principles of molecular self-assembly were disclosed in biological systems since long, the use of amphiphiles to generate porous architectures in inorganic matter has merely emerged at the very end of the 20 th century. The present review proposes a voyage from the early developments of surfactanttemplating for designing ordered mesoporous solids to the application of its principles for the generation of hierarchical zeolites. A thorough overview on the various strategies employing supramolecular chemistry to designing mesoporosity in zeolites is presented. The efficiency of the post-synthetic surfactant-templating approach in bridging the gap between zeolites and amorphous mesoporous molecular sieves is depicted through assessing their key properties, such as hydrothermal stability, texture, and acidity. Finally, the impact of hierarchical zeolites in the industry will be highlighted through a review of the catalytic performance of mesostructured zeolites as components of FCC catalysts in various refineries.

Mordenite Nanorods Prepared by an Inexpensive Pyrrolidine‐based Mesoporogen for Alkane Hydroisomerization

“…A direct synthesis in the presence of mesoporogen structure directing agents (SDA) molecules provides a possibility to overcome issues mentioned above . These soft templating procedures offer the opportunity to tune the mesopore system …”

Toolbox of Post‐Synthetic Mordenite Modification Strategies: Impact on Textural, Acidic and Catalytic Properties

“…In order to realize the full potential of mordenite the development of secondary porosity within its structure has been put forward . This approach allows to reduce the diffusion path length (hence increase catalytic activity, selectivity and stability) and at the same time increase the accessibility of bulkier molecules to the active sites . In this quest, a multitude of strategies have been proposed with the aim at achieving mordenite featuring hierarchical porosity .…”

“…[4] This approach allows to reduce the diffusion path length (hence increase catalytic activity, selectivity and stability) and at the same time increase the accessibility of bulkier molecules to the active sites. [5][6][7] In this quest, a multitude of strategies have been proposed with the aim at achieving mordenite featuring hierarchical porosity. [8] Most of these strategies are related to post-synthetic modifications.…”

The success of dual‐functional templating for synthesizing hierarchical analcime zeolite

“…Since then, many researchers have used this kind of new gemini surfactant to synthesize a series of hierarchical molecular sieves. The studies showed that after adding a gemini quaternary ammonium salt cationic surfactant, several attractive features like control of pore size, surface areas (especially areas of mesopores) and interconnection of various pore structures could be improved . So far, gemini quaternary ammonium salt surfactants have mainly been used to produce MFI, BEA and MOR zeolites, rather than analcime (ANA) zeolite.…”