Rediscovering zeolite mechanochemistry – a pathway beyond current synthesis and modification boundaries

by Gerardo Majano, Lars Borchardt, Sharon Mitchell, Valentin Valtchev, Javier Pérez-Ramírez

http://dx.doi.org/10.1016/j.micromeso.2014.04.006

Highlights

• Mechanochemical treatment versatile tool for zeolite synthesis and modification.
• Scalable, efficient, and mechanistically-distinct to solvent-intensive routes.
• Structural transformations classified according to the energy required.
• Catalytic properties enhanced by mechanochemical activation.
• Rationalization will facilitate the scale up of future zeolite technologies.

Abstract

The search for new and improved methods to synthesize and modify zeolites remains a topic of central academic and industrial relevance. The current reliance on solvent-based methods imposes several drawbacks, including the need for subsequent workup steps and the copious generation of liquid waste. Providing a solvent- and process-efficient, but also a mechanistically-distinct route, mechanochemistry has been postulated as a scalable, one-step approach to overcome these limitations. Uniting essential studies in the field, this perspective explores the potential of mechanochemical methods to contribute to zeolite and zeotype material research. Particular emphasis is given to framework interactions associated with post-synthetic modifications. In addition to the archetypal crystal/particle size reduction, these include the introduction of functionalities by framework activation or ion exchange as well as the moderation of the type, density, and accessibility of active sites by controlled amorphization. The interesting prospects for zeolite catalysis are also discussed. We devise directions to construct a basic understanding of the underlying mechanisms in zeolite-related mechanochemistry, which we expect will broaden its applicability and facilitate the laboratory-to-industry transition.