Zeolite-encapsulated Cu nanoparticles with enhanced performance for ethanol dehydrogenation

The selective dehydrogenation of ethanol to acetaldehyde is one of the pivotal reactions for biomass valorization, wherein the well-defined and robust Cu-based solid catalysts are highly desired for potential practical application. Herein, ultra-small Cu metal nanoclusters (similar to 1.8 nm), encapsulated inside Silicate-1 (S-1), have been successfully fabricated by an in-situ approach. The as-synthesized Cu@S-1 catalyst shows a near quantitative ethanol conversion, a good acetaldehyde selectivity up to similar to 90 %, and more importantly an excellent stability with no apparent deactivation even after a TOS of 110 h in the continuous dehydrogenation of ethanol to acetaldehyde at 523 K. Comprehensive and thorough characterization studies reveal that the spatial constraint environment of the zeolite could not only efficiently restrict the movements of Cu entities, which thus prevents the metal sintering during catalysis, but also induce a predominant amount of well-retained Cu+ species (up to similar to 70 %) that play an essential role for the enhanced performance. (C) 2022 Elsevier Inc. All rights reserved.

Automated summary

By employing an in-situ synthesis method, ultra-small Cu metal nanoclusters (Cu@S-1) with a diameter of about 1.8 nm, encapsulated inside Silicate-1 (S-1), were successfully fabricated. The Cu@S-1 catalyst exhibits near quantitative ethanol conversion, good acetaldehyde selectivity up to about 90%, and excellent stability in the continuous dehydrogenation of ethanol to acetaldehyde, showing no apparent deactivation even after a TOS of 110 h at 523 K.