Syngas conversion to light olefins over silver metallic nanoparticles in bifunctional catalysts

Abstract

The interest in the production of light olefins stems from their pivotal role as building blocks in the chemical industry. In the direct synthesis of light olefins from syngas via the methanol-mediated route over bifunctional catalysts, intermediate hydrogenation of CO to methanol occurs on a metal oxide catalyst, followed by the conversion of methanol to light olefins over a zeolite.This work introduces a novel approach to the synthesis of light olefins from syngas by proposing the use of metallic silver-supported nanoparticles as a key component in the design of bifunctional catalysts. Departing from the traditional use of metal oxide catalysts, we propose the application of metallic silver, which has not previously been explored in this context. Transient kinetic experiments have shown irreversible adsorption of carbon monoxide on zirconia-supported silver catalyst under the reaction conditions. The resulting hybrid zirconia-supported silver catalysts, paired with SAPO-34 zeolite, demonstrate a remarkable enhancement in the selectivity toward light olefins and a significant reduction in methane production compared to conventional zinc-zirconia based systems. This work challenges the traditional approaches to designing catalysts for selectively converting carbon monoxide into light olefins using conventional oxide-zeolite (OX-ZEO) catalysts.