Molecular sieve confined catalysts for the catalytic combustion of VOCs: preparation, application and future development

Abstract

Escalating air quality concerns due to rapid industrialization and urbanization have highlighted the significant environmental and health impacts of volatile organic compounds (VOCs). Among various abatement technologies, catalytic combustion is an efficient method to eliminate VOCs. This review examines the latest progress and impending challenges associated with molecular sieve-confined catalysts in the context of VOC catalytic combustion. We begin by discussing the pressing need to address air quality issues caused by VOC emissions. We then delve into the limitations of existing VOC management approaches and highlight the potential of catalytic oxidation technologies, particularly those utilizing non-precious metal catalysts. This review centers on the effectiveness of molecular sieve-confined catalysts, exploring their unique structure–property relationships and their impact on VOC elimination. We have summarized the general properties and compositional designs of molecular sieve-confined metal catalysts with active metal species of three distinct sizes: single atoms, nanoclusters, and nanoparticles. Additionally, we have elaborated on the important effects of molecular sieve-confined catalysts in terms of both physical structural properties and chemical composition. To gain insights into the fundamental reaction mechanisms, we discuss the kinetic models commonly employed in VOC catalytic oxidation reactions. We then delve into the reaction mechanisms and structure–activity relationships of VOC catalytic combustion catalysts, examining factors influencing catalyst activity, stability, and hydrothermal stability. Lastly, we address the practical challenges and future prospects of using molecular sieve-confined catalysts in VOC catalytic combustion, emphasizing the need for further research in detailed mechanism exploration, development of efficient confined catalysts, and synergistic degradation of multi-component VOCs.