Oriented Design and Engineering of Advanced Metal-Organic Frameworks for Light Hydrocarbon Separations

Abstract

Light olefins, such as ethylene (C2H4) and propylene (C3H6), are essential feedstocks for the production of chemical products. However, the current purification strategy of distillation is energy-intensive and results in high carbon emissions. Adsorptive separation, the selective capture of gas from mixtures by porous materials, is considered a promising alternative or transitional technology. Metal-organic frameworks (MOFs), a kind of porous materials with highly tunable nature, have emerged as an innovative chemistry in the past two decades, offering solutions for separating these small gases. This review highlights recent advances in the design and engineering of advanced MOFs, with a focus on precise control over their pore structure and functionality for the adsorption-based purification of C2H4 and C3H6 from corresponding hydrocarbons with the same carbon number. The importance of rational design in achieving specific functionalities, such as functional sites and molecular sieving in rigid MOFs, local/global dynamics in soft MOFs, is underscored, with examples demonstrating enhanced performance in selective adsorption separation. Additionally, methods and examples of large-scale synthesis of MOFs are briefly described. The goal is to present the state-of-art chemistry and application of MOFs and to offer an outlook towards discovering and designing further new materials.