Recent advances on metal–organic frameworks for deep purification of olefins

Abstract

The removal of trace impurities, such as alkynes and carbon dioxide, is critically important in the production of high-purity light hydrocarbon olefins, which are essential for a variety of downstream applications. However, hydrocarbon separation presents challenges due to their similarities. Traditional industrial technologies for olefin purification are often associated with high energy consumption, costs, and environmental concerns. As a result, physical adsorption using porous materials without a phase transition of gases has emerged as a promising alternative, offering lower energy requirements and operational simplicity. Metal–organic frameworks (MOFs), with expansive surface areas, significant porosity, and highly customizable pores, exhibit enormous potential for separating light hydrocarbon olefins. This review aims to provide an in-depth summary of the latest advancements in the separation of C₂H₄ and C₃H₆ from trace impurities using MOF materials. We will structure the progress of MOFs in this domain into four distinct sections based on the separation systems involved: (1) C₂H₂/C₂H₄ separation, (2) C₃H₄/C₃H₆ separation, (3) single-step C₂H₄ purification from ternary mixture C₂H₂/CO₂/C₂H₄, and (4) C₃H₆ purification from ternary mixture C₃H₄ (propyne/methylacetylene, MA)/C₃H₄ (propadiene, PD)/C₃H₆. Additionally, the advantages of MOFs in the separation of ethylene and propylene, the innovation in material design, the integration of computer chemistry into reticular chemistry, the underlying separation mechanisms, and the strategies implemented to enhance separation performance will be discussed. Furthermore, this review will delineate the potential challenges encountered in transitioning MOF materials from the realm of academic research to industrial implementation, and summarize the prospects for this rapidly evolving field.