Designed metal-organic frameworks with potential for multi-component hydrocarbon separation

Petrochemical-related gases, especially light hydrocarbons with 1-8 carbon atoms, are essential indus-trial feedstocks. However, during steam cracking they inevitably coexist with other by-products in multi-component form. The huge amount of energy consumed by the traditional heat-driven distillation separation process encourages the development of energy-efficient adsorption separation technologies. Metal-organic frameworks (MOFs), which are porous sorbents with designable structures, have drawn considerable attention for use in molecular recognition and gas separation. In contrast to the widely stud-ied use of MOFs for binary mixture separation, the separation of multi-component gases is closer to the practical situation in the hydrocarbon industry, but has higher requirements of the MOFs in terms of molecular recognition capability. However, there is a lack of discussion on the use of MOFs for multi -component separation from a structure-function relationship perspective. The present review comprises an extensive summary of current progress in the design of MOFs for multi-component hydrocarbon pro-cesses. Such processes include C2 hydrocarbon purification, C1-C4 gas mixture (except for the mixture containing C2 hydrocarbons only) separation, hexane/C8 isomeric hydrocarbon separation, and multi -component aromatic hydrocarbon separation. The different hydrocarbon selectivity capabilities of MOFs and the corresponding separation sequences in these separation scenarios are also highlighted. We appreciate the separation mechanism at a molecular level and emphasize the importance of MOF des-ignability in achieving satisfactory separation performance. Furthermore, the challenges and perspective insights of multi-component gas separation using MOFs are discussed.(c) 2023 Elsevier B.V. All rights reserved.