Potential of metal-organic frameworks for adsorptive separation of industrially and environmentally relevant liquid mixtures

Abstract

Metal–organic frameworks (MOFs) or porous coordination polymers (PCPs) are defined as crystalline, open, coordination network architectures with potential voids. They have drawn momentous attention across several crossroads of material chemistry since their discovery, owing to an exciting plethora of application-oriented footprints left by this class of supramolecular network solids. The unmatched aspect of tunable coordination nanospace arising from the countless choice of pre-functionalized organic struts pertaining to varying lengths alongside multivariate coordination geometries/oxidation states of the metal nodes, bestows a distinct chemical tailorability facet to this class of porous materials. Amidst the two-decade long attention dedicated to the adsorption–governed purification of gases, the MOF literature has substantially expanded its horizon into the manifestation of industrially relevant liquid mixtures’ adsorptive separation–driven purification. Such chemical separation phenomena categorically encompasses high importance to the manufacturing and processing industry sectors, apart from the fundamental scientific pursuit of discovering novel physicochemical principles. Aimed at the energy-economic preparation of pure industrial feedstocks and their consequent usage as end products, structure–property correlations pursued in the alleys of coordination chemistry has led to major advancements in a number of critical separation frontiers, inclusive of biofuels (alcohol/water), diverse hydrocarbon mixtures, and chiral species. This comprehensive review summarizes the topical developments accrued in the field of MOF based liquid mixtures’ adsorptive separation phenomena, structure–selectivity relationships as well as the associated plausible mechanisms substantiating such behavior.