Highly Selective Gaseous and Liquid-Phase Separation over a Novel Cobalt(II) Metal-Organic Framework

The mild recognition sites of oxygen atoms and phenyl rings from 5-(4-pyridyl)-methoxyl isophthalic acid (5,4-PMIA^2-) moieties and tetrakis(4-pyridyloxymethylene) methane (TPOM) linkers inside the channels of a novel three-dimensional microporous metal-organic framework (MOF) [Co₂(5,4-PMIA)₂(TPOM)_0.5]·xsolvent (1) are presumed to provide pore environments with moderate contacts toward guests, as indicated by grand canonical Monte Carlo simulations, which appear to be beneficial for adsorption and separation applications. As expected, 1 represents one of the rare examples that show both high storage capacity of C₂H_n and good adsorption selectivity of C₂H_n/CH₄ and CO₂/CH₄ under ambient conditions, and yet, it has significantly lower energy consumption for regeneration. In addition, a validated submicro-1-based microsolid-phase extraction (μ-SPE) method for the determination of trace monohydroxylated polycyclic aromatic hydrocarbons in complex human urine was developed with satisfactory sensitivity and good precision by online coupling to liquid chromatography-mass spectrometry, which represents the first example of a mixed-ligand MOF applied as an efficient sorbent for μ-SPE.