Reverse-selective metal–organic framework materials for the efficient separation and purification of light hydrocarbons

Insights into the thermodynamic–kinetic synergistic separation of propyne/propylene in anion pillared cage MOFs with entropy–enthalpy balanced adsorption sites

“…Adsorptive separation based on porous solid adsorbents has been recognized as a promising alternative technology for gas/vapor separation because of its eco-friendly nature and energy efficiency. 4–10 However, due to the great similarity in the molecular size (C 3 H 4 : 4.16 × 4.01 × 6.51 Å 3 , C 3 H 6 : 4.65 × 4.16 × 6.44 Å 3 ) and polarizability (C 3 H 4 : 55.5 × 10 −25 cm 3 , C 3 H 6 : 62.6 × 10 −25 cm 3 ), the adsorptive separation of C 3 H 4 /C 3 H 6 by molecular recognition is still very challenging. 11 Only two examples of zeolites are reported and their C 3 H 4 capacity is relatively low.…”

Tuning the Trade‐Off between Ethane/Ethylene Selectivity and Adsorption Capacity within Isoreticular Microporous Metal−Organic Frameworks by Linker Fine‐Fluorination

“…[17,18] Previous attempts have proved that appropriate pore geometry that match the configuration of C 2 H 6 and the weakly polar surface with well-designed C−H bonds available sites could favor the preferable adsorption of the alkane. [19] Based on this principle, a handful of C 2 H 6 -selective MOFs, e.g., Fe 2 (O 2 )(dobdc)…”

Immobilization of the Polar Group into an Ultramicroporous Metal–Organic Framework Enabling Benchmark Inverse Selective CO2/C2H2 Separation with Record C2H2 Production

“…Extensive endeavors have been devoted to exploring porous solid adsorbents including but not limited to zeolites, activated carbons, metal–organic frameworks (MOFs), hydrogen-bonded organic frameworks (HOFs), covalent–organic frameworks (COFs), and hybrid ultramicroporous materials (HUMs). − Especially, MOFs, also called porous coordination polymers (PCPs), as novel porous organic–inorganic hybrid materials, are constructed from the self-assembly of metal ions or clusters and organic ligands, which become promising adsorbents for gas mixture separation owing to their tunable pore size and pore chemistry. ,, The rational design of the pore shape/size and pore chemistry based on the modular feature of MOFs in reticular chemistry and crystal engineering has enabled some MOF adsorbents to exhibit unprecedented adsorption and separation performance for hydrocarbons, including but not limited to C 2 H 2 /C 2 H 4 , C 2 H 6 /C 2 H 4 , and C 3 H 6 /C 3 H 8 . − However, the almost same kinetic diameter of CO 2 and C 2 H 2 makes it greatly challenging for MOFs to differentiate these gases. Recently, a large number of MOF adsorbents have been reported to be used for CO 2 /C 2 H 2 separation, with almost all of them exhibiting a C 2 H 2 -selective adsorption behavior.…”