Hydrophobic paraffin-selective pillared-layer MOFs for olefin purification

Abstract

Adsorption separation of paraffin and olefin is an industrially important process, while developing a highly stable and paraffin-selective adsorbent remains challenging. Herein, a pcu-topology (primitive cubic) robust pillared MOF, termed...

Leveraging Diffusion Kinetics to Reverse Propane/Propylene Adsorption in Zeolitic Imidazolate Framework-8

“…For the definition of porous media permeability, due to significant differences in particle sizes among different ZIF-8 in our work, the Kozeny Carman model , associated with particle size was selected. In this model, κ can be expressed as κ = d p 2 180 ε p 3 ( 1 − ε p ) 2 …”

“…Metal–organic frameworks (MOFs), a class of crystalline hybrid porous materials, have attracted tremendous interest for adsorption-based separations owing to their highly ordered, tunable pore structures. − Several strategies have been employed to separate propane/propylene mixtures using MOFs, with each component’s preferential adsorption achieved by adjusting the framework affinity. − Despite their similar sizes, propylene is slightly smaller along certain directions (Figure S1), enabling kinetic separations through precise pore size control. − Some flexible MOFs display thermoresponsive gate-opening specific to propylene. , Ideal molecular sieving of propylene can be realized in MOFs like KAUST-7 via ligand and metal substitution. , However, tailoring pore architectures and chemistries to match adsorbate properties remains enormously difficult. , …”

Recent progress in metal–organic frameworks for the separation of gaseous hydrocarbons

“…MOFs with OMSs usually interact strongly with C 2 H 4 molecules via π complexation, whereas MOFs with relatively less polar sites, usually, can preferentially adsorb C 2 H 6 over C 2 H 4 . 46–66…”

Active Sites Decorated Nonpolar Pore‐Based MOF for One‐step Acquisition of C2H4 and Recovery of C3H6

“…For C 2 H 6 /C 2 H 4 separation, the development of C 2 H 6 ‐selective MOFs which are capable of preferentially adsorbing C 2 H 6 over C 2 H 4 is more desirable since the C 2 H 4 products can be directly harvested at the outlet, avoiding additional C 2 H 4 desorption step that is indespensably in C 2 H 4 ‐selective MOFs and hence simplifying the separation process greatly [8] . Up to now, there are some recent C 2 H 6 ‐selective MOFs showing both high capacity and selectivity, [9a–c] providing the promising candidates for C 2 H 6 /C 2 H 4 separation, however, for most of developed C 2 H 6 ‐selective MOFs, they still frequently suffer from either low C 2 H 6 capacity because of small pore volumes or poor C 2 H 6 /C 2 H 4 selectivity owing to the difficulty in discriminating C 2 H 4 and C 2 H 6 [1c,7b,9d] . So it remains a constant challenge to solve the “trade‐off” trouble between selectivity and uptake in the design of C 2 H 6 ‐selective MOFs, nevertheless, both are decisive for the final purity and productivity of C 2 H 4 .…”