(456g) Fine-Tuning Pore Chemistry in Ultra-Microporous Metal-Organic Frameworks for Efficiennt Separation of Light Hydrocarbons

Separation and purification of light hydrocarbons (C1-C4) in petrochemical industry is of significant importance for the production of high-purity valuable feedstocks yet challenging and mainly relies on the energy-intensive and capital-cost processes. Adsorptive separation has been recognized as one of the energy-efficient alternatives by which to revolutionize the current energy-intensive conditions and satisfy the new demands. The key issue is to develop advanced porous materials with high efficiency (high capacity, selectivity, and productivity) for light hydrocarbon separation. Metal–organic frameworks (MOFs) or porous coordination polymers (PCPs) offer prospective solutions to various challenges because their modular nature allows the fine-tuning of their chemical pore environment and in turn the adjustment of host–guest interactions, which play a vital role in sorption processes. Of special interest is the subclass of metal–organic frameworks (MOFs) with pore aperture sizes below 4–7 Å, namely ultra-microporous MOFs, which in contrast to conventional porous materials show great prospects for addressing key separation challenges pertaining to energy and environmental sustainability, specifically materials for carbon capture and separation of light hydrocarbons (alkyne/alkene, olefin/paraffin, olefin/olefin, etc.). How to effectively tune the pore chemistry in confined pore environment to maximum the host-guest interactions is the main issue that should be solved to enhance the separation performances but extremely challenging due to the similar dimensions between gas molecules and pore size. Herein, we provide the efficient strategy to tune the pore chemistry in ultra-microporous MOFs to enhance their light hydrocarbon (C2-C4) separation performances, which set new benchmarks for porous materials in separation.