Highly selective separation of propylene/propane mixture on cost-effectively four-carbon linkers based metal-organic frameworks

The separation of propylene and propane is an important but challenging process, primarily achieved through energy-intensive distillation technology in the petrochemical industry. Here, we reported two natural C4 linkers based metal–organic frameworks (MIP-202 and MIP-203) for C3H6/C3H8 separation. Adsorption isotherms and selectivity calculations were performed to study the adsorption performance for C3H6/C3H8 separation. Results show that C3H6/C3H8 uptake ratios (298 K, 100 kPa) for MIP-202 and MIP-203 are 2.34 and 7.4, respectively. C3H6/C3H8 uptake ratio (303 K, 100 kPa) for MIP-203 is up to 50.0. The mechanism for enhanced separation performance of C3H6/C3H8 on MIP-203 at higher temperature (303 K) was revealed by the in situ PXRD characterization. The adsorption selectivities of C3H6/C3H8 on MIP-202 and MIP-203 (298 K, 100 kPa) are 8.8 and 551.4, respectively. The mechanism for the preferential adsorption of C3H6 over C3H8 in MIP-202 and MIP-203 was revealed by the Monte Carlo simulation. The cost of organic ligands for MIP-202 and MIP-203 was lower than that of organic ligands for those top-performance MOFs. Our work sets a new benchmark for C3H6 sorbents with high adsorption selectivities.