Construction of Fluorinated Propane‐Trap in Metal–Organic Frameworks for Record Polymer‐Grade Propylene Production under High Humidity Conditions

Abstract

Propane/propene (C3H8/C3H6) separation is essential in the petrochemical industry but challenging because of their similar physical and chemical properties. Adsorptive separation with C3H8‐selective porous materials can energy‐efficiently produce high‐purity C3H6, which is highly promising for replacing conventional cryogenic distillation but suffers from unsatisfactory performance. Herein, through the precise incorporation of fluorinated functional groups into the confined pore space, a new fluorinated metal–organic framework (FDMOF‐2) featuring the unique and strong C3H8‐trap is successfully constructed. FDMOF‐2 exhibits an unprecedented C3H8 capture capacity of 140 cm3 cm−3 and excellent C3H8/C3H6 (1:1, v/v) selectivity up to 2.18 (298 K and 1 bar), thus setting new benchmarks for all reported porous materials. Single‐crystal X‐ray diffraction studies reveal that the tailored pore confinement in FDMOF‐2 provides stronger and multiple attractive interactions with C3H8, enabling excellent binding affinities. Breakthrough experiments demonstrate that C3H8 can be directly extracted from various C3H8/C3H6 mixtures with FDMOF‐2, affording an outstanding C3H6 production (501 mmol L−1) with over 99.99% purity. Benefiting from the robust framework and hydrophobic ligands, the separation performance of FDMOF‐2 can be well maintained even under 70% relative humidity conditions.

Machine Learning-Assisted Discovery of Propane-Selective Metal–Organic Frameworks

“…We then calculated the ideal adsorption solution theory (IAST) selectivity based on the C 3 H 8 and C 3 H 6 adsorption isotherms at 298 K. As shown in Figure d, the calculated IAST selectivity for an equimolar mixture of C 3 H 8 /C 3 H 6 can reach up to 2.7 at 298 K and 1 bar, which is consistent with our GCMC simulation, and the value is higher than the reported top-performing MOF adsorbents, such as PCP-IPA (2.48), FDMOF-2 (2.18), NUM-7 (1.7), and HIAM-402 (1.43) . Furthermore, Q st was calculated by fitting single-component gas adsorption isotherms at different temperatures.…”

Rational Design and Reticulation of Infinite qbe Rod Secondary Building Units into Metal–Organic Frameworks through a Global Desymmetrization Approach for Inverse C3H8/C3H6 Separation

“…As shown in Figure 4f, the calculated IAST selectivities are both around 1.7 at very low pressure and steadily drop to 1.37 at 101 kPa, which is comparable to the reported top-performing materials (Figure S29). [46][47][48] We also calculated the IAST selectivity of equivalent C 3 H 8 /C 3 H 6 mixture for the different batch of Cu-ASY, which gives similar value of 1.44 at 101 kPa.…”

Recent advances on metal–organic frameworks for deep purification of olefins

“…54 In the eld of gas separation, MOFs have exhibited superior performance, surpassing most other porous materials. For instance, numerous MOFs have been documented for their efficacy in purifying C 2 H 4 , 55-59 C 3 H 6 , [60][61][62][63][64] xylene, [65][66][67][68][69] as well as capturing carbon dioxide, [70][71][72][73][74] toxic Fig. 1 Timeline of typical MOF materials for the purification of C 2 H 4 and C 3 H 6 .…”