Adsorption separation of propylene/propane by pressure induced flexible porous MOF

The separation of C 3 H 6 from C 3 H 8 represents a significant yet challenging industrial task. Utilizing adsorption separation technology based on porous materials emerges as an energy-saving and cost-effective strategy. In this study, we investigate a flexible porous MOF , HNU-49, as a promising adsorbent for the efficient separation of C 3 H 6 and C 3 H 8 within the temperature range of 288–308 K. Due to its adaptable microporous structure, HNU-49 displays a distinct guest-dependent pressure-induced gate-opening effect, facilitating the effective separation of propylene and propane. Experimental studies, including adsorption isotherms and transient breakthrough experiments, were conducted to evaluate the separation performance of HNU-49, and cyclic experiments were performed to assess its structural stability. At a temperature of 298 K and a pressure of 0.2 bar, HNU-49 exhibits an IAST selectivity of 5.13 for C 3 H 6 /C 3 H 8 . The findings indicate that flexible MOFs with guest-dependent pressure-induced gate-opening effects hold potential applications in selective gas adsorption and separation. Moreover, these stable materials demonstrate good regenerability, making them advantageous for practical applications. • HNU-49 contains deformable ligands, exhibiting pressure-stimulated response. • Flexible HNU-49 is utilized for the efficient separation of C 3 H 6 and C 3 H 8 . • The separation C 3 H 6 /C 3 H 8 of HNU-49 is based on the object-dependent gating effect. • HNU-49 has good repeatability for the separation of C 3 H 6 /C 3 H 8 .