Adsorption performance of MIL-100(Fe) for separation of olefin–paraffin mixtures

MIL-100(Fe) with a BET surface area of 2558 m2 g−1 was prepared for the separation of olefin–paraffin mixtures. The sample was characterized by X-ray diffraction (XRD), and scanning electron microscope (SEM). Isotherms of C2H4, C2H6, C3H6 and C3H8 were measured with a volumetric method, and the C2H4/C2H6 and C3H6/C3H8 adsorption selectivities of the sample were calculated based on the ideal adsorbed solution theory (IAST). The results showed that (a) MIL-100(Fe) adsorbent achieved a superior C2H4 adsorption capacity of 3.8 mmol g−1 and C3H6 7.5 mmol g−1 at 1 atm and 298 K. (b) The isotherms could be well described by the dual-site Langmuir–Freundlich models. (c) The C2H4/C2H6 and C3H6/C3H8 adsorption selectivity of MIL-100(Fe) at 1 kPa and 298 K were up to 111 and 70, respectively, which can be attributed to the selective π-complexation between olefins and Fe(II) of MIL-100(Fe).