The heterogeneity of adsorption sites and adsorption kinetics of n-hexane on a chromium terephthalate-based metal–organic framework MIL-101(Cr) were studied by gravimetric method and temperature-programmed desorption(TPD) experiments. The MIL-101 crystals were synthesized by microwave irradiation method. The adsorption isotherms and kinetic curves of n-hexane on the MIL-101 were measured. Desorption activation energies of n-hexane from the MIL-101 were estimated by TPD experiments. The results showed that equilibrium amount of n-hexane adsorbed on the MIL-101 was up to 5.62 mmol·g-1at 298 K and 1.6 × 104 Pa, much higher than that of some activated carbons, zeolites and so on. The isotherms of n-hexane on the MIL-101 could be well fitted with Langmuir–Freundlich model. TPD spectra exhibit two types of adsorption sites on the MIL-101 with desorption activation energies of 39.41 and 86.69 kJ·mol-1. It reflects the surface energy heterogeneity on the MIL-101 frameworks for n-hexane adsorption. The diffusion coefficients of n-hexane are in the range of(1.35–2.35) × 10-10cm2·s-1with adsorption activation energy of 16.33 kJ·mol^(-1).
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