Modeling Hydrogen Sulfide Adsorption on Chromium-Based MIL-101 Metal Organic Framework

In this work, hydrogen sulfide (H2S) adsorption on a laboratory-synthesized polymeric chromium terephthalate (MIL-101) metal-organic framework was modeled by means of the semiempirical Sips equation in order to obtain parameters of engineering interest. MIL-101 (Cr) samples, synthesized by a simple solvothermal process, were characterized by means of X-ray diffraction, field-emission scanning electron microscopy, microporosimetric analysis and Fourier transform infrared spectroscopy. High crystallinity, very high specific surface area and pore volume were found. H2S adsorption isotherms on MIL-101 (Cr) were evaluated at four different temperatures (273, 298, 323 and 348 K) at pressures of up to approximately 0.1 kPa by means of a gravimetric technique using a McBain-type balance. The modeling and experimental results showed that MIL-101 (Cr) had a high H2S adsorption capacity at near-ambient temperature and low heat release during adsorption, suggesting a potential use of the selected metal-organic framework for fixed-bed adsorption operations.