Abstract:
Using ligands containing methyl and carboxylic acid H
4L self-assemblyed with Zr
4+, the rod-like crystals Zr-MOFs is gotten and characterized by X-ray single crystal diffraction, N
2 adsorption, X-ray powder diffraction to analyze the structure. Adsorption isotherms of CH
4/N
2 are measured by adsorption instrument. The Clausius-Clapeyron equation is used to calculate the adsorption heat of CH
4. The separation coefficient of CH
4/N
2 is calculated from the Ideal Adsorbed Solution Theory(IAST). The results show that Zr-MOFs has good adsorption effect on methane which is about 8.2 cm
3/g at 273 K and 0.1 MPa, and the selectivity factor of CH
4/N
2 is 6.3 which means a better separation result. The isosteric heat of adsorption of CH
4 is about 20 kJ/mol. Compared with other zeolite-like adsorbents, the isosteric heat of adsorption is lower, which means an easier regeneration.