Adsorption isotherms and selectivity of CH4/C2H6/C3H8 on MOF-505@5GO
【Abstract】MOF-505@GO composites with different ratios of MOF-505 to graphite oxide were synthesized by solvothermal method. They were characterized by powder X-ray diffractions (PXRD), scanning electron microscopy (SEM), Raman and porosity measurement through nitrogen adsorption. The isotherms of CH4, C2H6 and C3H8 on the MOF-505@GO and MOF-505 were measured separately. The results show that MOF-505@5 GO has the largest pore volumes and BET surface area. The pore volumes and BET surface areas of MOF-505@GO increase as the GO content increases; when the GO content increases to 8% (mass) and 10% (mass), the opposite trend is observed in which the pore volumes and BET surface areas decrease. Accordingly, MOF-505@5 GO exhibits the highest CH4, C2H6 and C3H8 uptake of 0.88 mmol·g−1, 4.81 mmol·g−1 and 5.17 mmol·g−1 at 298 K and 0.1 MPa, having increases of 14.9%, 30.7% and 13.1%, respectively. Moreover, the IAST-predicted C2H6/CH4 selectivity of MOF-505@5 GO is about 40.1 and the C3H8/CH4 selectivity is about 3 056.1. It suggests that MOF-505@5 GO is a promising candidate for separation of C2H6/CH4 and C3H8/CH4.
【Keywords】 MOF-505@GO; methane; ethane; propane; adsorption; binary mixture;
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