Adsorption Equilibrium and Kinetics of Nitrogen, Methane and Carbon Dioxide Gases onto ZIF-8, Cu10%/ZIF-8, and Cu30%/ZIF-8

Various ZIFs (ZIF-8, Cu10%/ZIF-8, and Cu30%/ZIF-8) were exploited in the adsorption of N2, CH4, and CO2 gases over a temperature range from 25 to 55 °C. The dual site Langmuir model was used to describe the measured adsorption equilibria. Overall, N2 exhibited the lowest adsorption capacity onto all adsorbents, whereas CO2 gas exhibited the highest adsorbed amount. Among the three adsorbents, the highest adsorption capacities of all gases was onto Cu10%/ZIF-8. The adsorption isosteric heats of different systems were determined. Furthermore, the overall mass transfer coefficients for adsorbing N2, CH4 and CO2 gases on each adsorbent were studied at different temperatures.