MOFs as low temperature adsorbents for carbon dioxide

摘要

Three metal organic framework (MOF) materials (Al(OH)(1.4-bdc), Ni_2(1.4-bdc)2(dabco) and In(OH)(1.4-bdc)) have been prepared, characterized and tested as adsorbents for carbon dioxide. At 25°C the materials adsorb significant amount carbon dioxide, the best adsorbing around 10 wt% CO_2 at 1 atm CO_2 pressure, and up to 60 wt% at 25 atm CO_2. The CO_2 uptake is strongly dependent on the specific surface area and pore volume of the material in question. Under dynamic conditions, using gas mixtures as feed, it is found that the adsorption selectivity reduces in the order H_2O > CO_2 > CH_4 ≈ H_2. The experimental results indicate that MOF based solid adsorbents can have a potential for use in pressure swing adsorption of carbon dioxide at elevated pressures under relatively dry conditions.