PNNL

Abstract

It is important to capture carbon dioxide from flue gas which is considered to be the main reason to cause global warming. CO2/N2 separation by novel adsorbents is a promising method to reduce CO2 emission but effect of water and CO2/N2 selectivity is critical to apply the adsorbents into practical applications. A very well known, Metal Organic Framework, NiDOBDC (Ni-MOF-74 or CPO-27-Ni) was synthesized through a solvothermal reaction and the sample (500 to 800 microns) was used in a fixed bed CO2/N2 breakthrough study with and without H2O. The Ni/DOBDC pellet has a high CO2 capacity of 3.74 mol/kg at 0.15 bar and a high CO2/N2 selectivity of 38, which is much higher than those of reported MOFs and zeolites under dry condition. Trace amount of water can impact CO2 adsorption capacity as well as CO2/N2 selectivity for the Ni/DOBDC. However, Ni/DOBDC can retain a significant CO2 capacity and CO2/N2 selectivity at 0.15 bar CO2 with 3% RH water. These results indicate a promising future to use the Ni/DOBDC in CO2 capture from flue gas.