A key limitation of much of the work to date is that it has largely been carried out under pure CO2 conditions. For real-world CO2 separations a mixture of gases is always present, not limited to CO2, N2, O2, H2O, CH4, NOX and SOX. A number of initial efforts have been carried out to study mixed gas adsorption, including CO2/H2O mixtures, as well as CO2/CH4 mixtures. The role of H2O should be studied in particular, since various studies have highlighted that H2O can have a significant impact on adsorption thermodynamics. We further note that few studies have investigated CO2 capture materials in the presence of O2, despite O2 often playing an important role in the oxidative degradation of many carbon capture materials. Studies of adsorbent degradation in general have also been lacking.