Cu-Mn-Ce ternary oxide catalyst coupled with KOH sorbent for air pollution control in confined space

For air pollution control in confined space such as submarine and spacecraft, copper-manganese-cerium ternary oxide catalysts coupled with KOH sorbent were synthesized through the wet impregnation method, solid-state impregnation method A and B, and wet/solid-state impregnation method. The samples were tested for CO and CO₂ removal dynamically and isothermally from 30 °C to 150 °C using two fixed bed reactors, and then characterized by XRD, nitrogen adsorption and desorption, and FE-SEM/EDS. The results showed that all the coupled CuMnCe/KOHs were able to catalyze CO and capture the produced CO₂ in situ. While the coupling treatments affected the CO oxidation and CO₂ absorption performance of the samples significantly and differently. Among all samples, CuMnCe/KOH-WSI with the large KOH bulk phase exhibited the outstanding CO catalytic activity and CO₂ sorption efficiency, higher than the uncoupled CuMnCe/KOH. While for CuMnCe/KOH-WI and CuMnCe/KOH-SI-I samples demonstrating high-dispersed KOH species in the catalyst, the addition of the sorbent could inhibit the catalyst activity due to the occupation of the surface site and pore structure. Furtherly, the effect of the temperature was varied for CO conversion and CO₂ capture performances of the sample, while they achieved an optimization balance at 150 °C for CuMnCe/KOH-WSI.