CoCuAlOx mixed oxides for the CO2 purification from oxycombustion process exhaust feed
Résumé
To produce CO2 rich effluents, oxyfuel combustion is a promising technology. Nevertheless, storage as well as valorization steps require the removal CO and NOx produced during combustion process to reach a CO2 as purest as possible. In view of development of transition metal-based catalyst for this application, CoCuAlOx mixed oxide derived from hydrotalcite like preparation way were used as catalyst for NO-CO abatement in a gas stream
similar to those obtained in oxyfuel combustion. Materials characterization was explored by several techniques (XRD, Surface area analysis, TPR, HAADF-STEM coupled with EDX, in-situ XPS) that show good catalyst homogeneity and copper surface species modification. The best catalytic performances for the NO-CO abatement are obtained with the ratio Co/Cu = 2 mixed oxide catalyst. The impact of water was also investigated and following trends were obtained: (i) a shift towards CO oxidation higher temperature; (ii) a decrease of NO reduction yield due to copper surface species modification.