Spectroscopic and catalytic investigation of the NO reactivity on CoAPOs with chabasite-like structure

This contribution reports on a combined spectroscopic and catalytic study of the NO reactivity on cobalt-aluminophosphates with chabasite-related structure, CoAPO-18 and CoAPO-34. FTIR was used to monitor the surface species formed by NO adsorption on both oxidised and reduced catalysts, as well as the NO reactivity towards oxygen. CO molecular probe was also used to evaluate the degree of dispersion of cobalt ions within catalysts with different metal loading. Catalytic test of NO oxidation to NO₂ were performed on properly designed fixed bed micro-reactors and apparatus where NO, NO₂, N₂O and O₂ were continuously monitored. CoAPO-34 catalysts with 0.30 to 0.65 mmol Co/g showed exceptionally high performances which were much superior of the well known Cu-ZSM-5.