The influences of NO addition on the selectivity of the combustion reactions catalyzed by CeO2- and ZrO2-containing oxides were investigated. The addition of catalytic quantities of NO favored a high selectivity toward partial oxidation, even in strongly oxidizing conditions. This was demonstrated in the modification of the selectivity to methane combustion over ZrO2-, Al2O3-, and CeO2-based oxide catalysts by adding the said NO amounts to the feed, significantly increasing the production of CO. The effects were more distinct in the ZrO2 and AL2O3 catalysts than in CeO2-containing ones due to the high-combustion activity of CeO2.
