The performance of different Ce-modified PdO/ZrO2 catalysts for methane oxidation in lean mixtures
(5000 ppm of CH4) in presence of external water has been studied in this work. Deactivation experiments
carried out in presence of 20,000 ppm of external water showed that water reversibly inhibits the reaction.
However, it was observed that these catalysts can increase their activity in presence of water at low
temperature (350 C).