Methane oxidation on Pd supported on high area zirconia catalysts

Abstract

The results presented in this work clearly show that zirconia synthesized by precipitation of zirconyl chloride with NaOH leads to a zirconia with high surface area (224 m(2)/g), which is relatively stable after high temperature exposure. Pd supported on this high surface area zirconia exhibit higher turnover frequency for methane combustion than when supported on zirconia obtained from zirconyl chloride precipitated with ammonium hydroxide. We also found that when the commercial zirconium hydroxide is subjected to a NaOH reflux treatment, we obtained a zirconia of high and stable surface area (157 m(2)/g) even after heating it at 700 degrees C. Pd supported on the T a treated commercially derived support shows the highest dispersion and the highest intrinsic activity than on any of the other preparations studied. The results presented in this paper open up a new venue for obtaining high surface area zirconia using the commercially available hydroxide.

This work shows that it is possible to stabilize zirconia using a Na treatment and also obtain high catalytic activity for methane oxidation on Pd stabilized on such support. Kinetic results and the corresponding mechanistic interpretation and the IR results support that the effect is consistent with increasing water support interactions which in term affect the reaction kinetics.