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 m2/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 °C. Pd supported on the Na 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.
Bibliographical noteFunding Information:
The financial support of this work by FONDECYT Project 8000015 and FONDAP Project 119800002 is gratefully acknowledged. We also acknowledge the donation of the commercial zirconium hydroxide from MEL.
- High area zirconia
- Pd supported catalyst