Ag-(Mo-W)/ZrO2 catalysts for the production of propylene oxide: Effect of pH in the preparation of ZrO2 support

  title={Ag-(Mo-W)/ZrO2 catalysts for the production of propylene oxide: Effect of pH in the preparation of ZrO2 support},
  author={Eo Jin Lee and Jong Won Lee and Joongwon Lee and Hyung-Ki Min and Jongheop Yi and In Kyu Song and Do Heui Kim},
  journal={Catalysis Communications},
Abstract Direct oxidation of propylene to propylene oxide was carried out over Ag-(Mo-W)/ZrO2 (pH X) catalysts prepared by changing the pH of Zr precursor solution from 3 to 14 while preparing the ZrO2 support. It was found that the fraction of monoclinic phase and the ratio of acidity to basicity in the catalysts showed a volcano-shaped trend with respect to pH of Zr precursor solution. Such characteristics were well correlated with the selectivity of reaction towards propylene oxide. Ag-(Mo-W… 
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