• Title/Summary/Keyword: Br${\o}$nsted acid catalysis

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Acidic Properties of Tungsten Oxide Supported on Zirconia and Catalytic Activities for Acid Catalysis (Zirconia에 담지된 산화텅스텐 촉매의 산 성질과 산 촉매활성)

  • Sohn, Jong Rack;Park, Man Young
    • Applied Chemistry for Engineering
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    • v.10 no.2
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    • pp.247-251
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    • 1999
  • Tungsten oxide supported on zirconia was prepared by drying powdered $Zr(OH)_4$ with ammonium metatungstate aqueous solution, followed by calcining in air at high temperature. Upon the addition of only small amount of tungsten oxide (1 wt % $WO_3$) to $ZrO_2$, both the acidity and acid strength of catalyst increased remarkably, showing the presence of $Br{\ddot{o}}nsted$ and Lewis acid sites on the surface of $WO_3$/$ZrO_2$. The high acid strength and large amount of acid sites on $WO_3$/$ZrO_2$ were due to the presence of the W=O bond nature of complex formed by the interaction between $WO_3$ and $ZrO_2$. The catalyst containing 20 wt % $WO_3$, calcined at 973 K, showed the highest catalytic activity for the 2-propanol dehydration, while the catalyst containing 15 wt % $WO_3$, calcined at 1023 K, exhibited the highest catalytic activity for the cumene dealkylation. For the 2-propanol dehydration the catalytic activities of $WO_3$/$ZrO_2$ catalysts were roughly correlated with their acidities.

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