Article ID | Journal | Published Year | Pages | File Type |
---|---|---|---|---|
41392 | Applied Catalysis A: General | 2011 | 8 Pages |
The amorphous and crystalline mixed 25, 50 and 75 wt.% Al2O3–ZrO2 composites were prepared by means of sol–gel method using aluminum iso-propoxide and zirconyl nitrate precursors. Physicochemical properties were determined using XRD, BET, NH3-TPD, TGA, SEM, and FT-IR spectroscopy. Catalytic activity and selectivity were investigated for the dehydration of 2-octanol and 1,2-diphenyl-2-propanol (DPP). Al75Zr25 composite is more selective than other forms for the conversion of 2-octanol. The selectivity of DPP for 1-alkene formation was increased over Al25Zr75 catalyst. The crystalline 50 wt.% catalyst dehydrated tertiary alcohol (DPP) selectively in the presence of 2-octanol. The amorphous 50 wt.% catalyst dehydrated DPP predominately to 1-alkene isomer. The crystalline catalyst favored the formation of E-2-alkene.
Graphical abstractFigure optionsDownload full-size imageDownload high-quality image (207 K)Download as PowerPoint slideHighlights► Mixed 25, 50 and 75 wt.% Al2O3–ZrO2 composites were prepared by means of sol–gel method. ► Doping ZrO2 with alumina eliminates m-ZrO2 but stabilizes the tetragonal phase. ► Crystalline composite selectively dehydrates DPP over 2-octanol to give E-alkene. ► The amorphous composite produced the least stable kinetically controlled 1-alkene. ► BET surface area at 600 (amorphous) and 1000 °C (crystalline) are 104.2 and 0.3 m2/g.