Regular Paper
Synthesis of Highly Active Solid Base Catalyst of Calcium Oxide Covered with Thin Layer of Titanium Oxide
2016 Volume 59 Issue 1 Pages 24-30
Details
2016 Volume 59 Issue 1 Pages 24-30
Solid-base catalysts consisting of CaO covered with 5-20 mol% TiO2 (TiO2/CaO) were prepared by deposition of titanium tetraisopropoxide (Ti(OCH(CH3)2)4) on a Ca(OH)2 surface in an ethyl acetate solution, followed by thermal decomposition in air at 773-1073 K for 3 h. The catalyst heated at 773-973 K showed higher activity for the base catalyzed retro-aldol reaction to convert diacetone alcohol (4-hydroxy-4-methyl-2-pentanone) to acetone at 299 K. 10 mol% TiO2/CaO heat-treated at 773 K was the most active catalyst for the retro-aldol reaction among the metal oxide-covered CaO catalysts. The catalyst treated at 1073 K was inactive for the same reaction, as was uncovered CaO. The catalytic activity of TiO2/CaO poisoned by water was recovered by washing with acetone, confirming that TiO2-covered CaO had sufficient stability against H2O. No leaching of Ca2+ into the polar solvent diacetone alcohol was observed in any covered catalyst.
