화학공학소재연구정보센터
Applied Catalysis A: General, Vol.320, 122-133, 2007
Ketones from acid condensation using supported CeO2 catalysts: Effect of additives
Metal-doped, supported CeO2/Al2O3 catalysts are effective for the high temperature decarboxylative condensation of carboxylic acids to produce ketones. Representative catalysts were characterized based on H-2 chemisorption, thermogravimetric reduction and coke analysis, and Xray absorption spectroscopies at the Cc L-III-, K and Co K-, and Pd L-III-edges. Supported (on Al2O3) CeO2 (similar to 15-20 wt.%) catalysts selectively catalyze the condensation of isobutyric acid to diisopropyl ketone and that of acetic acid and decanoic acid to methylnonylketone. Catalysts are stable in long-term operation, with periodic regeneration. The optimal temperature range is 470-480 degrees C for the former reaction and 400-420 degrees C for the latter. For the former reaction, doping supported CeO2 catalysts with most transition metals, or with strongly basic or acidic additives, catalyzed a variety of side reactions, but the addition of small amounts of Co that dissolved in CeO2 could increase the yield to desired ketone. For the latter reaction, certain group VIII metals added to CeO2 catalysts in higher concentrations proved beneficial, particularly Co or Pd. (c) 2007 Elsevier B.V. All rights reserved.