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Formation of active sites in thermally treated hydrotalcite-based catalysts for acetone aldolization

Identyfikatory
Warianty tytułu
Języki publikacji
EN
Abstrakty
EN
Mg-AI hydrotalcite containing CO3(2-) and NO3(-) as interlayer anions was synthesized according to the coprecipitation method at constant pH (9.0) and temperature (50°C), and then transformed into mixed metal oxides by calcination at 450, 500, 550 or 600°C for 8 h. The as-prepared hydrotalcite-like sample was characterized with respect to its structure (XRD), chemical composition (XRF, elemental analysis) and thermal stability (EGA-MS). Moreover, the textural features of the thermally activated hydrotalcite were examined using low-temperature (77 K) sorption of N2. Changes in the acid-base properties of the precursor calcined at different temperatures were studied by means of temperature-programmed desorptions of NH3 and CO2. It was found that the hydrotalcite-like sample calcined at 450°C, containing a part of non-decomposed interlayer anions, showed a rather low concentration of acidic and basic surface sites. The increase in the calcination temperature caused the removal of the interlayer anions, and an increase in the concentration and strength of the acidic and basic surface centers. The formation of high number of acid/ base surface sites resulted in raising the catalytic activity of the calcined hydrotalcites in the liquid-phase aldol condensation of acetone.
Rocznik
Strony
33--37
Opis fizyczny
Bibliogr. 14 poz., tab., rys.
Twórcy
  • Jagiellonian University, Faculty of Chemistry, ul. Ingardena 3, 30-060 Kraków
  • Jagiellonian University, Faculty of Chemistry, ul. Ingardena 3, 30-060 Kraków
autor
  • Jagiellonian University, Faculty of Chemistry, ul. Ingardena 3, 30-060 Kraków
  • Jagiellonian University, Faculty of Chemistry, ul. Ingardena 3, 30-060 Kraków
autor
  • Jagiellonian University, Faculty of Chemistry, ul. Ingardena 3, 30-060 Kraków
Bibliografia
  • (1) Cavani F., Trifiro F. and Vaccari A., Hydrotalcite-type anionic clays: preparation, properties and applications, Catalysis Today, 1991, 11, 173.
  • (2) Sels B.F., De Vos D.E. and Jacobs P.A., Hydrotalcitelike anionic clays in catalytic organic reactions, Catalysis Reviews, 2001, 43, 443.
  • (3) Sifniades S. and Levy A.B., Acetone, in: Ullmann's Encyclopedia of Industrial Chemistry, 6th edition, Wiley-VCh, 2002.
  • (4) Craven E.C., The alkaline condensation of acetone, Journal of Applied Chemistry, 1963, 13, 71.
  • (5) Kuśtrowski P., Sułkowska D., Pytlowany R. and Dziembaj R., Kinetics of self-condensation of acetone over heterogeneous Ba(OH)2 and Sr(OH)2 catalysts, Reaction Kinetics and Catalysis Letters, 2004, 81, 3.
  • (6) Rao K.K., Gravelle M., Valente J.S. and Figueras F., Activation of Mg-Al hydrotalcite catalysts for aldol condensation reactions, Journal of Catalysis, 1998, 173, 115.
  • (7) Tichit D., Naciri Bennani M., Figueras F., Tessier R. and Kervennal J., Applied Clay Science, 1998, 13, 401.
  • (8) Prinetto F., Tichit D., Teissier R. and Coq B., Mg- and Ni-containing layered double hydroxides as soda substitutes in the aldol condensation of acetone, Catalysis Today, 2000, 55, 103.
  • (9) Roelofs J.C.A.A., van Dillen A.J. and de Jong K.R, Base-catalyzed condensation of citral and acetone at low temperature using modified hydrotalcite catalysts, Catalysis Today, 2000, 60, 297.
  • (10) Dziembaj R., Kuśtrowski P. and Chmielarz L., Syntetyczne hydrotalkity jako prekursory wysoko zdyspergowanych katalizatorów tlenkowych, Przemysł Chemiczny, 2003, 82, 170.
  • (11) Chmielarz L., Kuśtrowski P., Rafalska-Łasocha A., Majda D. and Dziembaj R., Catalytic activity of Co-Mg-Al, Cu-Mg-Al and Cu-Co-Mg-Al mixed oxides derived from hydrotalcites in SCR of NO with ammonia, Applied Catalysis B: Environmental, 2002, 35, 195.
  • (12) Chmielarz L., Kuśtrowski P., Rafalska-Łasocha A. and Dziembaj R., Influence of Cu, Co and Ni cation incorporated in brucite-type layers on thermal behaviour of hydrotalcites and reducibility of the derived mixed oxide systems, Thermochimica Acta, 2003, 395, 225.
  • (13) Shen J., Tu M. and Hu C., Structural and surface acid/base properties of hydrotalcite-derived MgAlO oxides calcined at varying temperatures, Journal of Solid State Chemistry, 1998, 137, 295.
  • (14) Di Cosimo J.I., Apesteguia C.R., Gines M.J.L. and Iglesia E., Structural requirements and reaction pathways in condensation reactions of alcohols on MgyA10x catalysts, Journal of Catalysis, 2000, 190, 261.
Typ dokumentu
Bibliografia
Identyfikator YADDA
bwmeta1.element.baztech-article-BPS2-0030-0047
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