INVESTIGADORES
CASELLA Monica Laura
artículos
Título:
Hydrogenation of carbonyl compounds using tin-modified platinum-based catalysts prepared via surface organometallic chemistry on metals (SOMC/M)
Autor/es:
GERARDO F. SANTORI, MÓNICA L. CASELLA, OSMAR A. FERRETTI
Revista:
JOURNAL OF MOLECULAR CATALYSIS A-CHEMICAL
Editorial:
Elsevier Science B. V.
Referencias:
Lugar: Amsterdam, The Netherlands; Año: 2002 vol. 186 p. 223 - 239
ISSN:
1381-1169
Resumen:
The catalytic behaviour of some compounds containing C=O and/or C=C bonds has been studied over silica-supported
platinum-based catalysts, modified with tin. Tin was introduced by means of surface organometallic chemistry on metals
(SOMC/M) techniques. The effect of the obtention conditions upon the catalytic performance was evidenced through the
study of three systems having the same Sn/Pt atomic ratio (0.4), but prepared and activated at different temperature.
In the hydrogenation of butyraldehyde and butanone, the adsorption of the 1-(O) type appears as highly favourable, both
from a geometric and electronic point of view. In the benzaldehyde hydrogenation, the increase in the catalytic activity for
PtSn-OM and PtSn-BM systems is quite more important than in the PtSn-OM. system, fundamentally by electronic effects
associated with the presence of ionic tin and of the phenyl group. In the case of the cyclohexene, geometric and electronic, as
well as steric effects lead to a strong reduction of the hydrogenation rate of C=C bond.
These results can be extrapolated to explain the behaviour of the unsaturated ,-aldehydes. The hydrogenation of the C=O
group is promoted and the adsorption modes favourable to the C=C hydrogenation are inhibited by tin. The combination of
both effects leads to the sequence of selectivity to UOL: Pt PtSn-OM. < PtSn-BM < PtSn-OM.1-(O) type appears as highly favourable, both
from a geometric and electronic point of view. In the benzaldehyde hydrogenation, the increase in the catalytic activity for
PtSn-OM and PtSn-BM systems is quite more important than in the PtSn-OM. system, fundamentally by electronic effects
associated with the presence of ionic tin and of the phenyl group. In the case of the cyclohexene, geometric and electronic, as
well as steric effects lead to a strong reduction of the hydrogenation rate of C=C bond.
These results can be extrapolated to explain the behaviour of the unsaturated ,-aldehydes. The hydrogenation of the C=O
group is promoted and the adsorption modes favourable to the C=C hydrogenation are inhibited by tin. The combination of
both effects leads to the sequence of selectivity to UOL: Pt PtSn-OM. < PtSn-BM < PtSn-OM.. system, fundamentally by electronic effects
associated with the presence of ionic tin and of the phenyl group. In the case of the cyclohexene, geometric and electronic, as
well as steric effects lead to a strong reduction of the hydrogenation rate of C=C bond.
These results can be extrapolated to explain the behaviour of the unsaturated ,-aldehydes. The hydrogenation of the C=O
group is promoted and the adsorption modes favourable to the C=C hydrogenation are inhibited by tin. The combination of
both effects leads to the sequence of selectivity to UOL: Pt PtSn-OM. < PtSn-BM < PtSn-OM.-aldehydes. The hydrogenation of the C=O
group is promoted and the adsorption modes favourable to the C=C hydrogenation are inhibited by tin. The combination of
both effects leads to the sequence of selectivity to UOL: Pt PtSn-OM. < PtSn-BM < PtSn-OM.PtSn-OM. < PtSn-BM < PtSn-OM.
