Estudio comparativo de catalizadores a base de Pt y Rh soportados para la hidrogenación selectiva de 4-metoxiacetofenona.

VIRGINIA VETERE; EMILIA TÁLAS; SANDOR GÖBÖLÖS; MÓNICA L. CASELLA; OSMAR A. FERRETTI

Gramado, Brasil

Simposio; XX Simposio Iberoamericano de Catálisis; 2006

In this work, they are presented some results of the liquid phase hydrogenation of 4-methoxyacetophenone using Rh/SiO2 and Pt/SiO2 catalysts. The systems arising from their modification with SnBu4 are also analyzed. The addition of tin was carried out employing preparation techniques coming from the so-called Surface Organometallic Chemistry on Metals. The organobimetallic catalysts turned out to be more selective to 1-(4-methoxyphenyl)ethanol than the monometallic ones, for both metals. Platinum based catalysts allowed to obtain selectivities towards the alcohol higher than 90% for the whole interval of conversion analyzed. On the other hand, in the case of the rhodium based systems, the appearance of consecutive hydrogenolysis reactions diminishes the selectivity to the alcohol. The activity of the tin modified catalysts is a function of the Sn/M (M=Pt, Rh) ratio. This way, when Sn/M = 1.0, the selectivity to 1-(4-methoxyphenyl)ethanol reaches near 100%, but the catalytic activity diminishes drastically.