Hidrogenación de aceite de girasol sobre catalizadores de platino: estudio comparativo entre la operación convencional y con propano supercrítico

CRISTIAN M. PIQUERAS; GABRIELA TONETTO,; SUSANA BOTTINI; DANIEL E. DAMIANI

Gramado, Rio Grande do Sul, Brasil

Simposio; XX SICAT – Simpósio Ibero-Americano de Catálise 2006; 2006

The hydrogenation of sunflower oil was studied on TiO2 supported Pt catalysts. The Pt/TiO2 catalyst was modified with K and by high temperature reduction treatment in order to observe their influence on the activity and the cis-isomers selectivity. The catalysts were characterized by atomic absorption, H2 chemisorption, TPR and XRD. The hydrogenation of edible oils at conventional conditions is diffusion controlled. The addition of a supercritical (SC) solvent allows performing the reaction in a homogeneous phase in contact with the solid catalyst. Consequently, catalytic tests using SC propane were also performed. A significant increase was observed in the reaction rate of the homogeneous system. Regarding selectivity, the trans-isomers formation was higher in the reaction under conventional conditions, and the production of saturated compound was favored in the homogeneous operation. The Pt-K/TiO2 catalyst presented a similar TON to Pt/TiO2, although the cis-isomers selectivity increased with the alkali addition. The possible causes of this behavior are discussed.