Kinetic study of the ethyl lactate synthesis from triose sugars on Sn/Al2O3 catalysts

EDUARDO A. PIGHIN; V. K. DIEZ; J.I. DI COSIMO

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ELSEVIER SCIENCE BV

Lugar: Amsterdam; Año: 2017 vol. 289 p. 29 - 37

0920-5861

The reaction kinetics ofthe liquid-phase synthesis of ethyl lactate from dihydroxyacetone and ethanolwas studied on Sn-promoted alumina catalysts. Yields of »70% were obtained at353K after 7 hours of reaction. The effect of the catalyst Sn loading (1-8wt.%) and reaction temperature (343-373K) on the reactionkinetics was investigated. The reaction is promoted by Lewis acid sitesprovided by surface Sn species. A kinetic model based on a pseudohomogeneousmechanism was postulated to describethe reaction network comprising a sequence of consecutive and parallel reactionsteps. The kinetic rate constant associated to ethyl lactate formationincreases with the number of Lewis acid sites confirming that surface Sn speciesparticipate in the kinetically relevant reaction steps. Catalysts were prepared by impregnation and characterizedby N2 physisorption, X-ray diffraction, UV-vis-DRS, FTIR of pyridineand TPD of NH3