Sn-promoted alumina catalysts with different Sn loadings (1-8 wt.%) were prepared by impregnation and characterized by N-2 physisorption, X-ray diffraction, UV-vis-DRS, FTIR of pyridine and TPD of NH3. Surface Sn species present Lewis acid properties different from those of the alumina support; the number and strength of the surface Lewis centers increase with the Sn loading. These materials exhibit good catalytic performance for conversion of triose sugars, such as dihydroxyacetone, toward ethyl lactates at mild conditions. The catalyst preparation conditions, Sn content and reaction conditions affect the final ethyl lactate yield. Yields of approximate to 70% were obtained at 353 K after 7 h of reaction. Surface Sn species participate in the kinetically relevant reaction steps. (C) 2016 Elsevier B.V. All rights reserved.