The oxidation of glycerol into lactic acid using activated carbon with Pd or Pt as heterogeneous catalysts was study. Several reaction parameters were evaluated: catalyst loading, catalyst weight, NaOH/glycerol molar ratio, temperature and reaction time. The textural and structural properties of the carbon supported catalysts (fresh and spent) were evaluated by N-2 adsorption-desorption isotherms at -196 degrees C, XRD, SEM, EDX, TEM and XPS. It was possible to achieve a glycerol conversion of about 99% with selectivity to lactic acid of 68% and 74% using 10% Pd/C and 5% Pt/C as catalysts, respectively, at 230 degrees C of reaction temperature. Moreover, Pd/C and Pt/C catalysts were used in five reaction cycles without significant loss of activity, highlighting the great stability of the prepared catalysts. (C) 2016 Elsevier B.V. All rights reserved.