alpha-Hydroxyacetone (acetol) which is easily produced from glycerol can be oxidized to other products of industrial interest. In this work the acetol oxidation by homogeneous cheap and green catalytic system FeCl3/H2O2 has been studied. Acetonitrile or water was used as solvent. Acetol (0.5 M) gave acetic acid (0.25 M) and formic acid (0.35 M) as the main products. Some amount of CO2 was also detected. For quantification of the CO2 amount, a novel method has been developed which uses GC-MS for monitoring the signals produced by the CO2 and argon (used as internal standard) present in the headspace of the reaction vessel. The formation of 0.028 M CO2 after 4h under typical conditions was demonstrated. The effects of reactant concentration on the initial reaction rate were studied. The experiments in atmosphere of O-16(2) and O-16(2) + O-18(2) led to the conclusion that molecular oxygen from atmosphere takes part in the reaction and these atoms are incorporated into the products. (C) 2016 Elsevier B.V. All rights reserved.