Pure sunflower oil was hydrotreated (T=633 K, P=5 MPa) aiming the production of a biofuel in the diesel range using beta-Mo2C/Al2O3 as catalyst. The catalyst was synthesized in situ using the temperature-programmed carburization (TPC) methodology with a 20% (v/v) CH4/H-2 gas mixture and 923 K/2 h as synthesis temperature. The catalytic evaluation results indicate that for the employed conditions n-C-18 was the major product. The association of the results of the experiments without (blank) and with catalyst suggests that the overall triglyceride transformation into linear alkanes proceeds in two steps: (i) thermal cracking of the triglyceride forming free fatty acids and (ii) hydrogenation of the double bonds and of the carboxylic group of the free fatty acid forming n-alkanes. No CO and/or CO2 formation were detected implying that decarbonylation and/or decarboxylation routes do not play an important role when molybdenum carbide is used, contrarily to what is commonly observed when supported Co-Mo or Ni-Mo sulfides are employed as catalysts. (C) 2012 Elsevier B.V. All rights reserved.