The performance of Mo1.0V0.3Te0.23Nb0.23Ox catalyst in the partial oxidation of propane to acrylic acid was improved when the catalyst was modified with an optimal amount of tungsten oxide (WOx), which was present largely in an amorphous phase. The added WO increased the catalyst activity by promoting the dehydration of the oxygenate intermediates in the oxidation process, which eventually accelerated the production of propylene. An increase in the dehydration rates on the W-added catalysts was verified by separate experiments using 1- and 2-propanol as the reactants. The selectivity for the production of acrylic acid was also improved for the W-added catalysts because the dehydration step was promoted to a greater extent than the dehydrogenation step and the number of acidic sites in the catalysts was decreased. The reaction results obtained using the W-added catalysts can be explained based on the reaction paths involved in the propane-oxidation process and on the surface properties of the catalysts analyzed using X-ray diffraction (XRD), infrared (IR) spectroscopy, and the temperature-programmed desorption of ammonia (NH3-TPD). (C) 2010 Elsevier B.V. All rights reserved.