A series of cobalt-doped vanadium phosphorus oxides (VPO-Co) catalysts, as well as unpromoted sample (VPO) were prepared using classical organic method via VOHPO4 center dot 0.5H(2)O precursor followed by calcinations in n-butane/air environment at 400 degrees C for 24 h. Techniques such as XRD, BET surface area, chemical titration, SEM, TPR and FT-IR were used for characterization of the catalysts. The results showed that promoted and unpromoted VPO catalyst were contained crystalline form of V4+ (vanadyl pyrophosphate, (VO)(2)P2O7) and also a small amount of V5+ (beta-VOPO4 phase). However, Co promoted VPO contained poorer crystallinity compared to the unpromoted catalysts. CoPO4 phase also observed in the VPO-Co series and the intensities of the X-ray lines of CoPO4 increased with the increase of the Co/V molar ratio. In addition, the promotion of Co resulted in larger amount of V5+ species. Co was found to increase the average oxidation number of vanadium from 4.28 to 4.35 due to an addition of V5+ oxidation state from 28% to 35%. Oxidation of benzyl alcohol, for the first time, was studied in the liquid phase over VPO and VPO-Co catalysts, using tert-butylhydroperoxide (TBHP) as an oxidant. The catalytic tests showed that cobalt doping significantly increased the overall activity for the oxidation of benzyl alcohol. At 90 degrees C, the obtained activities were 0.662 and 1.014 g(pro) g(-1) vpo h(-1) over the VPO and VPO-Co (molar ratio Co/V=0.01) catalysts, respectively. The effects of reaction temperature, amount of the catalyst, solvents, and catalyst recycling of VPO-Co in liquid phase were also investigated. (C) 2014 Elsevier B.V. All rights reserved.