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Mixed metal oxides have been widely investigated since they have interesting catalytic properties [1]. The presence of a foreign element in the matrix of a pure metal oxide can greatly modified the structural, acid-base and catalytic properties which, in turn, can be modulated by a proper selection of the nature and loading of the foreign element and method of preparation [2]. In this study, TiO2-CeO2 and TiO2-V2O5 mixed oxide were synthesized by sol-gel technique. The physical and chemical properties of materials obtained by this method may vary according to temperature, operating conditions and precursors selected. The mixed xerogels were prepared with a load of 90% (w/w) TiO2 and 10% (w/w) of CeO2 or V2O5, using titanium isopropoxide and hexahydrated cerium nitrate or ammonium metavanadate as precursors, ethanol (99,8 %) as solvent and at pH 4. The gels were dried in air at 50° C for 24 h and calcined in air at temperatures in the range of 200-800 °C for 4 h. Moreover a sample without cerium, 100% (w/w) TiO2, was prepared so as to keep as reference material. The prepared solids were characterized by means of XRD, SEM and TEM. Their textural properties were determined by adsorption-desorption isotherms of N2 at 77 K. The xerogels were tested as catalysts in the liquid phase oxidation at 20 °C of 2,6-dimethylphenol to 2,6-dimethyl-p-benzoquinone (2,6-DMBQ), using ethanol as solvent and aqueous hydrogen peroxide as a clean oxidizing agent. This quinone is a key intermediate for the synthesis of a number of medicines and physiologically active substances [3]. Previously we studied the oxidation of 2,6-dimethylphenol using similar conditions with catalysts based on heteropolyacids [4]. The best performance of TiO2-CeO2 prepared catalysts was achieved by the xerogel calcined at 200 °C; 100 % of conversion and 96 % of yield in 2,6-dimethyl-p-benzoquinone were obtained in this case after 6 hours of reaction. When synthesized TiO2-V2O5 mixed oxide calcined at 200 °C was used as catalyst, 100 % of conversion and 53 % of yield in 2,6-dimethyl-p-benzoquinone were observed after 5 hours of reaction. Other reaction products were detected when catalysts TiO2-V2O5were used. Mixtures of ethanol-water (50:50; 35:65 %(v/v)) were also good solvents to perform this reaction, a conversion of 100% and a yield of 40% were obtained in 4 hours. However in the last conditions also a reaction intermediary, 3,3´,5,5´-tetramethyl-4,4´-diphenoquinone, was identified by a low-resolution mass spectra recorded on GC-MS. This study seeks to contribute to the search of new heterogeneous catalysts to carry out the oxidation of organic compounds in an environmentally sustainable way, low temperature (20 °C), cleaner oxidizing agent (H2O2), and safer solvents. . [1] T. Seiyama, Metal Oxides and Their Catalytic Actions, Kodansha, Tokyo, 1978. [2] K. Tanabe, M. Misono, Y. Ono, H. Hattori, Studies in Surf. Sci. Catal., vol. 51, 1989. [3] I.G. Kolesnik, E.G. Zhizhina, K.I. Matavev, J. Mol. Catal. 153, 147 (2000). [4] P.Villabrille,G.Romanelli,P.Vázquez, C.Cáceres, Appl.Catal.A-Gen. 270,101 (2004)