the present invention relates to a process for preparing hydroxylated aromatics by using hydrogen and oxygen and more particularly , to a process for preparing hydroxylated aromatics by using hydrogen and oxygen with a two - component heterogeneous catalyst . one component consists of porous catalyst containing one of group viii b transition metals such as pd , pt , au and cu , and hydrogen transfer organic compounds such as anthraquinone . the other component consists of a catalyst containing a transition metal selected from ti , v , and sn with tetrahedral coordination geometry . the main advantages of this new catalytic system are to 1 ) overcome the drawbacks of liquid phase oxidation using conventional homogeneous catalysts , 2 ) avoid use of expensive hydrogen peroxide as an oxidant , and 3 ) improve the selectivity of the reaction .