This work is related to the subject “Green Chemistry” in particular the role of the catalyst, the useof renewable raw materials and the decrease of hazardous materials.- Four commercial tungstated zirconia provided by Mel-Chemicals.- Two series of tungstated zirconia catalysts prepared by two different methods in a range of(1-20) WO3 wt.% loading- Binary zirconia-based oxides WO3-ZrO2, B2O3-ZrO2, Al2O3-ZrO2, Ga2O3-ZrO2 and In2O3-ZrO2.- Binary oxides WO3-Me2O3 (Me = B, Al, Ga and In) and ternary oxides WO3/(Me2O3-ZrO2)(Me = B, Al, Ga and In) were prepared and studied during my PhD thesis.The catalytic activity of these mixed oxide catalysts was evaluated in cellobiose hydrolysis, fructosedehydration and selective catalytic reduction of NOx. The catalysts were thoroughly characterizedin terms of their acidic and redox properties in order to find correlations between the identifiedactive sites and the catalytic properties. The total conversion is related in general to the acidity ofthe tested catalysts and the most selective catalysts for fructose dehydration and deNOx are thosewith moderate acidity.