Catalytic effect of heavy metal oxides on crude oil combustion

Differential scanning calorimetry (DSC) and thermogravimetric analysis (TGA) were applied to crude oil combustion in the presence and absence of metal oxides. It was found that the effect of titanium oxide was similar to that of silica and alumina. Vanadium, nickel, and ferric oxides behaved similarly in enhancing the endothermic reactions. In the presence of a large surface area such as with silica, the surface reactions are predominant and unaffected by the small amount of metal oxide present. Kinetic analysis of the DSC curves revealed that the activation energies and the frequency factors of the hydrocarbon and the coke combustion reactions, estimated for all the metal oxide additives including silica and alumina, followed the same normal compensation trend. The crude oil mixture of 90% ferric oxide was the only exception to this trend.