Formation of carbonaceous deposits upon contact of petroleum products with heated metal surface

Summary

• 1. The formation of deposits on a heated metal surface is a consequence of the oxidation of hydrocarbon molecules adsorbed on the surface. Anything that increases the adsorptivity of hydrocarbons on the metal surface (high molecular weights, straight-chain structure, the presence of polar impurities) will also increase the intensity of deposit formation.

• 2. When the surface temperature is increased above a certain limit (T_m), the average residence time of the adsorbed molecules on the surface becomes less than the average time required for diffusion of oxygen molecules from the bulk product to the sorbed molecules. Simultaneously, a decrease is noted in the adsorption activity of the deposits formed on the surface As a result of the action of these factors, the intensity of deposit formation shows an extremal variation with increasing initial surface temperature.