The pilot unit POX tests were conducted at temperature till 1200 °C and under nearly ambient pressure (0.11 MPa) with the following materials: Black oil (masut), white oil (base oil Mogul HC 68) and white oil with acetylacetonate (mm%wt.). All these materials were analyzed for kinematic viscosity, density and elemental composition. Special attention was paid to a catalytic effect of nickel concentration in the base oil Mogul HC68 POX on product composition. The selected results indicate neither effect of raw material nor effect of nickel concentration in the feed on the gaseous product composition. The reason consists probably in reaching the chemical equilibrium of the complex reaction system taking place in „flame“ inside the gasification reactor. This conclusion did not support our previous results in case of gasification of biomass / oil mixture.