Abstract: The object of this research is the processes of fuel combustion in the internal combustion engines (ICE), as well as development of the model of adiabatic engine of internal combustion – compressor. The project suggests the experimental research, including materials science, because the optimization of fuel combustion in ICE, along with the help of oxygen separated from the atmosphere, rapidly increases the temperature of combustion and pressure in the cylinders, which requires the new schemes of cooling ad heat-resistant materials. The scientific novelty of this work consists in the fact that besides the increase in energy conversion efficiency of ICE due to the fuel combustion, in the separated from atmosphere oxygen, rapidly increases the efficiency and reduces the emission toxicity, particularly the nitrogen oxides, because the atmosphere nitrogen is excluded from the reaction of fuel combustion and can accumulate for further use, including the fire control.