An afterburner system and method for reducing the CO2 and other pollutants produced by the combustion of a fuel in a combustion chamber while maintaining or increasing the efficiency of said combustion includes feeding a catalyst, preferably lithium and/or boron to the afterburner, or a preconditioning afterburner, along with the exhaust from the combustion chamber. The presence of the catalyst in the after burner results in further reduction of pollutants generated by the combustion in the combustion chamber.