A catalytically induced, self propagating, exothermic dissociation reaction for obtaining oxygen from supercritical carbon dioxide, as follows: (a) heating a mixture of a gas comprising by volume (mole fraction) about 97% carbon dioxide (CO2) and about 3% nitrogen (N2) to about 870 F.; (b) applying to the heated mixture of step (a) a pressure of about 9.4 MPa so that the carbon dioxide becomes a supercritical fluid with s density of about 67 kg/m2; (c) subjecting the pressurized, heated mixture of step (b) to a reduced gravity field of about 0.9 g, and; (d) introducing into the pressurized, heated, low g mixture of step (c) a finely divided powder of a homogenous metal catalyst, thereby catalytically inducing a self propagating, exothermic reaction whereby substantially all of the carbon dioxide present in the mixture dissociates into carbon and oxygen (O2).