REDUCTION OF CARBON-DIOXIDE TO CARBON WITH ACTIVE CATION EXCESS MAGNETITE

The cation-deficient magnetite(Fe3+deltaO4t, delta < 0 was synthesized by the oxidation of Fe(OH)(2) suspensions at 358 K. The cation-excess magnetite(Fe3+deltaO4, delta > 0) was obtained by flowing H-2 gas through magnetite with cation-deficient composition at 563 K. The stability of Fe(3+delta)0(4) (delta > 0) was investigated at various temperatures and atmosphere. The reactivty of Fe3+deltaO4 of reducing CO2 gas into carbon was studied at 358 K. The results confirm that CO2 was nearly 100% decomposed into carbon, the oxygen in CO2 is transferred in the form of O2- to the cation excess magnetite. The bigger the cation-excess extent of magnetite, the higher the decomposability of CO2, and the more O-2 is produced indirectly.