Trimetallic Oxygen Carriers CuFeMnO₄, CuFeMn₂O₄, and CuFe_0.5Mn_1.5O₄ for Chemical Looping Combustion

Abstract

Several trimetallic ferrites with different ratios of Cu, Fe, and Mn were synthesized by direct decomposition method and tested for chemical looping combustion of methane, synthesis gas, and carbon. For comparison, several bimetallic ferrites were also tested, and NiFe2O4 and CuFe2O4 showed the best performance. During a 55-cycle test, trimetallic CuFeMnO4 showed better overall performance than both NiFe2O4 and CuFe2O4, which had shown the best performance among the bimetallic ferrites for CLC of methane. From all the trimetallic oxygen carriers with different atomic ratios of Cu, Fe, and Mn, CuFeMnO4, CuFeMn2O4, and CuFe0.5Mn1.5O4 showed the best performance for CLC of methane. The oxygen carriers CuFeMnO4, CuFeMn2O4, and CuFe0.5Mn1.5O4, even without a support, showed very stable performance during a 100-cycle TGA test. The CuFeMnO4 oxygen carrier also showed excellent performance during a multicycle CLC test with synthesis gas. CuFeMnO4 is also suitable for CLC of a solid fuel, such as carbon, which showed stable performance during a 10-cycle test.