Carbon Dioxide Reforming of Methane using an Isothermal Redox Membrane Reactor

The continuous production of carbon monoxide (CO) and hydrogen (H 2 ) by dry reforming of methane (CH 4 ) is demonstrated isothermally using a ceramic redox membrane in absence of additional catalysts. The reactor technology realizes the continuous splitting of CO 2 to CO on the inner side of a tubular membrane and the partial oxidation of CH 4 with the lattice oxygen to form syngas on the outer side. La 0.6 Sr 0.4 Co 0.2 Fe 0.8 O 3‐ δ (LSCF) membranes evaluated at 840–1030 °C yielded up to 1.27 μmol CO s −1 from CO 2 , 3.77 μmol H₂ g −1 s −1 from CH 4 , and CO from CH 4 at approximately the same rate as CO from CO 2 . We compute the free energy of the oxygen vacancy formation for La 0.5 Sr 0.5 B 0.5 B′ 0.5 O 3− δ (B, B′=Mn, Fe, Co, Cu) using electronic structure theory to understand how CO 2 reduction limits dry reforming of methane using LSCF and to show how the CO 2 conversion can be increased by using advanced redox materials such as La 0.5 Sr 0.5 MnO 3− δ and La 0.5 Sr 0.5 Mn 0.5 Co 0.5 O 3− δ .