Carbon Dioxide Reforming of Methane using an Isothermal Redox Membrane Reactor

Abstract

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 .

Hydrogen‐assisted Carbon Dioxide Thermochemical Reduction on La0.9Ca0.1FeO3−δ Membranes: A Kinetics Study

“…An oxygen flux as high as 1.58 μmol cm −2 s −1 was reported using a 1.0 mm thick Nb 2 O 5 ‐doped SrCo 0.4 Fe 0.5 Zr 0.1 O 3− δ (SCFZ) perovskite membrane with CO 2 feed and CH 4 sweep at 900 °C . Different porous layers with catalysts were coated on both sides (i.e., a mixture of La 0.8 Sr 0.2 MnO 3− δ ‐yttria‐stabilized zirconia–Pd on the CO 2 feed side, and Sr 0.7 Ba 0.3 Fe 0.9 Mo 0.1 O 3− δ ‐Ni on the CH 4 sweep side) to avoid strontium carbonate formation and stabilize the membrane performance for 500 h. Another La 0.6 Sr 0.4 Co 0.2 Fe 0.8 O 3− δ (LSCF) membrane was proposed to decrease carbonate formation tendency and the oxygen flux on this 0.6 mm thick tubular membrane was as high as 0.14 μmol cm −2 s −1 at 1030 °C using CH 4 as the sweep gas . Other type of materials, for instance, dual‐phase materials, were also tested.…”

High Redox Capacity of Al‐Doped La1−xSrxMnO3−δ Perovskites for Splitting CO2 and H2O at Mn‐Enriched Surfaces

“…[51,78,79] In brief, DFT was used to compute the thermochemical stability and the free energy required to form oxygen vacancies, [80,81] Exchange-correlation interactions were treated by the revised Perdew-Burke-Ernzerhof (RPBE) functional. [51,78,79,83] All perovskites were modelled using spin-polarized calculations. [51,78,79,83] All perovskites were modelled using spin-polarized calculations.…”

Effect of Ni Content of Ni/γ‐Al2O3 Catalysts Prepared by the Atomic Layer Deposition Method on CO2 Reforming of Methane

“…Carbon dioxide reforming of methane (CRM), which uses the greenhouse gases as the reactants and produces ideal feedstocks for Fischer‐Tropsch (F‐T) synthesis and methanol synthesis, has gained much attention in recent years. Noble metals, such as Rh and Ru, have good activity and excellent resistance to coke formation . However, the high cost and the rareness of the noble metals force the researchers to switch to some substitutes, e.g., the base metals.…”