Direct synthesis of hydrocarbons from co-electrolysis solid oxide cell
A hydrocarbon generation system that combines a solid oxide electrolysis cell (SOEC) and a Fischer-Tropsch unit in a single microtubular reactor is described. This system can directly synthesize hydrocarbons from carbon dioxide and water. High temperature co-electrolysis of H 2 O and CO 2 and low temperature Fischer-Tropsch (F-T) process are integrated in a single microtubular reactor by designation of a temperature gradient along the axial length of the microtubular reactor. The microtubular reactor can provide direct conversion of CO 2 to hydrocarbons for use as feedstock or energy storage.
1. A hydrocarbon generation system comprising:
a plurality of microtubular reactors in an array, each microtubular reactor including
a first region including a cathode and an anode in electrical communication with one another and an oxygen ion conducting electrolyte between the cathode and the anode,
a second region including a Fischer-Tropsch reaction catalyst in fluid communication and downstream of the cathode; and
a temperature control unit configured to provide the first region at a first temperature that is greater than a second temperature of the second region, wherein each microtubular reactor defines a continuous space, such that the first region and second region are in contact producing a temperature gradient along each microtubular reactor.
2. The hydrocarbon generation system of claim 1 , wherein the outer diameter of the microtubular reactor is about 3 millimeters or less.
3. The hydrocarbon generation system of claim 1 , wherein the cathode comprises nickel-yttria stabilized zirconia, nickel-samaria doped ceria, nickel-gadolinium doped ceria, perovskites having the general formula of La 1-x M1 x M2O 3-δ in which M1 is an alkaline earth element and M2 is a transition metal element, Sr 2 Fe 2-x-y Mo x M y O 6-δ in which M is a transition metal element, and combinations there.
4. The hydrocarbon generation system of claim 1 , wherein the anode comprises lanthanum strontium cobalt iron oxide, strontium-doped lanthanum manganite, strontium-doped lanthanum manganite impregnated with ceria-based catalyst, Sr 2 Fe 2-x-y Mo x M y O 6-δ in which M is a transition metal element, La 1-x M1 x M2O 3-δ in which M1 is an alkaline earth element and M2 is a transition metal element, or combinations thereof.
5. The hydrocarbon generation system of claim 1 , wherein the electrolyte comprises yttria stabilized zirconia, scandia stabilized zirconia, lanthanum gallate-based oxide, doped ceria, or combinations thereof.
6. The hydrocarbon generation system of claim 1 , wherein the Fischer-Tropsch catalyst comprises cobalt, iron, nickel, nickel/platinum alloy, rhodium, ruthenium, palladium, osmium, vanadium, iron, manganese, or combinations thereof.
7. The hydrocarbon generation system of claim 1 , wherein the cathode and the Fischer-Tropsch catalyst are on an inner surface of the microtubular reactor.
8. The hydrocarbon generation system of claim 1 , wherein the cathode and the Fischer-Tropsch catalyst are on an outer surface of the microtubular reactor.
9. The hydrocarbon generation system of claim 1 , wherein the cathode comprises the Fischer Tropsch catalyst.
10. The hydrocarbon generation system of claim 1 , wherein the Fischer Tropsch catalyst comprises Ni and the hydrocarbon comprises methane.
11. The hydrocarbon generation system of claim 10 , wherein methane comprises about 18% to about 23% of the hydrocarbon.