Direct synthesis of hydrocarbons from co-electrolysis solid oxide cell
A method for generating hydrocarbons using a solid oxide electrolysis cell (SOEC) and a Fischer-Tropsch unit in a single microtubular reactor is described. This method can directly synthesize hydrocarbons from carbon dioxide and water. The method integrates high temperature co-electrolysis of H 2 O and CO 2 and low temperature Fischer-Tropsch (F-T) process in a single microtubular reactor by designation of a temperature gradient along the axial length of the microtubular reactor. In practice, methods disclosed herein can provide direct conversion of CO 2 to hydrocarbons for use as feedstock or energy storage.
1. A method for generating hydrocarbons, the method comprising:
heating a first region of a microtubular reactor to a first temperature, the first region of the microtubular reactor including a cathode and an anode in electrical communication with one another and an oxygen ion conducting electrolyte between the cathode and the anode;
flowing a feed stream to the cathode of the first region, the feed stream including H 2 O and CO 2 ; and
collecting a hydrocarbon downstream of a second region of the microtubular reactor, the second region being downstream of the first region and being at a second temperature that is lower than the first temperature, the second region including a Fischer-Tropsch reaction catalyst in fluid communication and downstream of the cathode,
wherein the microtubular reactor defines a continuous space, such that the first region and second region are in contact producing a temperature gradient along the microtubular reactor.
2. The method of claim 1 , the feed stream further comprising H 2 .
3. The method of claim 1 , wherein the first temperature is from about 500° C. to about 1000° C.
4. The method of claim 1 , wherein the second region is from about 200° C. to about 500° C.
5. The method of claim 1 , further comprising applying a voltage potential across the cathode and the anode.
6. The method of claim 1 , further comprising preheating the feed stream.
7. The method of claim 1 , wherein the first temperature and the second temperature are components of a temperature gradient along the microtubular reactor.
8. The method of claim 1 , further comprising flowing a plurality of feed streams to a plurality of microtubular reactors in an array.
9. The method of claim 1 , wherein the hydrocarbon comprises methane.
10. The method of claim 1 , wherein flowing the feed stream comprises:
providing the feed stream to an inlet of the microtubular reactor reacting the feed stream in the first region to form a syngas;
flowing the syngas to the second region; and
reacting the syngas in the second region to form the hydrocarbon.
11. The method of claim 10 , further comprising flowing the hydrocarbon to an outlet of the microtubular reactor, wherein the inlet and the outlet define a continuous space comprising the microtubular reactor.
12. The method of claim 11 , wherein collecting the hydrocarbon comprises: removing an outflow, the outflow comprising material exiting the outlet of the microtubular reactor.
13. The method of claim 11 , wherein the outlet is positioned downstream of the second region.