Fuel cell reactor and a process for direct conversion of a hydrocarbon-containing gas to a higher hydrocarbons product
A fuel cell reactor, preferably a solid oxide fuel cell (SOFC) reactor, for performing direct conversion of a hydrocarbon-containing gas to a higher hydrocarbons product is confined by walls, where reactants are flown in the anode compartments and air is introduced to the cathode compartments, and where oxygen is transferred from one side of the walls to the other side to promote or inhibit a chemical reaction. The process for direct conversion of a hydrocarbon-containing gas to a higher hydrocarbons product takes place in the anode compartment of the reactor, in which produced hydrogen, limiting the conversion to the equilibrium, is reacted in situ with oxygen ions transferred from the cathode compartment to produce steam, thereby removing the equilibrium-limiting hydrogen from the reaction.
1. A process for direct conversion of a hydrocarbon-containing gas to a higher hydrocarbons product in an anode compartment of a fuel cell reactor, in which produced hydrogen, limiting the conversion to the equilibrium, is reacted in situ with oxygen ions transferred from a cathode compartment to produce steam, thereby removing the equilibrium-limiting hydrogen from the reaction.
2. The process according to claim 1 , wherein the hydrocarbon-containing gas is any methane-containing gas, such as natural gas, biogas, synthetic natural gas or shale gas.
3. The process according to claim 1 , wherein the higher hydrocarbons product is a gaseous or a liquid product.
4. The process according to claim 1 , wherein methane is converted to aromatic products according to the equilibrium reaction
n CH 4 ↔n C n H 2n−6 +( n+ 3)H 2 with n= 6,7,8 or 9
where hydrogen is reacted in situ with oxygen ions transferred from the cathode department to produce steam in the fuel cell reactor.
5. The process according to claim 4 , wherein the fuel cell reactor is a solid oxide fuel cell reactor.
6. The process according to claim 1 , wherein a conversion catalyst is coated on an anode surface, loaded in the anode compartment or a combination of both.
7. The process according to claim 2 , wherein the methane-containing gas is cleaned of impurities.
8. The process according to claim 7 , wherein the cleaned gas is further treated in a hydrocarbon treating unit to remove or convert any hydrocarbon species except methane in order to produce a methane-rich feed gas for the fuel cell reactor.
9. The process according to claim 8 , wherein the hydrocarbon treating unit is a pre-reformer operating in an optimized condition to convert higher hydrocarbons with steam to hydrogen and carbon oxides.
10. The process according to claim 9 , wherein unconverted feed gas in the fuel cell reactor is separated and recycled back to the reactor.
11. The process according to claim 10 , wherein a fraction of gas from the fuel cell reactor effluent, which contains hydrogen, is used to clean and treat raw hydrocarbon feed gas.