A fuel cell system and a method of producing electricity in a fuel cell are described. The fuel cell system includes a reformer for converting an unreformed fuel to produce a reformate fuel gas; and a fuel cell stack adapted to generate electricity using the reformate fuel gas. The unreformed fuel is a solid paraffinic hydrocarbon. Some hydrocarbons include at least about 5 wt. percent olefins; at least about 5 wt. percent n-paraffins; and between about 2 and 50 wt. percent branched paraffins wherein substantially all of the branch groups are monomethyl and wherein the ratio of terminal monomethyl branching to internal monomethyl branching is at least about 1:1.5.
Description
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a schematic illustration of a fuel cell assembly according to an embodiment of the invention.
Claims
1. An apparatus for producing electricity, comprising:
a) a reformer for converting an unreformed fuel to a reformate fuel gas; andb) a fuel cell stack adapted to generate electricity using the reformate fuel gas;wherein the unreformed fuel is a solid paraffin hydrocarbon at ambient temperatures.
2. The apparatus of claim 1, wherein the unreformed fuel comprises at least about 5 wt. percent olefins; at least about 5 wt. percent n-paraffins; and between about 2 and 50 wt. percent branched paraffins wherein substantially all of the branch groups are monomethyl and wherein the ratio of terminal monomethyl branching to internal monomethyl branching is at least about 1:1.5.
3. The fuel cell of claim 2 wherein the ratio of terminal monomethyl branching to internal monomethyl branching is at least about 1:1.
4. The fuel cell of claim 2 wherein the n-paraffins are present in an amount of at least about 20 wt. percent and wherein the ratio of terminal monomethyl branching to internal monomethyl branching is at least about 1.5:1.
5. The fuel cell of claim 2 wherein the n-paraffins are present in an amount of at least about 40 wt. percent and wherein the ratio of terminal monomethyl branching to internal monomethyl is at least about 2:1.
6. The fuel cell of claim 1 wherein the unreformed fuel is a product of a Fischer-Tropsch reaction.
7. The fuel cell of claim 6 wherein the Fischer-Tropsch reaction incorporates feed syngas having 10-60% N2.
8. The fuel cell according to claim 1, further including a carbon monoxide shift unit.
9. The fuel cell according to claim 1, wherein the fuel is a solid at a temperature in the range of about 20° C. to about 50° C.
10. A method of producing electricity in a fuel cell, comprising:
a) converting an unreformed fuel to a reformate fuel gas; andb) electrochemically combining hydrogen derived from said reformate fuel gas with an oxidant without combustion to produce electrical energy;wherein the unreformed fuel is a solid paraffin hydrocarbon at ambient temperatures.
11. The method of claim 10, wherein the unreformed fuel comprises at least about 5 wt. percent olefins; at least about 5 wt. percent n-paraffins; and between about 2 and 50 wt. percent branched paraffins wherein substantially all of the branch groups are monomethyl and wherein the ratio of terminal monomethyl branching to internal monomethyl branching is at least about 1:1.5.
12. The method of claim 11 wherein the ratio of terminal monomethyl branching to internal monomethyl branching is at least about 1:1.
13. The method of claim 11 wherein the n-paraffins are present in an amount of at least about 20 wt. percent and wherein the ratio of terminal monomethyl branching to internal monomethyl branching is at least about 1.5:1.
14. The method of claim 11 wherein the n-paraffins are present in an amount of at least about 40 wt. percent and wherein the ratio of terminal monomethyl branching to internal monomethyl is at least about 2:1.
15. The method of claim 11 wherein the unreformed fuel is a product of a Fischer-Tropsch reaction.
16. The method of claim 15 wherein the Fischer-Tropsch reaction incorporates feed syngas having 10-60% N2.
17. The method according to claim 10, further including a carbon monoxide shift unit.
18. The method according to claim 10, wherein the fuel is a solid at a temperature in the range of about 20° C. to about 50° C.
19. A fuel cell system comprising:
a) a reformer for converting an unreformed fuel to a reformate fuel gas; andb) a fuel cell stack adapted to generate power using the reformate fuel gas;wherein the unreformed fuel comprises at least about 5 wt. percent olefins; at least about 5 wt. percent n-paraffins; and between about 2 and 50 wt. percent branched paraffins wherein substantially all of the branch groups are monomethyl and wherein the ratio of terminal monomethyl branching to internal monomethyl branching is at least about 1:1.5;wherein the unreformed fuel is a solid at a temperature in the range of from about 20° C. to about 50° C.wherein the unreformed fuel is a product of a Fischer-Tropsch reaction that incorporates feed syngas having 10-60% N2.
20. A method of producing electricity in a fuel cell, comprising:
a) providing a solid paraffinic hydrocarbon fuel;b) converting said solid paraffinic hydrocarbon fuel to a liquid, a gas, or a mixture thereof;c) passing said liquid, gas or mixture thereof through a reformer to produce hydrogen; andd) electrochemically combining the hydrogen with an oxidant to produce electrical energy;wherein the unreformed fuel comprises at least about 5 wt. percent olefins; at least about 5 wt. percent n-paraffins; and between about 2 and 50 wt. percent branched paraffins wherein substantially all of the branch groups are monomethyl and wherein the ratio of terminal monomethyl branching to internal monomethyl branching is at least about 1:1.5.