1. Process for the production of additive for catalysts for fluid catalytic cracking (FCC), characterized in that it comprises the following stages:
1) provide a suspension of zeolite that is selective for light olefins;
2) bring a modifying agent, reagent \u201cX\u201d, in contact with the zeolite that is selective for light olefins;
3) provide a hydrosol of inorganic oxide;
4) mix the hydrosol with the zeolite suspension;
5) dry the suspension in a spray-dryer.
2. Process for the production of additive, characterized in that said additive is any additive based on zeolite that is selective for light olefins that has undergone interaction with the other components by the action of a modifying agent, reagent \u201cX\u201d.
3. Process for the production of additive according to claim 1, characterized in that said zeolite that is selective for light olefins is a zeolite ZSM-5 or a zeolite with a structure equivalent to the structure of zeolite ZSM-5.
4. Process for the production of additive according to claim 1, characterized in that said reagent \u201cX\u201d is an aqueous solution of cations of aluminum or of alkaline-earth metal in the presence of phosphate, preferably an aqueous solution of calcium or magnesium cations in the presence of phosphate.
5. Process for the production of additive according to claim 1, characterized in that the percentage by weight of cations of aluminum or of alkaline-earth metal relative to zeolite, expressed in the form of oxide, is between 0% and 10%, more preferably between 0% and 4%, and most preferably between 0% and 2%.
6. Process for the production of additive according to claim 1, characterized in that the percentage by weight of phosphate relative to zeolite, expressed in the form of phosphorus pentoxide (P2O5), is between 0% and 20%, preferably between 0% and 15%, and more preferably between 0%and 10%.
7. Process for the production of additive according to claim 1, characterized in that the duration of contact between the zeolite that is selective for light olefins and the modifying agent reagent \u201cX\u201d is between 0.25 hours and 10 hours, preferably between 0.5 hours and 4 hours.
8. Process for the production of additive according to claim 1, characterized in that the temperature for mixing the zeolite suspension with the modifying agent reagent \u201cX\u201d is between 10\xb0 C. and 100\xb0 C., preferably between 30\xb0 C. and 80\xb0 C.
9. Process for the production of additive according to claim 1, characterized in that said hydrosol of inorganic oxide contains one or more inorganic oxides.
10. Process for the production of additive according to claim 1, characterized in that said inorganic oxides are a colloidal silica, a synthesized silica, an alumina peptized with nitric acid, a silica-alumina or a mixture combining two or more of these oxides.
11. Additive, characterized in that it is any additive based on zeolite that is selective for light olefins, that has undergone interaction with the other components by the action of a modifying agent reagent \u201cX\u201d.
12. Additive according to claim 11, characterized in that it is produced by a process that comprises the following stages:
1) provide a suspension of zeolite that is selective for light olefins;
2) bring a modifying agent reagent \u201cX\u201d in contact with the zeolite that is selective for light olefins;
3) provide a hydrosol of inorganic oxide;
4) mix the hydrosol with the zeolite suspension;
5) dry the suspension in a spray-dryer.
13. Additive according to claim 11, characterized in that said reagent \u201cX\u201d is an aqueous solution of cations of aluminum or of alkaline-earth metal in the presence of phosphate, preferably an aqueous solution of calcium and magnesium in the presence of phosphate.
14. Additive according to claim 11, characterized in that the percentage by weight of cations of aluminum or of alkaline-earth metal relative to zeolite, expressed in the form of oxide, is between 0% and 10%, more preferably between 0% and 4%, and most preferably between 0% and 2%.
15. Additive according to claim 11, characterized in that the percentage by weight of phosphate relative to zeolite, expressed in the form of phosphorus pentoxide (P2O5), is between 0% and 20%, preferably between 0% and 15%, and more preferably between 0% and 10%.
16. Additive according to claim 11, characterized in that the duration of contact between the zeolite that is selective for light olefins and the modifying agent is between 0.25 hours and 10 hours, preferably between 0.5 hours and 4 hours.
17. Additive according to claim 11, characterized in that the temperature of mixing of the zeolite suspension with the modifying agent is between 10\xb0 C. and 100\xb0 C., preferably between 30\xb0 C. and 80\xb0 C.
18. Additive according to claim 11, characterized in that said zeolite that is selective for light olefins is a zeolite ZSM-5 or a zeolite with a structure equivalent to the structure of zeolite ZSM-5.
19. Additive according to claim 11, characterized in that said hydrosol of inorganic oxide contains one or more inorganic oxides.
20. Additive according to claim 11, characterized in that said inorganic oxides are a colloidal silica, a synthesized silica, an alumina peptized with nitric acid, a silica-alumina or a mixture combining two or more of these oxides.
The claims below are in addition to those above.
All refrences to claim(s) which appear below refer to the numbering after this setence.
1. A diffusion layer for a direct oxidation fuel cell, the fuel cell having a protonically conductive membrane, comprising:
a substrate comprised substantially of carbon, said substrate facilitating the transport of reactants towards a catalyst in intimate contact with said protonically conductive membrane and being coated with an electrically conductive layer that forms a microporous layer on said substrate, said microporous layer having indented channels formed therein, providing preferential flow paths to cause fluids to travel in predetermined directions in the fuel cell and to improve a distribution of the reactant to the catalytic layer.
2. The diffusion layer as defined in claim 1 wherein a catalyst has been applied to at least one side of the membrane of the fuel cell.
3. The diffusion layer as defined in claim 2 wherein said catalyst is applied to both sides of the membrane.
4. The diffusion layer as defined in claim 1 wherein said fluid is substantially water, and said indented channels are formed such that fluid is directed away from the membrane.
5. The diffusion layer as defined in claim 1 wherein said substrate is comprised substantially of carbon cloth.
6. The diffusion layer as defined in claim 1 wherein said substrate is comprised of at least one sheet of carbon paper.
7. The diffusion layer as defined in claim 6 wherein said substrate is comprised of a plurality of sheets of carbon paper.
8. The diffusion layer as defined in claim 1 wherein said electrically conductive layer is substantially hydrophobic.
9. The diffusion layer as defined in claim 8 wherein said electrically conductive layer includes polytetrafluoroethylene and high surface area carbon particles.
10. The diffusion layer as defined in claim 1 wherein said substrate is placed in intimate contact with said protonically conductive membrane.
11. The diffusion layer as defined in claim 1 wherein said indented channels are formed in a spiral pattern.
12. The diffusion layer as defined in claim 1 wherein said indented channels are formed in a lattice pattern.
13. The diffusion layer as defined in claim 1 wherein said indented channels are formed in such a geometric pattern as to draw fluids away from an active electrode area of the membrane.
14. A membrane electrode assembly comprising:
a protonically conductive, electronically non-conductive membrane;
at least one diffusion layer comprising a carbon substrate being coated thereon with an electrically conductive layer that forms a miroporous layer which includes indented channels formed therein, providing preferential flow paths to cause fluids to travel in predetermined directions in the assembly thereby providing a path through which reactants and byproducts may be preferentially transported to direct said reactants and byproducts in predetermined directions in said assembly and to improve a distribution of the reactant to the catalytic layer; and
a catalyst disposed on said membrane and catalyst forming an active area of said assembly.
15. The membrane electrode assembly as defined in claim 14 wherein said catalyst is applied to at least one surface of the membrane.
16. The membrane electrode assembly as defined in claim 15 wherein said catalyst is applied to both surfaces of the membrane.
17. The membrane electrode assembly as defined in claim 14 including a plurality of diffusion layers and wherein at least one said diffusion layer is substantially hydrophobic.
18. The membrane electrode assembly as defined in claim 14 further comprising a membrane to which a catalyst has been applied is disposed between two diffusion layers, at least one of which diffusion layer provides said preferential flow path to direct fluids away from said active area of said assembly.
19. The membrane electrode assembly as defined in claim 14 wherein said membrane is comprised substantially of polyperfluorosulfonic acid.
20. The membrane electrode assembly as defined in claim 14 wherein said membrane is comprised substantially of a cation exchange membrane based on perflouorocarbon polymers with side chain termini of perfluorosulfonic acid groups.
21. The membrane electrode assembly as defined in claim 14 wherein the catalyst applied to at least one surface of the membrane contains platinum.
22. The membrane electrode assembly as defined in claim 21 wherein the catalyst applied to at least one surface of the membrane also contains ruthenium.
23. A direct oxidation fuel cell, comprising:
(A) a membrane electrode assembly, including:
(i) a protonically conductive, electronically non-conductive membrane electrolyte, having an anode face and an opposing cathode face; and
(ii) a catalyst coating disposed on at least one of said anode face and said cathode face, whereby electricity-generating reactions occur upon introduction of fuel solution from an associated fuel source, including anodic conversion of said fuel solution into carbon dioxide, protons and electrons, and cathodic combination of protons, electrons and oxygen from an associated source of oxygen, producing water;
(B) an anodic diffusion layer disposed in intimate contact with said anode face of said membrane electrode assembly which allows said associated fuel mixture to pass through to said anode face as fuel is consumed at said anode, and which also allows anodically-generated CO2 to be transported away from the anode face of the membrane;
(C) a cathodic diffusion layer disposed in intimate contact with said cathode face of said membrane electrode assembly and which allows oxygen to pass through to said cathode face of said membrane electrode assembly, which cathode diffusion layer is comprised of a carbon-containing substrate and a microporous layer having channels formed therein to provide preferential flow paths such that reactants and byproducts in said fuel cell travel in predetermined directions along said channels and to improve a distribution of the reactant to the catalytic layer; and
(D) means for collecting electric current generated in said electricity-generating reactions to provide said electric current to a load.
24. The direct oxidation fuel cell as defined in claim 23 wherein said substrate of said cathode diffusion layer is comprised substantially of carbon cloth.
25. The direct oxidation fuel cell as defined in claim 23 wherein said substrate of said cathode diffusion layer is comprised substantially of carbon paper.
26. A direct oxidation fuel cell system comprising:
(A) a direct oxidation fuel cell including:
(i) a membrane electrode assembly, including:
a.) a protonically conductive, electronically non-conductive membrane electrolyte, having an anode face and an opposing cathode face; and
b.) a catalyst coating disposed on at least one of said anode face and said cathode face, whereby electricity-generating reactions occur upon introduction of fuel solution from an associated fuel source, including anodic conversion of said fuel solution into carbon dioxide, protons and electrons, and cathodic combination of protons, electrons and oxygen from an associated source of oxygen, producing water;
(ii) an anodic diffusion layer disposed in intimate contact with said anode face of said membrane electrode assembly which allows said associated fuel mixture to pass through to said anode face as fuel is consumed at said anode, and also allows anodically-generated CO2 to be transported from the anode face of the membrane;
(iii) a cathodic diffusion layer disposed in intimate contact with said cathode face of said membrane electrode assembly which allows oxygen to pass through to said cathode face of said membrane electrode assembly, and which cathodic diffusion layer is comprised of a carbon-containing substrate and a microporous layer having channels formed therein to provide preferential flow paths such that reactants and byproducts in said fuel cell travel in predetermined directions along said channels and to improve a distribution of the reactant to the catalytic layer; and
(iv) means for collecting electric current generated in said electricity-generating reactions to provide said electric current to a load;
(B) a fuel source;
(C) fuel container and delivery assembly coupled between said fuel source and said direct oxidation fuel cell;
(D) means for removing reactants from the fuel cell;
(E) means for removing byproducts from the membrane electrode assembly; and
(F) an electrical coupling means for connecting the fuel cell with an external device to which is it providing power.
27. The direct oxidation fuel cell system as defined in claim 26 further comprising a coupling between an anode chamber and a cathode chamber of said fuel cell, by which water collected from the cathode face of the membrane is recirculated to the anode chamber of the fuel cell.
28. The direct oxidation fuel cell system as defined in claim 27 further comprising means for mixing water recirculated from said cathode face of said membrane with a fuel substance and means for introducing a fuel and water mixture to the anode face of the membrane electrode assembly.
29. The diffusion layer as defined in claim 1 wherein said microporous layer is substantially comprised of a material that has been allowed to form cracks extending substantially to the edges of the diffusion layer thereby providing a pathway for fluid to be transported away from the active electrode area.
30. The diffusion layer as defined in claim 1 wherein said substrate and microporous layer are substantially comprised of materials selectively chosen such that a fuel substance can pass through said substrate, while carbon dioxide is directed through said preferential flow paths to be released or directed to another portion of said fuel cell.