摘要:
A self-regulating gas generator that, in response to gas demand, supplies and automatically adjusts the amount of gas (e.g., hydrogen or oxygen) catalytically generated in a chemical supply chamber from an appropriate chemical supply, such as a chemical solution, gas dissolved in liquid, or mixture. In some embodiments, the gas generator may employ a piston, rotating rod, or other element(s) to expose the chemical supply to the catalyst in controlled amounts. In another embodiment, the self-regulating gas generator uses bang-bang control, with the element(s) exposing a catalyst, contained within the chemical supply chamber, to the chemical supply in ON and OFF states according to a self-adjusting duty cycle, thereby generating and outputting the gas in an orientation-independent manner. The gas generator may be used to provide gas for various gas consuming devices, such as a fuel cell, torch, or oxygen respiratory devices.
摘要:
A proton exchange membrane (PEM) with an ion exchange capacity of not less than 1 molar equivalent per kilogram and less than 20% water swelling is provided. The PEM includes a polymer having a polyphosphazene backbone with a polyaromatic functional group linked to the polyphosphazene as a polyaromatic side chain, a non-polyaromatic functional group linked to the polyphosphazene as a non-polyaromatic side chain, and an acidic functional group linked to the non-polyaromatic side chain. The polyaromatic functional group linked to the polyphosphazene provides for increased thermal and chemical stability, excellent ionic conductivities and low water swelling. The mole fraction of polyaromatic functional groups linked to the polyphosphazene backbone is between 0.05 and 0.60.
摘要:
A self-regulating gas generator that, in response to gas demand, supplies and automatically adjusts the amount of gas (e.g., hydrogen or oxygen) catalytically generated in a chemical supply chamber from an appropriate chemical supply, such as a chemical solution, gas dissolved in liquid, or mixture. In some embodiments, the gas generator may employ a piston, rotating rod, or other element(s) to expose the chemical supply to the catalyst in controlled amounts. In another embodiment, the self-regulating gas generator uses bang-bang control, with the element(s) exposing a catalyst, contained within the chemical supply chamber, to the chemical supply in ON and OFF states according to a self-adjusting duty cycle, thereby generating and outputting the gas in an orientation-independent manner. The gas generator may be used to provide gas for various gas consuming devices, such as a fuel cell, torch, or oxygen respiratory devices.
摘要:
In one aspect, a method of forming an electrode for an electrochemical device is disclosed. In one embodiment, the method includes the steps of mixing at least a first amount of a catalyst and a second amount of an ionomer or uncharged polymer to form a solution and delivering the solution into a metallic needle having a needle tip. The method further includes the steps of applying a voltage between the needle tip and a collector substrate positioned at a distance from the needle tip, and extruding the solution from the needle tip at a flow rate such as to generate electrospun fibers and deposit the generated fibers on the collector substrate to form a mat with a porous network of fibers. Each fiber in the porous network of the mat has distributed particles of the catalyst. The method also includes the step of pressing the mat onto a membrane.
摘要:
A self-regulating gas generator that, in response to gas demand, supplies and automatically adjusts the amount of gas (e.g., hydrogen or oxygen) catalytically generated in a chemical supply chamber from an appropriate chemical supply, such as a chemical solution, gas dissolved in liquid, or mixture. In some embodiments, the gas generator may employ a piston, rotating rod, or other element(s) to expose the chemical supply to the catalyst in controlled amounts. In another embodiment, the self-regulating gas generator uses bang-bang control, with the element(s) exposing a catalyst, contained within the chemical supply chamber, to the chemical supply in ON and OFF states according to a self-adjusting duty cycle, thereby generating and outputting the gas in an orientation-independent manner. The gas generator may be used to provide gas for various gas consuming devices, such as a fuel cell, torch, or oxygen respiratory devices.
摘要:
A proton exchange membrane (PEM) with an ion exchange capacity of not less than 1 molar equivalent per kilogram and less than 20% water swelling is provided. The PEM includes a polymer having a polyphosphazene backbone with a polyaromatic functional group linked to the polyphosphazene as a polyaromatic side chain, a non-polyaromatic functional group linked to the polyphosphazene as a non-polyaromatic side chain, and an acidic functional group linked to the non-polyaromatic side chain. The polyaromatic functional group linked to the polyphosphazene provides for increased thermal and chemical stability, excellent ionic conductivities and low water swelling. The mole fraction of polyaromatic functional groups linked to the polyphosphazene backbone is between 0.05 and 0.60.
摘要:
The present invention provides a method for fabricating an asymmetric fluoropolymer membrane comprised of a fluoropolymer material, the membrane having a first surface comprised of a dense layer of the fluoropolymer material, and an opposite second surface comprised of a porous layer of the fluoropolymer material, comprising the steps of:(a) dissolving a fluoropolymer material in a solvent to form a solution;(b) depositing the solution on a casting surface; and(c) removing the solvent from the solution, thereby precipitating the membrane therefrom.The present invention also provides asymmetric fluoropolymer membranes comprised of a fluoropolymer material, wherein the membrane has a first surface comprised of a dense layer of the fluoropolymer material, and an opposite second surface comprised of a porous layer of the fluoropolymer material, and provides compositions for making the same.The present invention further provides a method for separating one or more organic compounds from a mixture of organic compounds or one or more organic compounds from water by pervaporation or vapor permeation, comprising the steps of:(a) placing an asymmetric fluoropolymer membrane comprised of a fluoropolymer material into a suitable pervaporation or vapor permeation apparatus such that the membrane forms a selectively permeable barrier to one or more compounds of the mixture, the membrane having a first surface comprised of a dense layer of the fluoropolymer material, and an opposite second surface comprised of a porous layer of the fluoropolymer material;(b) contacting the first surface of the membrane with the mixture; and(c) transporting permeate through the membrane by creating a difference in the partial pressure of the compounds between the first and second surfaces of the membrane.
摘要:
Improved polymer-based materials are described, for example for use as an electrode binder in a fuel cell. A fuel cell according to an example of the present invention comprises a first electrode including a catalyst and an electrode binder, a second electrode, and an electrolyte located between the first electrode and the second electrode. The electrolyte may be a proton-exchange membrane (PEM). The electrode binder includes one or more polymers, such as a polyphosphazene.
摘要:
An electrochemical process for hydrogenating an unsaturated fatty acid, mixtures of two or more fatty acids, or the unsaturated fatty acid constituents of an edible or non-edible oil's triglycerides is performed using a solid polymer electrolyte reactor. Membrane electrode assemblies consist of a cation exchange membrane onto which porous anode and cathode electrodes are attached. As the electrodes are permeable, reactant and products enter and leave the membrane/cathode and membrane/anode reaction zones via the back sides of the electrodes. Hydrogen is generated in situ by the electro-reduction of protons that are formed at the anode and which migrate through the ion exchange membrane for reaction with the fifty acids or fatty acid constituents. In the disclosed process, only protons (H+ ions) carry the current between the anode and the cathode. The need for a supporting electrolyte to conduct electricity has been circumvented. The disclosed process operates at a low to moderate temperature at atmospheric or moderate pressure without the use of a supporting electrolyte that will contaminate the oil. A novel partially hydrogenated oil product selected from the group consisting of a partially hydrogenated fatty acid, a partially hydrogenated triglyceride, and mixtures thereof is produced by the disclosed process. The product produced from the disclosed process has: a trans-isomer content lower than that of a similarly hydrogenated oil product formed in a high temperature chemical catalytic reaction process; a peroxide value of less than about 1.5%; free fatty acid content of less than about 0.02%; and, improved purity.
摘要:
Improved polymer-based materials are described, for example for use as an electrode binder in a fuel cell. A fuel cell according to an example of the present invention comprises a first electrode including a catalyst and an electrode binder, a second electrode, and an electrolyte located between the first electrode and the second electrode. The electrolyte may be a proton-exchange membrane (PEM). The electrode binder includes one or more polymers, such as a polyphosphazene.