Abstract: A method of forming one or more ceramic layers on the substrate in which one layer containing ceramic particles is laminated onto the surface of the substrate that is completely formed. The layer that is applied to the substrate contains voids between the ceramic particles. The particles are sintered into a coherent mass, thereby to form the ceramic layer or layers by heating the layer while simultaneously applying pressure to the layer in a direction normal to the surface of the substrate until the sintering is complete. The layer is heated to a temperature that is below the pressureless sintering temperature of the particles and the temperature is sufficient to allow the movement of the particles upon application of the pressure to force the particles into physical contact with one another and such that the voids are substantially removed.

Abstract: A method of producing a green form for use in manufacturing a composite, ceramic ion transport membrane is provided in which first and second ceramic powder mixtures are used to produce first and second layers of the green form. The first and second ceramic powder mixtures have ceramic particles and a pore former. After formation of each of the first and second layers or after formation of the second layer, heat is applied to burn out the binder and form pores. This heating is completed prior to application of a dense layer to prevent production of defects within the dense layer. The dense layer contains an ion transport material. Defects are also prevented by grading particle size from the first layer to the dense layer. This allows the second intermediate layer to fill in larger pores of the first layer and to present a smooth surface to the dense layer. Additionally, the second ceramic powder mixture contains in part material used in forming the dense layer for thermal expansion compatibility purposes.

Abstract: A composite oxygen ion transport element that has a layered structure formed by a dense layer to transport oxygen ions and electrons and a porous support layer to provide mechanical support. The dense layer can be formed of a mixture of a mixed conductor, an ionic conductor, and a metal. The porous support layer can be fabricated from an oxide dispersion strengthened metal, a metal-reinforced intermetallic alloy, a boron-doped Mo5Si3-based intermetallic alloy or combinations thereof. The support layer can be provided with a network of non-interconnected pores and each of said pores communicates between opposite surfaces of said support layer. Such a support layer can be advantageously employed to reduce diffusion resistance in any type of element, including those using a different material makeup than that outlined above.

Abstract: A wall construction for an electrolytic cell to separate oxygen from an oxygen containing gas in which an electrolyte layer of less than 200 microns and a cathode layer of less than 500 microns are supported by an anode that can have a sufficient thickness to also contain the separated oxygen at pressure. The cathode is formed from the same material as the electrolyte and also a noble metal or noble metal alloy and a mixed conductor. The cathode contains a sufficient amount of the noble metal or noble metal allow and the mixed conductor that the total resistance thereof is not greater than about 70 percent of the total resistance of the anode and the cathode. In a preferred embodiment, first and second porous interfacial layers are situated between an anode layer and the electrolyte and the electrolyte and a cathode layer, respectively.

Abstract: A cold isopressing method and mold for compacting a granular ceramic material in which the granular ceramic material is introduced into a cylindrical pressure bearing element of an isopressing mold. The cylindrical pressure bearing element is sufficiently rigid so as to maintain its shape during the introducing of the granular ceramic material. Such element is also sufficiently resilient in a radial direction thereof to deform and bear against the granular ceramic material upon the application of the hydrostatic pressure and to substantially return to its original shape upon the relaxation of the hydrostatic pressure, thereby to allow retraction of the cylindrical pressure bearing element from the granular ceramic material after compaction. In a further aspect, an isopressing method and mold is provided in which the cylindrical pressure bearing element thereof is provided with an enlarged end bore to form an enlarged end section in the finished ceramic tube for sealing purposes.

Abstract: A method of producing a green form for use in manufacturing a composite, ceramic ion transport membrane is provided in which first and second ceramic powder mixtures are used to produce first and second layers of the green form. The first and second ceramic powder mixtures have ceramic particles and a pore former. After formation of each of the first and second layers or after formation of the second layer, heat is applied to burn out the binder and form pores. This heating is completed prior to application of a dense layer to prevent production of defects within the dense layer. The dense layer contains an ion transport material. Defects are also prevented by grading particle size from the first layer to the dense layer. This allows the second intermediate layer to fill in larger pores of the first layer and to present a smooth surface to the dense layer. Additionally, the second ceramic powder mixture contains in part material used in forming the dense layer for thermal expansion compatibility purposes.

Abstract: A wall construction for an electrolytic cell to separate oxygen from an oxygen containing gas in which an electrolyte layer of less than 200 microns and a cathode layer of less than 500 microns are supported by an anode that can have a sufficient thickness to also contain the separated oxygen at pressure. The cathode is formed from the same material as the electrolyte and also a noble metal or noble metal alloy and a mixed conductor. The cathode contains a sufficient amount of the noble metal or noble metal allow and the mixed conductor that the total resistance thereof is not greater than about 70 percent of the total resistance of the anode and the cathode. In a preferred embodiment, first and second porous interfacial layers are situated between an anode layer and the electrolyte and the electrolyte and a cathode layer, respectively.

Abstract: A method of making a porous, green form for use in producing at least part of an article that can be an oxygen transport membrane. A green powder, a binding agent, and first and second pore forming, particulate materials are mixed together. The first and second pore forming, particulate materials have first and second particle sizes such that the first particle size is greater than the second particle size. The difference in pore forming particle sizes allows for the production of large pores and channels connecting the pores in the finished article or part thereof. Advantageously, the first pore forming material is a sublimable material such as naphthalene. The mixture is formed into a configuration suitable for the use within the article, for instance a tube formed by extrusion. The first pore forming material is removed to form the pores. The oxygen transport membrane can have a dense layer supported by one or more porous support layers formed by a green form of the present invention.

Abstract: A cold isopressing method in which two or more layers of material are formed within an isopressing mold. One of the layers consists of a tape-cast film. The layers are isopressed within the isopressing mold, thereby to laminate the layers and to compact the tape-cast film. The isopressing mold can be of cylindrical configuration with the layers being coaxial cylindrical layers. The materials used in forming the layers can contain green ceramic materials and the resultant structure can be fired and sintered as necessary and in accordance with known methods to produce a finished composite, ceramic structure. Further, such green ceramic materials can be of the type that are capable of conducting hydrogen or oxygen ions at high temperature with the object of utilizing the finished composite ceramic structure as a ceramic membrane element.

Abstract: A ceramic membrane structure and method for separating oxygen from an oxygen containing feed at temperatures above about 600° C. The membrane is provided with a dense layer and one or more active porous layers. The dense layer contains at least a mixed conducting material and the active porous layer is formed of a mixture having an ion conducting phase capable of predominantly conducting oxygen ions and a mixed conducting phase capable of conducting both oxygen ions and electrons. The ion conducting phase is present within the mixture in an amount greater than a percolation threshold and the mixed conducting material and phase have a greater electronic conductivity than ionic conductivity.

Abstract: A cold isopressing method and mold for compacting a granular ceramic material in which the granular ceramic material is introduced into a cylindrical pressure bearing element of an isopressing mold. The cylindrical pressure bearing element is sufficiently rigid so as to maintain its shape during the introducing of the granular ceramic material. Such element is also sufficiently resilient in a radial direction thereof to deform and bear against the granular ceramic material upon the application of the hydrostatic pressure and to substantially return to its original shape upon the relaxation of the hydrostatic pressure, thereby to allow retraction of the cylindrical pressure bearing element from the granular ceramic material after compaction. In a further aspect, an isopressing method and mold is provided in which the cylindrical pressure bearing element thereof is provided with an enlarged end bore to form an enlarged end section in the finished ceramic tube for sealing purposes.

Abstract: A ceramic membrane structure and method for separating oxygen from an oxygen containing feed at temperatures above about 600° C. The membrane is provided with a dense layer and one or more active porous layers. The dense layer contains at least a mixed conducting material and the active porous layer is formed of a mixture having an ion conducting phase capable of predominantly conducting oxygen ions and a mixed conducting phase capable of conducting both said oxygen ions and electrons. The ion conducting phase is present within the mixture in an amount greater than a percolation threshold and the mixed conducting material and phase have a greater electronic conductivity than ionic conductivity.

Abstract: The present invention provides an ion conducting ceramic membrane selectively permeable to a gas, for instance oxygen and a method of treating such a membrane to improve permeation through the membrane. The membrane is formed by a mass of a substance through which ions of the gas migrate. The mass has two opposed surfaces where dissociation and ionization of the gas occurs and gas ions release electrons and recombine to form molecules of the gas, respectively. At least one of said two opposed surfaces is treated by a removal of surface material to produce surface irregularities of increased area and therefore an increase in total surface area of a treated surface to in turn increase permeation of the gas. Preferably, both surfaces of the membrane are treated by chemical etching techniques, although sand blasting and ion etching are other possible surface treatments in accordance with the present invention.

Abstract: An apparatus for distributing a high voltage arc from the high voltage ignition coil of a piston type internal combustion engine to the respective spark plug terminals by means of a high resistance, field-interrupting dielectric device which has an aperture therethrough defining a conductive path through the non-conductive dielectric device. The device is rotated in a fixed gap between the fixed location high voltage ignition coil electrode and the opposing spark plug terminal electrodes in such a manner so as to cause the aperture therethrough to pass directly between the electrodes which in turn allows a high voltage arc to bridge the fixed gap between the electrodes thus causing the spark plugs to be fired. When the aperture is not present in the fixed gap between the electrodes, the high resistance dielectric material of the device interrupts the electrical field between the electrodes, thus preventing an arc from bridging the gap and the spark plugs from being fired.