Abstract: Systems, methods and apparatus relating to evaluation of alumina feedstocks are disclosed. A system may include an alumina storage unit comprising an alumina feedstock, an alumina supply member in communication with the alumina storage unit and an aluminum electrolysis cell. The alumina feedstock of the alumina storage unit may periodically flow through the alumina supply member and to the aluminum electrolysis cell. A measurement device may be in communication with the alumina supply member, and may be configured to measure a supply member property and transmit a first signal to a processor. The processor may be configured to receive the first signal and produce supply member property data based, at least in part, on the first signal.

Abstract: Systems, methods and apparatus relating to evaluation of alumina feedstocks are disclosed. A system may include an alumina storage unit comprising an alumina feedstock, an alumina supply member in communication with the alumina storage unit and an aluminum electrolysis cell. The alumina feedstock of the alumina storage unit may periodically flow through the alumina supply member and to the aluminum electrolysis cell. A measurement device may be in communication with the alumina supply member, and may be configured to measure a supply member property and transmit a first signal to a processor. The processor may be configured to receive the first signal and produce supply member property data based, at least in part, on the first signal.

Abstract: An electrolysis cell (10) contains a number of carbon anodes (12) having top, bottom and side surfaces, operating in molten electrolyte (17) in an aluminum electrolysis cell (10), where gas bubbles (28) are generated at the anode surfaces and where alumina particles (20) are added to the top of the molten electrolyte, where the carbon anodes (12) have at least two inward slots (21) passing through the carbon anode (12) along the longitudinal axis 40 of the carbon anode and also passing through only one front surface (25) of the carbon anode, where the height (32) of the slots (21) is from about 45% to 80% of the anodes thickness and the slotted front surfaces (25) are disposed toward the center of the electrolysis cell so that generated gas bubbles (28) are directed to the alumina particles.

Abstract: An electrolysis cell (10) contains a number of carbon anodes (12) having top, bottom and side surfaces, operating in molten electrolyte (17) in an aluminum electrolysis cell (10), where gas bubbles (28) are generated at the anode surfaces and where alumina particles (20) are added to the top of the molten electrolyte, where the carbon anodes (12) have one inward slot (21) passing through the carbon anode (12) along the longitudinal axis 40 of the carbon anode and also passing through only one front surface (25) of the carbon anode, where the height (32) of the slot (21) is from about 45% to 80% of the anodes thickness and the slotted front surfaces (25) are disposed toward the center of the electrolysis cell so that generated gas bubbles (28) are directed to the alumina particles.

Abstract: An electrolysis cell (10) contains a number of carbon anodes (12) having top, bottom and side surfaces, operating in molten electrolyte (17) in an aluminum electrolysis cell (10), where gas bubbles (28) are generated at the anode surfaces and where alumina particles (20) are added to the top of the molten electrolyte, where the carbon anodes (12) have at least two inward slots (21) passing through the carbon anode (12) along the longitudinal axis 40 of the carbon anode and also passing through only one front surface (25) of the carbon anode, where the height (32) of the slots (21) is from about 45% to 80% of the anodes thickness and the slotted front surfaces (25) are disposed toward the center of the electrolysis cell so that generated gas bubbles (28) are directed to the alumina particles.

Abstract: A cermet inert anode having a reduced level of contaminating surface metal is disclosed. Methods for preparing cermet inert anodes and methods for treating cermet inert anodes are also disclosed. The methods generally use an oxidizing agent to convert metals on the surface of the anode to inert oxides and/or to otherwise remove the metal contaminants. The inert anodes of the present invention may be used in electrolytic reduction cells for the production of commercial purity aluminum, as well as other metals.

Abstract: A cermet inert anode having a reduced level of contaminating surface metal is disclosed. Methods for preparing cermet inert anodes and methods for treating cermet inert anodes are also disclosed. The methods generally use an oxidizing agent to convert metals on the surface of the anode to inert oxides and/or to otherwise remove the metal contaminants. The inert anodes of the present invention may be used in electrolytic reduction cells for the production of commercial purity aluminum, as well as other metals.

Abstract: A method of making a light metal-rare earth metal alloy includes mixing a light metal powder, such as aluminum powder, with a finely divided rare earth metal-containing compound, such as scandium oxide, creating a billet by subjecting the mixture to cold isostatic compaction. The billet formed from the mixture of aluminum powder and rare earth metal-containing compound is preferably sintered at a temperature of about 600.degree. C. to 800.degree. C. and preferably about 640.degree. C. to 680.degree. C., and subsequently feeding the billet to a molten aluminum bath. This method facilitates conversion of in excess of 95% of the rare earth metal oxide to the aluminum-rare earth metal alloy. The rare earth metal may be scandium.

Abstract: A novel aluminum-lithium negative electrode and method for making such a novel aluminum-lithium negative electrode, including providing an admixture of aluminum powder and lithium halide electrolyte salts to form an aluminum lithium halide mixture, pressing the aluminum lithium halide mixture to form an aluminum lithium halide mixture negative electrode, placing the aluminum lithium halide mixture negative electrode next to a separate electrode composed of MgO and lithium halide electrolyte salts, providing a positive electrode of iron sulfide, lithium carbonate, and carbon, assembling the electrodes into a battery, and reacting lithium carbonate, carbon, and aluminum in situ in the battery to form an aluminum-lithium alloy negative electrode.

Abstract: There is disclosed an improved memory disk stock comprised of an alloy composition which includes: about 1-11 wt. % magnesium, preferably between about 2-7 wt. % Mg; up to about 0.3 wt. % zirconium preferably about 0.02-0.25 wt. % Zr; up to about 0.2 wt. % iron, up to about 0.2 wt. % silicon, and about 0.02-0.2 wt. % of a dispersoid-forming element selected from scandium, erbium, thulium, lutetium, ytterbium, hafnium and yttrium, the balance aluminum and incidental elements and impurities. With preferably about 0.05-0.15 wt. % of scandium added to such compositions, these disk stocks exhibit significant room temperature yield strength increases over the same compositions without any scandium added.

Abstract: A substantially nitrate-free solution for milling products of refractory metals, especially titanium, which milling solution comprises: (a) about 20-100 g/l hydrofluoric acid; (b) a hydrogen inhibitor selected from the group comprising of: about 55-650 g/l of sodium chlorate, about 180-650 g/l of ammonium peroxysulfate, and at least about 10 g/l of hydrogen peroxide; and (c) a balance of water and impurities. A method for chemically milling, etching and/or pickling metal products, such as titanium alloy forgings, with the aforementioned solution is also disclosed.

Abstract: A method for making a light metal-rare earth metal alloy comprises adding a pellet to a substantially flux-free bath of molten light metal, said pellet including a mixture of rare earth metal-containing compound and one or more light metal powders. On a preferred basis, such mixtures comprise scandium oxide, up to about 10 wt. % aluminum powder and a substantial majority of magnesium powder, all of which are substantially similar in median particle size. This mixture is preferably compacted under a pressure of about 7 kpsi or more, then added to a bath of molten magnesium or molten aluminum to make magnesium-scandium, magnesium-aluminum-scandium, or aluminum-magnesium-scandium alloys therefrom. There is further disclosed a method for making an alloy containing about 7-12 wt. % lithium, about 2-7 wt. % aluminum, about 0.4-2 wt. % scandium, up to about 2 wt. % zinc and up to about 1 wt. % manganese, the balance magnesium and impurities.

Abstract: A substantially nitrate-free solution for milling products of refractory metals, especially titanium, which solution contains: (a) about 5-100 g/l of ammonium bifluoride; (b) up to about 90 g/1 of hydrochloric acid; (c) a hydrogen inhibitor which may be either sodium chlorate or ammonium peroxysulfate; and (d) a balance of water and impurities. There is further disclosed a method for chemically milling, etching and/or pickling metal products, such as titanium alloy forgings, with the aforementioned solution.

Abstract: A method for making a light metal-rare earth metal alloy comprises adding a pellet to a bath of molten light metal, said pellet consisting essentially of a mixture of light metal powder and rare earth metal-containing compound. Such pellets, which are made under pressures of about 9 ksi or more, are preferably added to molten baths of aluminum, magnesium or combinations thereof. The light metal powders and rare earth metal-containing compounds that are mixed together to form said pellets are preferably substantially similar in terms of median particle size. This method is suitable for aluminothermically reducing scandium oxide to make aluminum-scandium alloy therefrom.

Abstract: The present invention provides a eutectic aluminum base alloy and anode made therefrom which may include at least two elements from the group consisting of scandium, bismuth, cadmium, gallium, indium, lead, mercury, thallium, tin, and zinc. The alloying elements are present in the aluminum alloy in such quantity that they are at least in part liquid at the sites of local reaction on the anode. The preferred alloying components are eutectics of the elements. The alloys and anodes have a high overpotential for water reduction. The purity of the aluminum is preferably at least about 99.99%. Preferred compositions are aluminum-gallium-indium, aluminum-gallium-indium-tin, aluminum-gallium-indium-tin-zinc, aluminum-gallium-indium-zinc, aluminum-gallium-zinc, aluminum-gallium-tin, and aluminum-bismuth-cadium-indium-lead-tin. The alloying elements may preferably be present in a total amount of about 0.01 to 3.0 percent based on total alloy weight. In an alternate embodiment a molten anode may be employed.

Abstract: The present invention provides in-situ electrolyte storage for batteries. The size of the reserve battery is significantly smaller due to the placement of an elastomeric sealed container within the interelectrode space of the battery. The sealed container contains the electrolyte. When punctured, the electrolyte flows out of the sealed container and into the electrode space. Substantially simultaneously, the elastomeric sealed container shrinks back allowing the electrolyte to flow into the interelectrode space allowing for the reaction. Preferably, the sealed container is made of elastomeric material that is flexible yet with good memory. This will allow the sealed container to shrink back to a small size when punctured. In addition, the sealed container should have have a low permeability to the electrolyte so as to minimize the amount of electrolyte that escapes from the sealed container while the electrolyte is being stored.

Abstract: An aluminum alloy contains at least about 0.01 to 0.2 weight percent gallium, at least about 0.01 to 0.2 weight percent tin, and at least about 0.01 to 0.2 weight percent lead. In another embodiment, the alloy may contain at least about 0.01 to 0.2 weight percent indium in lieu of the tin. The balance of both alloys is aluminum, tolerable levels of trace metals, and impurities. Preferably, the aluminum is present in 99.9% purity. The alloy can be used advantageously as an anode in an aluminum-air battery. The gallium-tin-lead aluminum alloy when used as an anode, is preferably used with a salt water electrolyte. The gallium-indium-lead alloy, when used as an anode is preferably used with a caustic electrolyte. The aluminum base alloy may be used as an anode in a battery assembly, a housing, an anode of the present invention, a cathode, and a support means within the housing to secure the anode and cathode in a relative spaced relationship.

Abstract: An electrolytic process comprising evolving oxygen on an anode in a molten salt, the anode comprising an alloy comprising a first metal and a second metal, both metals forming oxides, the oxide of the first metal being more resistant than the second metal to attack by the molten salt, the oxide of the second metal being more resistant than the first metal to the diffusion of oxygen. The electrode may also be formed of CuAlO.sub.2 and/or Cu.sub.2 O.

Abstract: The present invention discloses a method and apparatus for continuous analysis of a gas and particulate stream. More particularly, the present invention provides a method and apparatus for continuously analyzing a gas and particulate exhaust stream comprising metal fluorides to determine the fluoride concentration of such stream. A sampling nozzle communicating with a sampling line is placed in a gas and particulate stream. A gas-dissolving solvent is injected into a portion of the stream in the inlet portion of the sampling nozzle forming an aerosol. This portion of the stream and aerosol form a mixture comprising aerosol, gas and particulate which flows through the outlet portion of the sampling nozzle and through the sampling line. The aerosol in the mixture impinges against the inner surface of the sampling line wetting such inner surface with solvent; such mixture is scrubbed in the sampling line to enhance dissolution of gas in the solvent.

Abstract: A method for measuring fluoride concentrations in a gas wherein a sample of the gas is mixed with an internal reference solution in a gas scrubber to form a fluoride-containing solution. The fluoride-containing solution is collected, and the concentration of fluoride ion is determined in a potentiometric apparatus. The apparatus includes a first electrode having a fluoride-sensitive element and a second electrode having an element sensitive to a halide ion other than fluoride ion. The improved method of the invention compensates for errors caused by evaporation of water from the gas scrubber.