Abstract: Alkaline electrochemical cells are provided, wherein a conductive carbon is included in the cell's cathode in order to decrease resistivity of the cathode, so as to improve the discharge of the cell, particularly in high drain applications. The conductive carbon may comprise carbon nanotubes and/or graphene. Methods for preparing such cells are also provided.

Abstract: [Object] When rare earth magnets are plated, components of the rare earth magnets are dissolved in the plating solution, causing plating defects. Thus, an easy method for removing rare earth impurities has been necessary. [Means for Solution] A nickel-electroplating solution containing rare earth impurities is kept at 60° C. or higher for a predetermined period of time to precipitate rare earth impurities for separation by sedimentation or filtration. Rare earth impurities can be precipitated further efficiently by adding precipitate to the nickel-electroplating solution, or by concentrating the nickel-electroplating solution by heating.

Abstract: This invention relates to a method for the selective recovery of manganese and zinc from brines that includes the steps of contacting a brine with an ionic liquid in order to selectively extract manganese and zinc from the brine into the ionic liquid; and treating the ionic liquid containing extracted manganese and zinc with an aqueous solution to selectively precipitate manganese, producing a manganese depleted, zinc rich ionic liquid. The method can further include the steps of treating the manganese depleted, zinc rich ionic liquid with an aqueous solution to selectively precipitate zinc.

Abstract: Trimanganese tetraoxide has high reactivity with a lithium compound, is excellent in handling efficiency, and is suitable as a manganese material of a lithium manganese oxide, and its production process. Trimanganese tetraoxide particles including trimanganese tetraoxide primary particles having an average primary particle size of at most 2 ?m agglomerated, the pore volume of pores being at least 0.4 mL/g. The most frequent pores are preferably pores having a diameter of at most 5 ?m. The trimanganese tetraoxide particles can be obtained by producing trimanganese tetraoxide particles, which includes directly crystallizing trimanganese tetraoxide from a manganese salt aqueous solution, wherein the manganese salt aqueous solution and an alkali aqueous solution are mixed so that the oxidation-reduction potential is at least 0 mV and OH?/Mn2+ (mol/mol) is at most 0.55, to obtain a slurry, and the solid content concentration of the slurry is adjusted to be at most 2 wt %.

Abstract: To provide metal-containing trimanganese tetraoxide combined particles with which a metal-substituted lithium manganese oxide excellent as a cathode material for a lithium secondary battery can be obtained, and their production process. Metal-containing trimanganese tetraoxide combined particles containing a metal element (excluding lithium and manganese). Such metal-containing trimanganese tetraoxide combined particles can be obtained by a production process comprising a crystallization step of crystalizing a metal-substituted trimanganese tetraoxide not by means of metal-substituted manganese hydroxide from a manganese salt aqueous solution containing manganese ions and metal ions other than manganese.

Abstract: The invention is directed to a method for producing metal-containing particles, the method comprising subjecting an aqueous solution comprising a metal salt, Eh, lowering reducing agent, pH adjusting agent, and water to conditions that maintain the Eh value of the solution within the bounds of an Eh-pH stability field corresponding to the composition of the metal-containing particles to be produced, and producing said metal-containing particles in said aqueous solution at a selected Eh value within the bounds of said Eh-pH stability field. The invention is also directed to the resulting metal-containing particles as well as devices in which they are incorporated.

Abstract: The invention is directed to a method for producing metal-containing (e.g., non-oxide, oxide, or elemental) nano-objects, which may be nanoparticles or nanowires, the method comprising contacting an aqueous solution comprising a metal salt and water with an electrically powered electrode to form said metal-containing nano-objects dislodged from the electrode, wherein said electrode possesses a nanotextured surface that functions to confine the particle growth process to form said metal-containing nano-objects. The invention is also directed to the resulting metal-containing compositions as well as devices in which they are incorporated.

Abstract: Disclosed is an electrolytic manganese dioxide having an alkali potential of at least 310 mV, a full width at half maximum of the (110) plane in the XRD measurement using the CuK? line as the light source of from 2.2° to 3.0°, and a (110)/(021) peak intensity ratio in the X-ray diffraction spectrum of from 0.5 to 0.80. Also disclosed is a method for producing electrolytic manganese dioxide by electrolysis in an aqueous solution of a sulfuric acid/manganese sulfate mixture.

Abstract: Disclosed is an electrolytic manganese dioxide having an alkali potential of at least 310 mV, a full width at half maximum of the (110) plane in the XRD measurement using the CuK? line as the light source of from 2.2o to 3.0o, and a (110)/(021) peak intensity ratio in the X-ray diffraction spectrum of from 0.5 to 0.80. Also disclosed is a method for producing electrolytic manganese dioxide by electrolysis in an aqueous solution of a sulfuric acid/manganese sulfate mixture.

Abstract: This invention relates to a method for the selective recovery of manganese and zinc from geothermal brines that includes the steps of removing silica and iron from the brine, oxidizing the manganese and zinc to form precipitates thereof, recovering the manganese and zinc precipitates, solubilizing the manganese and zinc precipitates, purifying the manganese and zinc, and forming a manganese precipitate, and recovering the zinc by electrochemical means.

Abstract: Disclosed is an electrolytic manganese dioxide having an alkali potential of at least 310 mV, a full width at half maximum of the (110) plane in the XRD measurement using the CuK? line as the light source of from 2.2o to 3.0o, and a (110)/(021) peak intensity ratio in the X-ray diffraction spectrum of from 0.5 to 0.80. Also disclosed is a method for producing electrolytic manganese dioxide by electrolysis in an aqueous solution of a sulfuric acid/manganese sulfate mixture.

Abstract: This invention relates to a method for the selective recovery of manganese and zinc from geothermal brines that includes the steps of removing silica and iron from the brine, oxidizing the manganese and zinc to form precipitates thereof, recovering the manganese and zinc precipitates, solubilizing the manganese and zinc precipitates, purifying the manganese and zinc, and forming a manganese precipitate, and recovering the zinc by electrochemical means.

Abstract: Provided is a method for producing mercury-free alkaline-manganese type electrolyzed manganese dioxide, which sequentially comprises: (1) mixing manganese oxide ore and pyrite, continuously feeding the mixture and sulfuric acid into a continuous leaching tank to form a one-stage or multi-stage continuous leaching, removing potassium ions first after leaching, and then removing iron by means of a neutral iron removal method, and adding lime powder at the late stage of iron removal to adjust the pH value of the solution to 6-6.5, so as to obtain a manganese sulfate solution after reaction at 90-95° C.

Abstract: A primary battery includes a cathode having an acid-treated manganese dioxide, an anode, a separator between the cathode and the anode, and an alkaline electrolyte.

Abstract: According to one embodiment, a process for producing rare metals includes the steps of: electrolyzing an electrolytic solution to extract a Re oxide at a cathode; recovering the Re oxide, and electrolyzing the Re oxide in a molten salt electrolyte to extract metallic Re; recovering a Nd containing residue solution; treating the Nd containing residue solution to produce Nd oxide; electrolyzing the Nd oxide in a molten salt electrolyte to extract metallic Nd; recovering a Dy containing residue solution; treating the Dy containing residue solution to produce Dy oxide; and electrolyzing the Dy oxide in a molten salt electrolyte to extract metallic Dy.

Abstract: An electric current is passed through an acidic solution containing one or more soluble metal salts in an electrolytic cell divided by an anion exchange membrane. The acidic solution is fed into the cathode compartment whereby the passage of electric current at sufficient voltage causes the generation of hydrogen at the cathode. This gives rise to a localized very highly polarized region at the cathode resulting in a localized effective high relative pH. This causes the metal cation species to precipitate as a hydroxide (or oxide) species and electroadsorption/electrocoagulation causes the finely precipitated hydroxide (or oxide) species to adhere to the cathode. Electrodialytic transport of the liberated acid anions across the anion exchange membrane selectively removes the acid anions. Oxygen and hydrogen ions are formed by hydrolysis as the counter-reaction at the anode. Hydrogen ions combine with the anions to regenerate sulfuric acid.

Abstract: An object of the present invention is to provide electrolytic manganese dioxide to be used as a cathode active material for an alkali-manganese dry cell, which has a high alkali potential and is provided with a high reactivity and packing efficiency as a cathode for the cell, and which is excellent in the middle rate discharge characteristic, and electrolytic manganese dioxide excellent in the high rate discharge characteristic and the middle rate discharge characteristic, which will not cause corrosion of metal materials, and a method for its production. In the present invention, electrolytic manganese dioxide having an alkali potential of at least 280 mV and less than 310 mV, and FWHM of at least 2.2° and at most 2.9°, is used. It is preferred that of the electrolytic manganese dioxide, the (110)/(021) peak intensity ratio in the X-ray diffraction peaks is at least 0.50 and at most 0.80, and the (110) interplanar spacing is at least 4.00 ? and at most 4.06 ?.

Abstract: A process for the hydrometallurgical processing of manganese containing materials, the process characterized by the combination of a manganese dioxide containing feedstock and an acidic solution to form an acidic solution to be leached, and passing a volume of sulphur dioxide gas through that leach solution as the leaching agent, whereby no sintering or roasting pre-treatment step of the feedstock is undertaken and the levels of dithionate ion generated in the leach solution are less than about 5 g/l. Also described is a process for the production of electrolytic manganese dioxide.

Abstract: Electrolytic manganese dioxide for lithium primary batteries has a sodium content of 0.05 to 0.2% by mass, and a pH of 5 to 7 as measured according to JIS-K-1467. Using this electrolytic manganese dioxide as a positive electrode active material for lithium primary batteries enables the batteries to be excellent in both initial discharge characteristics and long-term discharge characteristics.

Abstract: This invention relates generally to a process of producing electrolytic manganese dioxide (EMD). More specifically, a method of producing EMD from geothermal brine solutions is provided. Methods for production of manganese dioxide from geothermal brines through an electrolytic process are also provided.

Abstract: There is provided a composite plated product which has a large content of carbon and a large quantity of carbon particles on the surface thereof and which has an excellent wear resistance, by sufficiently dispersing carbon particles in a silver plating solution without using any additives such as dispersing agents and without coating the surface of carbon particles. A wet oxidation treatment for carbon particles is carried out by adding an oxidizing agent to water in which the carbon particles are suspended, and the carbon particles treated by the wet oxidation treatment are added to a cyanide containing silver plating solution for electroplating a substrate to form a coating of a composite material, which contains the carbon particles in a silver layer, on the substrate.

Abstract: In order to regenerate permanganate solutions being utilized for the etching and roughening of plastics surfaces electrolytic methods are known. Though relatively small quantaties of by-products are produced with these methods as compared to chemical regeneration methods, large quantaties of manganese dioxide are produced when printed circuit boards are treated. In order to avoid formation of manganese dioxide during the regeneration method a novel cathode 2 has been found which is provided with a porous, electrically nonconducting layer 7 on the cathode body 3. The layer 7 preferably consists of a plastics material being resistant to acid and/or alkali.

Abstract: Using a solution mining procedure, an ore (10) is treated with a solution of acetic acid and hydrogen peroxide so as to form a leachate containing lead ions. Lead ions (and other metal ions such as zinc and manganese) are stripped (22, 24, 26) by solvent extraction from the leachate to form separate aqueous solutions. The aqueous solution containing lead ions is treated electrochemically in the anodic compartment of a separated electrochemical cell (42) to form a precipitate of lead oxide. Manganese dioxide can be produced similarly (72). A precipitate of zinc hydroxide can be formed in the cathode compartment of a separated electrochemical cell (56). In the cells (42, 72) extracting lead ions and manganese ions, the cathode compartment is used to generate hydrogen peroxide (for use in making the leachant), either directly or indirectly.

Abstract: This invention relates generally to a process of producing electrolytic manganese dioxide (EMD). More specifically, a method of producing EMD from geothermal brine solutions is provided. Methods for production of manganese dioxide from geothermal brines through an electrolytic process are also provided.

Abstract: The present invention provides a battery cathode active material formed of electrolytic manganese dioxide which has a large specific area and a high electric potential and can enhance battery characteristics such as high-rate characteristics and high-rate pulse characteristics when used as a battery cathode active material. The invention also provides a method for producing electrolytic manganese dioxide and a battery employing the cathode active material. The battery cathode active material is formed of electrolytic manganese dioxide containing a sulfate group in an amount of 1.3 to 1.6 wt. %.

Abstract: This invention relates generally to a process of producing electrolytic manganese dioxide (EMD). More specifically, a method of producing EMD from geothermal brine solutions is provided. Methods for production of manganese dioxide from geothermal brines through an electrolytic process are also provided.

Abstract: A powder of electrolytic manganese dioxide and a process for producing the same are disclosed. The powder has a maximum particle diameter of 100 &mgr;m or smaller, a content of 1 &mgr;m and smaller particles of lower than 15% by number, and a median diameter of from 20 to 60 &mgr;m, and which has a potential of 270 mV or higher in terms of the potential of a suspension of the powder in 40% aqueous KOH solution as measured using a mercury/mercury oxide reference electrode as a base.

Abstract: A process for manufacture of manganese dioxide comprising subjecting an aqueous bath comprising manganese sulfate (MnSO4) and sulfuric acid (H2SO4) to electrolysis in a closed cell wherein the electrolysis bath is maintained at an elevated temperature above 110° C., preferably above 115° C. and at superatmospheric pressure. Desirably the bath can be maintained at an elevated temperature between about 115° C. and 155° C. The electrolysis is carried out preferably at elevated current density of between about 12.5 and 37 Amp/sq. ft (135 and 400 Amp/sq. meter) which allows for smaller or fewer electrolysis units. An MnO2 product having a specific surface area (SSA) within desired range of between 18-45 m2/g can be obtained. A doping agent, preferably a soluble titanium dopant is employed to help obtain the desired specific surface area (SSA) of the MnO2 product. The manganese dioxide product in zinc/MnO2 alkaline cells gives excellent service life, particularly in high power application.

Abstract: The present invention provides improved cathode material comprised of electrolytic manganese dioxide having high discharge capacity at high discharge rates and methods of producing such electrolytic manganese dioxide by electrolysis in an electrolytic cell. The methods are basically comprised of maintaining a heated high purity aqueous electrolyte solution comprising specific amounts of sulfuric acid and manganese sulfate in the electrolytic cell and maintaining the amounts of the sulfuric acid and manganese ion in the solution at a ratio of sulfuric acid to manganese ion greater than 2. An electric current is applied to the electrodes of the electrolytic cell whereby the anodic electrode current density is in the range of from about 2.5 to about 6 amperes per square foot and the high discharge capacity EMD produced is deposited on the anodic electrode.

Abstract: The process for preparing spinel-type lithium manganate according to the present invention is constituted by a process to admix the electrolyzed manganese dioxide, which is obtained by neutralizing manganese dioxide precipitated by means of electrolysis with any of potassium hydroxide, potassium carbonate and lithium hydroxide, and a lithium material and a process to subject the resulting mixture to a sintering process.

Abstract: Aqueous solutions containing lead, zinc and manganese are treated to recover these metals by sequential solvent extraction steps. Solvent extractants are selected to extract preferentially lead, then zinc and then manganese in that order. Any interfering metals are removed (as by ion exchange) before extraction. The loaded extractant phases are stripped with selected acids and lead, zinc and manganese each recovered from the strip solutions. Optionally calcium can be recovered when present. A preferred type of extractant (for lead especially) is substituted monothiophosphinic acids. A closed loop system is described which is advantageous with leachate from sulphide and carbonate ores.

Abstract: A process for manufacture of manganese dioxide comprising subjecting an aqueous bath comprising manganese sulfate (MnSO4) and sulfuric acid (H2SO4) to electrolysis in a closed cell wherein the electrolysis bath is maintained at an elevated temperature above 110° C., preferably above 115° C. and at superatmospheric pressure. Desirably the bath can be maintained at an elevated temperature between about 115° C. and 155° C. The electrolysis is carried out preferably at elevated current density of between about 12.5 and 37 Amp/sq.ft (135 and 400 Amp/sq. meter) of the anode surface which allows for smaller or fewer electrolysis units. An MnO2 product having a specific surface area (SSA) within desired range of between 18-45 m2/g can be obtained. A doping agent, preferably a soluble titanium dopant can also be employed to help obtain the desired specific surface area (SSA) of the MnO2 product.

Abstract: Using a solution mining procedure, an ore (10) is treated with a solution of acetic acid and hydrogen peroxide so as to form a leachate containing lead ions. Lead ions (and other metal ions such as zinc and manganese) are stripped (22, 24, 26) by solvent extraction from the leachate to form separate aqueous solutions. The aqueous solution containing lead ions is treated electrochemically in the anodic compartment of a separated electrochemical cell (42) to form a precipitate of lead oxide. Manganese dioxide can be produced similarly (72). A precipitate of zinc hydroxide can be formed in the cathode compartment of a separated electrochemical cell (56). In the cells (42, 72) extracting lead ions and manganese ions, the cathode compartment is used to generate hydrogen peroxide (for use in making the leachant), either directly or indirectly.

Abstract: A powder of electrolytic manganese dioxide and a process for producing the same are disclosed. The powder has a maximum particle diameter of 100 &mgr;m or smaller, a content of 1 &mgr;m and smaller particles of lower than 15% by number, and a median diameter of from 20 to 60 &mgr;m, and which has a potential of 270 mV or higher in terms of the potential of a suspension of the powder in 40% aqueous KOH solution as measured using a mercury/mercury oxide reference electrode as a base.

Abstract: The present invention provides improved cathode material comprised of electrolytic manganese dioxide having high discharge capacity at high discharge rates and methods of producing such electrolytic manganese dioxide by electrolysis in an electrolytic cell. The methods are basically comprised of maintaining a heated high purity aqueous electrolyte solution comprising specific amounts of sulfuric acid and manganese sulfate in the electrolytic cell and maintaining the amounts of the sulfuric acid and manganese ion in the solution at a ratio of sulfuric acid to manganese ion greater than 2. An electric current is applied to the electrodes of the electrolytic cell whereby the anodic electrode current density is in the range of from about 2.5 to about 6 amperes per square foot and the high discharge capacity EMD produced is deposited on the anodic electrode.

Abstract: The present invention provides improved cathode material comprised of electrolytic manganese dioxide having high discharge capacity at high discharge rates and methods of producing such electrolytic manganese dioxide by electrolysis in an electrolytic cell. The methods are basically comprised of maintaining a heated high purity aqueous electrolyte solution comprising sulfuric acid and manganese sulfate in the electrolytic cell, the manganese sulfate being present in the solution whereby it contains in the range of from about 5 to about 50 grams of manganese per liter of solution. An electric current is applied to the electrodes of the electrolytic cell whereby the anodic electrode current density is in the range of from about 2.5 to about 6 amperes per square foot.

Abstract: Using the electrolytic process to make manganese metal, a source of manganomanganic oxide (Mn.sub.3 O.sub.4) is used in the sulfuric acid leach solution in conjunction with a reducing agent to convert the manganomanganic oxide into manganese sulfate for treatment in the electrolytic cell. Sources of manganomanganic oxide include sintered manganese ore, manganese ore having less than 7% available oxygen such as Assoman Ore, and MOR fume. Reducing agents include sulfur dioxide, activated carbon, reducing sugars and molasses.

Abstract: An electrolytic manganese dioxide having a composition of MnOx, wherein X is 1.90 to 1.96, an adhesive moisture content of not less than 1.5% by weight as measured according to the procedure specified in JIS, and a content of bound water, eliminative in the temperature range of 120.degree. to 400.degree. C., of not less than 3.0% by weight as measured by gravimetry, a process for preparing the same, and a manganese dry cell comprising a cathode mix comprised of a mixing of the electrolytic manganese dioxide with a conductive acetylene black, preferably a conductive acetylene black having a BET specific surface area of 70 to 2.50 m.sup.2 /g, and an electrolyte composed mainly of zinc chloride and/or ammonium chloride. In the process of preparing the electrolytic manganese dioxide, after electrolysis and during or after neutralization, the manganese dioxide is heated in an aqueous solution at 50.degree. to 100.degree. C. for 12 to 48 hours in the presence of an alkaline ammonium compound.

Abstract: Disclosed is a process for treating manganese dioxide containing ion-exchangeable cations by replacing the ion-exchangeable cations present in the manganese dioxide with lithium by a process comprising first replacing ion-exchangeable cations present in the manganese dioxide with hydrogen. This readily is accomplished by slurrying the manganese dioxide in an aqueous acid solution. The resulting acidic manganese dioxide then is neutralized with a basic solution of a lithium containing compound, such as lithium hydroxide. This neutralization step serves to accomplish replacement of the previously introduced hydrogen, by ion-exchange, with lithium. The manganese dioxide then is washed with water, dried, and heat-treated at an elevated temperature, in conventional manner, to convert the gamma manganese dioxide to a mixture of the gamma and beta forms, which then is used as the active cathodic component in an electrochemical cell.

Abstract: There is provided manganese dioxide to be suitably used for alkaline manganese batteries and manganese batteries to make them excellent both in the initial performance and the storability. There is also provided a method of manufacturing such manganese dioxide. The electrolytic manganese dioxide has a BET specific surface area of less than 30 m.sup.2 /g (preferably less than 27 m.sup.2 /g) and a suspensiveness of less than 50 mg/liter. A method of manufacturing electrolytic manganese dioxide may be a suspension method, wherein manganese oxide is suspended at a rate of 0.01 to 0.2 g/liter in an electrolytic bath containing sulfuric acid at a concentration of 0.4 to 0.55 mol/liter and electrolyzed to produce electrolytic manganese dioxide with an anodic current density of 0.4 to 3.0 A/dm.sup.2 and an electrolytic temperature of 93.degree. to 103.degree. C., the relationship between the anodic current density and the electrolytic temperature being expressed by 103.gtoreq.y.gtoreq.1.67x+92.

Abstract: Disclosed is a process for treating manganese dioxide containing ion-exchangeable cations by replacing the ion-exchangeable cations present in the manganese dioxide with lithium by a process comprising first replacing ion-exchangeable cations present in the manganese dioxide with hydrogen. This readily is accomplished by slurrying the manganese dioxide in an aqueous acid solution. The resulting acidic manganese dioxide then is neutralized with a basic solution of a lithium containing compound, such as lithium hydroxide. This neutralization step serves to accomplish replacement of the previously introduced hydrogen, by ion-exchange, with lithium. The manganese dioxide then is washed with water, dried, and heat-treated at an elevated temperature, in conventional manner, to convert the gamma manganese dioxide to a mixture of the gamma and beta forms, which then is used as the active cathodic component in an electrochemical cell.

Abstract: Insertion compounds that are not stable in pure water can be prepared by an aqueous electrochemical method. The pH of the electrolyte and/or the concentration of ions of the inserted species must be sufficiently high to provide stability for the product compound. The method is useful for further lithiation of conventional lithium ion battery cathode materials.