Abstract: In producing a copper concentrate by flotation in which copper minerals are separated from arsenic minerals by using oxoacids of sulfur and oxidants, the arsenic in the copper concentrate is reduced by a simple method. In producing the copper concentrate by the flotation in which an arsenic-containing copper ore is a raw material, the oxoacids of sulfur and hydrogen peroxide as the oxidant are used together as additive reagents, and added in this order.

Abstract: An object of the present invention is to provide a semi-hard magnetic white powder having characteristics suitable as a security pigment, such as the magnetic powder contained in magnetic inks used for MICR. The white powder includes base particles made of a semi-hard magnetic Alnico alloy, the base particles having a titanium oxide film and a metallic silver film in this order on the surfaces thereof.

Abstract: Provided are cobalt ferrite particles having a micrometer-order average particle diameter and similar particle diameters. When a cobalt ferrite precursor is treated at a high temperature and a high pressure, an oxidation reaction is caused in the presence of a complexing agent, thereby obtaining intended cobalt ferrite magnetic particles.

Abstract: Provided are magnetic particles (cobalt ferrite) having a micrometer-order average particle diameter and similar particle diameters. A cobalt ferrite precursor is heated in the presence of a sulfite, thereby obtaining intended cobalt ferrite magnetic particles.

Abstract: Provided is a coating solution for forming a dust collecting layer, wherein the coating solution can be applied uniformly, and the formed dust collecting layer does not easily peel off from a filter element material, and allows to collect fine powder products having a small particle size. The coating solution is for forming a dust collecting layer in a dust collecting filter, and contains a fine powder, dopamine hydrochloride, and an adhesive.

Abstract: The present invention provides a method for producing lithium carbonate, that can shorten the time required in the production of lithium carbonate and has excellent maintenance property and production efficiency without forming fixed matters that require complicated procedures to remove in a reaction apparatus.

Abstract: The present invention provides a method for producing lithium carbonate, that can shorten the time required in the production of lithium carbonate and has excellent maintenance property and production efficiency without forming fixed matters that require complicated procedures to remove in a reaction apparatus.

Abstract: The present invention relates to a method for producing lithium carbonate, which is important as a raw material of a lithium ion battery and the like, from brine resources. More specifically, the invention relates to a method for producing lithium carbonate, in which carbon dioxide gas obtained by calcining limestone is introduced, in the presence of ammonia, into a concentrated brine, which is prepared from a lithium-containing brine as a raw material through an evaporative concentrating step, a desulfurizing step and an electrodialysis step, thereby depositing lithium carbonate crystals, and the crystals thus deposited are recovered through solid-liquid separation.

Abstract: The present invention relates to a method for producing lithium carbonate, the method including: mixing ammonia and carbon dioxide gas (carbonate gas) with an aqueous solution containing lithium chloride to conduct a carbonation reaction; and thereafter, recovering a produced solid by solid-liquid separation, and also relates to a method for producing high purity lithium carbonate.

Abstract: The present invention relates to a method for producing lithium carbonate, which is important as a raw material of a lithium ion battery and the like, from brine resources. More specifically, the invention relates to a method for producing lithium carbonate, in which carbon dioxide gas obtained by calcining limestone is introduced, in the presence of ammonia, into a concentrated brine, which is prepared from a lithium-containing brine as a raw material through an evaporative concentrating step, a desulfurizing step and an electrodialysis step, thereby depositing lithium carbonate crystals, and the crystals thus deposited are recovered through solid-liquid separation.

Abstract: The present invention relates to a method for producing lithium carbonate, the method including: mixing ammonia and carbon dioxide gas (carbonate gas) with an aqueous solution containing lithium chloride to conduct a carbonation reaction; and thereafter, recovering a produced solid by solid-liquid separation, and also relates to a method for producing high purity lithium carbonate.

Abstract: A method for producing a white powder, which includes forming on a surface of a base particle a titanium oxide film and a metallic silver film contiguously one upon another in this order, wherein the base particle includes a magnetic material, and wherein said step of forming on the surface of the base particle the titanium oxide film includes dispersing the base particle in a buffer solution and adding a titanium salt aqueous solution while agitating the dispersion.

Abstract: A method of treating hydrogen sulfide or producing hydrogen which comprises disposing a liquid tank having a photocatalyst electrode comprising a photocatalyst and a liquid tank having a metal electrode so that the two liquid tanks are separated from each other by a cation-exchange membrane, placing a liquid containing either hydrogen sulfide or an organic substance in the liquid tank having the photocatalyst electrode, electrically connecting the photocatalyst electrode to the metal electrode, and exposing the photocatalyst to a light. The liquid to be placed in the liquid tank having the metal electrode preferably is an acidic solution. The photocatalyst preferably comprises a metal sulfide, and preferably is fine particles having a layered nanocapsule structure.

Abstract: Basic magnesium carbonate comprising a tubular aggregated particle of flaky fine crystals.

Abstract: A photocatalyst which has high catalytic activity, is nontoxic, has a long life, can utilize visible light as it is for photocatalytic reactions, and is useful especially for hydrogen generation; and a process for producing the same. The photocatalyst comprises cadmium sulfide, has a capsule structure, wherein platinum is supported thereto. It can be obtainable by bubbling H2S gas into a liquid to which particles of cadmium oxide have been added.

Abstract: An apparatus for exciting a gas, comprising at least a pair of electrodes connecting to an alternating current source in a housing having an inlet opening for a gas to be treated and an outlet opening for a gas which has been treated, characterized in that one electrode of the pair of the electrodes is a suspended electrode arranged by placing it under a tension at a predetermined position in the housing, the other electrode of the pair of the electrodes is a buried electrode arranged at a predetermined position by being buried in the holding wall of the housing at the end thereof, an electrode portion of the buried electrode contains a linear or planar discharging portion as a whole, and the electrode portion of the suspended electrode, opposed to the electrode portion of the buried electrode, has discharging portions where a distance from the electrode portion of the buried electrode becomes cyclically short.

Abstract: Provided are a photocatalyst which is high in catalytic activity, is nontoxic, has a long life, allows visible light to be used directly for its photocatalytic reaction and is especially useful for hydrogen generation, and a process for producing it. It contains a cadmium compound, has a capsular structure, has an average particle diameter of 100 nm or less and can be manufactured by dropping a solution of a cadmium salt into a solution of a sodium compound or admixing a solution of a sodium compound in a suspension of particles of a cadmium compound.

Abstract: Optically coherent multilayered film-coated powder having weather resistance and a clear intended color, and processes for designing and producing the same are provided. A substance of the base particles providing an intended function and an intended color are selected; a spectral intensity curve and values in CIELAB color system of the intended color are measured; and with substances capable of being used as the coated layers and refractive indexes thereof being included in factors, substances and thicknesses of the coated layers and an order of formation of the layers are obtained that provide optically coherent multilayered film-coated powder having such values in CIELAB color system that minimizes a color difference and makes a hue ratio proximate to 1, by solving numerical solutions of the recurring formula for film multiple coherence.

Abstract: An apparatus for exciting a gas, comprising at least one pair of electrodes connecting with an alternate current electric source in a housing having an inlet opening for the gas to be treated and an outlet opening for a treated gas, the pair being a combination of a protected electrode and a protected electrode, or a combination of a protected electrode and an exposed electrode, wherein at least one protected electrode is composed of a core electrode with an insulating coating layer carried thereon and covering an entire surface thereof is disclosed.

Abstract: A technique is provided which enables highly efficient hydrogen sulfide decomposition and hydrogen generation with a photocatalyst. It is a method of treating hydrogen sulfide or producing hydrogen which comprises disposing a liquid tank having a photocatalyst electrode 1 comprising a photocatalyst and a liquid tank having a metal electrode 2 so that the two liquid tanks are separated from each other by a cation-exchange membrane 3, placing a liquid containing either hydrogen sulfide or an organic substance in the liquid tank having the photocatalyst electrode 3, electrically connecting the photocatalyst electrode 3 to the metal electrode 2, and exposing the photocatalyst to a light. The liquid to be placed in the liquid tank having the metal electrode 2 preferably is an acidic solution. The photocatalyst preferably comprises a metal sulfide, and preferably is fine particles having a layered nanocapsule structure.