Hitachi Metals, Ltd.

Mitsubishi Denki Kabushiki Kaisha

Hiroyuki Hoshi

Atsushi Okamoto

Setsuo Andou

Atsushi Kikugawa

Yu Miyamoto

Hitoshi Kurusu

Hiroki Yamamoto

Hajime Murakami

Motoyuki Miyata

Katsuyoshi Furusawa

A method for separating a light rare earth element and a heavy rare earth element includes at least the steps of: (1) obtaining, from a workpiece containing a light rare earth element and a heavy rare earth element, a composite oxide or mixture of oxides of the two; (2) dissolving the obtained composite oxide or mixture of oxides in hydrochloric acid and/or nitric acid; (3) adding a precipitant to the obtained solution to give a precipitate; (4) calcining the obtained precipitate; (5) adding the obtained calcine in an amount of 1.1 times to 3.0 times the upper solubility limit to hydrochloric acid and/or nitric acid having a concentration of 0.7 mol/L or more to give a solution and a residue; and (6) separating the obtained solution and residue, thereby giving the solution as a light rare earth element-rich inclusion and the residue as a heavy rare earth element-rich inclusion.

Useful method for separating light rare earth elements and heavy rare earth elements

An object of the present invention is to provide a method for recovering a rare earth element, including subjecting a workpiece containing at least a rare earth element and an iron group element to an oxidation treatment, then turning the treatment environment into an environment where carbon is present, and subjecting an oxidation-treated workpiece to a heat treatment, thereby separating a rare earth element in the form of an oxide from an iron group element, according to which an oxide of a rare earth element can be efficiently separated from an iron group element at low treatment cost, and also wear and damage to the treatment container can be suppressed to allow the container to be used repeatedly for a long period of time. The method of the present invention as a means for resolution is characterized in that the oxidation-treated workpiece is mixed with petroleum coke as a carbon supply source, placed in a treatment container, and then subjected to the heat treatment in an inert gas atmosphere or in vacuum at a temperature of 950&#xb0; C. to 1150&#xb0; C. (excluding 1150&#xb0; C.).

Method for recovering rare earth element

An object of the present invention is to provide a method for recovering a heavy rare earth element from a workpiece containing at least a heavy rare earth element and an iron group element, which can be put into practical use as a low-cost, simple recycling system. The method for recovering a heavy rare earth element from a workpiece containing at least a heavy rare earth element and an iron group element of the present invention as a means for resolution is characterized by including at least the following step: a workpiece is subjected to an oxidation treatment or mixed with an oxidation-treated R&#x2014;Fe&#x2014;B based magnet alloy, and then subjected to a heat treatment in the presence of carbon at a temperature of 1000&#xb0; C. or more, thereby separating a heavy rare earth element in the form of an oxide from an iron group element.

Method for recovering heavy rare earth element

An object of the present invention is to provide a method for recovering a rare earth element from a workpiece containing at least a rare earth element and an iron group element, which can be put into practical use as a low-cost, simple recycling system. The method for recovering a rare earth element from a workpiece containing at least a rare earth element and an iron group element of the present invention as a means for resolution is characterized by including at least a step of separating a rare earth element in the form of an oxide from an iron group element by subjecting a workpiece to an oxidation treatment, then turning the treatment environment into an environment where carbon black is present, and subjecting the oxidation-treated workpiece to a heat treatment at a temperature of 1000&#xb0; C. or more in an inert gas atmosphere or in vacuum.

An object of the present invention is to provide a method according to which a rare earth element can be efficiently recovered from a workpiece containing at least a rare earth element and an iron group element, and also wear and damage to the treatment container can be suppressed, allowing the container to be used repeatedly for a long period of time. The method of the present invention as a means for resolution is characterized in that in the heat treatment of an oxidation-treated workpiece in the presence of carbon, when the oxidation-treated workpiece is placed in a treatment container, a carbon substance is interposed between the oxidation-treated workpiece and the bottom surface of the container, and the heat treatment is performed in an inert gas atmosphere or in vacuum at a temperature of 1300&#xb0; C. or more.

An object of the present invention is to provide an aluminum foil that can make a positive electrode current collector thinner for size reduction and higher energy density of electrical storage devices, be produced easily and has a low surface resistance. An aluminum foil of the present invention as a means for achieving the object is characterized in that carbonaceous particles are dispersed and supported therein. The aluminum foil with carbonaceous particles dispersed and supported therein of the present invention can be produced by electrolysis.

Aluminum foil with carbonaceous particles dispersed and supported therein

An objective of the invention is to provide a method and system for separating a particular rare earth element from a rare earth magnet at a high separation ratio and by a simple process. There is provided a rare earth separation method for separating a first and a second groups of rare earth elements contained in a magnet, the method including: a starting powder preparation step from the magnet; a magnet component oxidation heat treatment step; a rare earth oxide separation step from the magnet components oxide powder; a powder size optimization step; a chlorinating agent mixing step; a chlorination/oxychlorination heat treatment step of forming a 'first group rare earth chlorides'/'second group rare earth oxychlorides' mixture; a selective dissolution step of selectively dissolving the first group rare earth chlorides in the solvent and leaving the second group rare earth oxychlorides undissolved in solid phase form; and a solid-liquid separation step.

Method and system for separating rare earth elements

An object of the present invention is to provide a method for recovering a rare earth element from a workpiece containing at least a rare earth element and an iron group element, which can be put into practical use as a low-cost, simple recycling system. The method of the present invention as a means for resolution is characterized by including at least a step of separating a rare earth element in the form of an oxide from an iron group element by subjecting a workpiece to an oxidation treatment, then turning the treatment environment into an environment where carbon is present, and subjecting the oxidation-treated workpiece to a heat treatment at a temperature of 1150&#xb0; C. or more.

A method for producing an aluminum foil of the present invention is characterized in that an aluminum film is formed on a surface of a substrate by electrolysis using a plating solution containing at least (1) a dialkyl sulfone, (2) an aluminum halide, and (3) at least one nitrogen-containing compound selected from the group consisting of an ammonium halide, a hydrogen halide salt of a primary amine, a hydrogen halide salt of a secondary amine, a hydrogen halide salt of a tertiary amine, and a quaternary ammonium salt represented by the general formula: RRRRN.X (Rto Rindependently represent an alkyl group and are the same as or different from one another, and X represents a counteranion for the quaternary ammonium cation), then the film is separated from the substrate to obtain an aluminum foil, and the obtained aluminum foil is subjected to a heat treatment.

Method for producing aluminum foil

An object of the present invention is to provide a method for producing a high-ductility, high-purity aluminum foil at a high film formation rate by electrolysis using a plating solution having a low chlorine concentration. A method for producing an aluminum foil of the present invention as a means for achieving the object is characterized in that an aluminum film is formed on a surface of a substrate by electrolysis using a plating solution at least containing (1) a dialkyl sulfone, (2) an aluminum halide, and (3) at least one nitrogen-containing compound selected from the group consisting of an ammonium halide, a hydrogen halide salt of a primary amine, a hydrogen halide salt of a secondary amine, a hydrogen halide salt of a tertiary amine, and a quaternary ammonium salt represented by a general formula: RRRRN.X (wherein Rto Rindependently represent an alkyl group and X represents a counteranion for the quaternary ammonium cation), and then the film is removed from the substrate.

An object of the present invention is to provide an extended-life plating solution that allows an aluminum electroplating process to be performed stably for a long period of time, and also a method for forming an aluminum plating film using the same. An aluminum electroplating solution according to the present invention is characterized by comprising 1.5 to 4.0 mol of an aluminum halide per 10.0 mol of dimethyl sulfone and, relative to the aluminum halide, ammonium chloride in a molar ratio of 1/15 to 1/4 or a tetraalkylammonium chloride in a molar ratio of 1/15 to 1/2. The plating solution has improved electrical conductivity and thus has a further advantage in that it allows the formation of a uniform aluminum plating film on a substrate to be plated even when the plating process is performed by a barrel method.

Aluminum electroplating solution and method for forming aluminum plating film

A plating film is provided with enough hardness before anodic oxidation, which is hard to be damaged during handling, and also the production method of the plating film. This problem can be solved by an aluminum plating film with aluminum concentration of 98 wt. % or lower, and with a Vickers hardness of 250 or higher. The hardness is increased by containing oxygen, carbon, sulfur, and a halogen element as impurities. The impurity concentration is controlled by adjusting the current density, the plating temperature, or the plating bath composition.

Aluminum plated film and metallic member

Aluminum plated film, metallic member, and its fabrication method

In a high frequency circuit property measurement method, prior to property measurements of a high frequency circuit with RF measurement probe heads, RF measurement probe heads are calibrated using a calibration pattern comprising a signal line having a characteristic impedance and extending on a dielectric substrate, a first GND pad having one end disposed close to and at an interval from a first end of the signal line, a second GND pad having one end disposed close to and at an interval from a second end of the signal line, and a conductor electrically coupling the first GND pad to the second GND pad.

Circuit property measurement method

A semiconductor device includes a metal-insulator-metal (MIM) capacitor having a lower metal layer disposed on a substrate, a dielectric film, and upper metal layers, a testing electrode pad connected to the lower metal layer of the MIN capacitor, two connecting terminals located on the substrate connected to the upper metal layers, and a field effect transistor (FET) having an electrode connected to one of the upper metal layers. By grounding the connecting terminals located on the substrate, and impressing a test voltage on the testing electrode pad, a withstand voltage test of the MIM capacitor can be conducted without damaging the FET.

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Mishima-gun, Japan

Hiroyuki Hoshi