Abstract: A method for recovering scandium, by which scandium is able to be recovered from nickel oxide ore. The present invention comprises: a leaching step S1 for obtaining a leachate by leaching a nickel oxide ore containing scandium with use of sulfuric acid; a neutralization step by adding a neutralizing agent thereto; a sulfurization step by adding a sulfurizing agent to the post-neutralization solution; an ion exchange step by bringing the post-sulfurization solution into contact with a chelating resin; a dissolution step by obtaining a precipitate of scandium hydroxide by adding an alkali into the scandium eluent, and subsequently adding an acid solution to the scandium hydroxide; a solvent extraction step by bringing the scandium acid dissolution liquid into contact with a neutral extractant; and a scandium recovery step by adding oxalic acid to the extraction residue and subsequently roasting the salt of scandium oxalate.

Abstract: A method for recovering scandium, by which scandium is able to be recovered from nickel oxide ore. The present invention comprises: a leaching step S1 for obtaining a leachate by leaching a nickel oxide ore containing scandium with use of sulfuric acid; a neutralization step by adding a neutralizing agent thereto; a sulfurization step by adding a sulfurizing agent to the post-neutralization solution; an ion exchange step by bringing the post-sulfurization solution into contact with a chelating resin; a dissolution step by obtaining a precipitate of scandium hydroxide by adding an alkali into the scandium eluent, and subsequently adding an acid solution to the scandium hydroxide; a solvent extraction step by bringing the scandium acid dissolution liquid into contact with a neutral extractant; and a scandium recovery step by adding oxalic acid to the extraction residue and subsequently roasting the salt of scandium oxalate.

Abstract: The invention provides a method for recovering scandium from an acidic solution containing scandium. The method having [a] a precipitation step wherein sodium sulfate is added into the acidic solution containing scandium to obtain a precipitate of a scandium double sulfate; [b] a neutralization step wherein pure water is added to the precipitate of a scandium double sulfate to dissolve the precipitate of a scandium double sulfate therein, and scandium hydroxide is obtained by adding a neutralizing agent into the dissolution liquid; and [c] a re-dissolution step wherein an acid is added to the scandium hydroxide obtained in the neutralization step, so that a scandium dissolution after purification, in which the scandium hydroxide is dissolved, is obtained.

Abstract: A wet smelting method for nickel oxide ores from which nickel, cobalt, etc. are recovered is provided with which it is possible to reduce the consumption of an acid in leaching, such as sulfuric acid, and to recover valuable metals. The method comprises: step (A) in which nickel oxide ores as a raw material are separated into a limonite-type ore having a low magnesium content and a saprolite-type ore having a high magnesium content; step (B) in which the saprolite-type ore is subjected to normal-pressure leaching under given standardized leaching conditions using the pressure leachate obtained by pressure leaching in step (C); and step (C) in which the limonite-type ore obtained in step (A) is mixed with the normal-pressure leaching residue obtained in step (B) and the mixture is reacted with sulfuric acid in an acidic atmosphere having a high temperature and a high pressure, thereby conducting pressure leaching.

Abstract: Provided is a method for recovering scandium, with which it is possible to easily and efficiently recover high-purity scandium from nickel oxide ores. This method for recovering scandium involves passing a solution containing scandium through an ion exchange resin, then subjecting the eluant eluted from the ion exchange resin to solvent extraction and separating the extraction residual liquid and the extraction agent after extraction, then performing an oxalation process on the extraction residual liquid to obtain a scandium oxalate precipitate, and roasting the precipitate to obtain scandium oxide, wherein the method is characterized in that an amine-based extraction agent is used as the extraction agent for solvent extraction.

Abstract: In order to recover high-quality scandium from nickel oxide ores efficiently, this method comprises: a step (S1) for feeding Ni oxide ores and sulfuric acid into a pressure vessel, and subjecting the mixture to solid-liquid separation to form a leachate and a leach residue; a step (S2) for adding a neutralizing agent to the leachate, and thus forming a neutralization sediment and a post-neutralization fluid; a step (S3) for adding a sulfurizing agent to the post-neutralization fluid, and separating the obtained mixture into Ni sulfide and a post-sulfurization fluid; a step (S4) for bringing the post-sulfurization fluid into contact with a chelating resin, making Sc adsorbed on the chelating resin, and forming an Sc eluent; a step (S6) for bringing the Sc eluent into contact with an extracting agent, adding a back-extraction agent to the extract, and forming back-extracted matter; and a step (S8) for roasting the back-extracted matter, and forming Sc oxide.

Abstract: According to this method for recovering scandium, an acidic solution containing scandium is used and a scandium dissolution liquid after purification is obtained by a double sulfate precipitation step, and scandium is recovered from the obtained scandium dissolution liquid, as follows: [A] A precipitation step wherein sodium sulfate is added into the acidic solution containing scandium, so that a precipitate of a scandium double sulfate is obtained; [B] A neutralization step wherein pure water is added to the precipitate of a scandium double sulfate obtained in the precipitation step to dissolve the precipitate of a scandium double sulfate therein, and scandium hydroxide is obtained by adding a neutralizing agent into the obtained dissolution liquid; and [C] A re-dissolution step wherein an acid is added to the scandium hydroxide obtained in the neutralization step, so that a scandium dissolution after purification, in which the scandium hydroxide is dissolved, is obtained.

Abstract: A wet smelting method for nickel oxide ores from which nickel, cobalt, etc. are recovered is provided with which it is possible to reduce the consumption of an acid in leaching, such as sulfuric acid, and to recover valuable metals. The method comprises: step (A) in which nickel oxide ores as a raw material are separated into a limonite-type ore having a low magnesium content and a saprolite-type ore having a high magnesium content; step (B) in which the saprolite-type ore is subjected to normal-pressure leaching under given standardized leaching conditions using the pressure leachate obtained by pressure leaching in step (C); and step (C) in which the limonite-type ore obtained in step (A) is mixed with the normal-pressure leaching residue obtained in step (B) and the mixture is reacted with sulfuric acid in an acidic atmosphere having a high temperature and a high pressure, thereby conducting pressure leaching.

Abstract: Provided is a method for recovering scandium, with which it is possible to easily and efficiently recover high-purity scandium from nickel oxide ores. This method for recovering scandium involves passing a solution containing scandium through an ion exchange resin, then subjecting the eluant eluted from the ion exchange resin to solvent extraction and separating the extraction residual liquid and the extraction agent after extraction, then performing an oxalation process on the extraction residual liquid to obtain a scandium oxalate precipitate, and roasting the precipitate to obtain scandium oxide, wherein the method is characterized in that an amine-based extraction agent is used as the extraction agent for solvent extraction.

Abstract: The wastewater treatment method is to obtain demanganized wastewater, through a step wherein an acid or an alkali is added to sulfuric acid acidified wastewater to adjust pH to not less than 4.0 and not more than 6.0, whereby the sulfuric acid acidified wastewater is separated into a dealuminized solution and an aluminum precipitate; a step wherein a slurrying solution is added to the aluminum precipitate to form a slurry, then an alkali is added to adjust pH to not less than 9.0 and not more than 9.5, whereby an pH-adjusted aluminum precipitate slurry is formed; a step wherein an alkali is added to the dealuminized solution to adjust pH to not less than 8.0 and not more than 9.0; and others.

Abstract: A removal method of manganese in which manganese is removed by precipitating manganese selectively from sulfuric acid waste water containing aluminum, magnesium and manganese with inhibiting the precipitation of magnesium. The removal method of manganese from waste water in which manganese is removed by precipitating manganese selectively from the sulfuric acid waste water containing aluminum, magnesium and manganese with inhibiting the precipitation of magnesium, characterized in that said waste water is subjected to the following steps (1) and (2). (1) First, aluminum in said waste water is removed. (2) Subsequently, neutralizing agent is added into the wastewater after removing aluminum, then pH of the waste water is adjusted at 8.0 to 9.0, and oxygen gas is blown.

Abstract: Provided are an impurity-element removing method for selectively removing magnesium from a nickel-containing solution, and a method for producing high-purity nickel sulfate using the impurity-element removing method.

Abstract: A traveling drive device for a dump truck is provided with an axle housing mounted to a vehicle body, a wheel mounting tube rotatably provided on the outer periphery side of the axle housing, a disk holding cylinder provided on the axial outside of the wheel mounting tube, a brake disk mounted to the disk holding cylinder, and a brake device for applying braking to the brake disk. The disk holding cylinder is configured by a cylindrical body to be mounted to the wheel mounting tube and a plurality of disk mounting legs provided on the cylindrical body. A plurality of U-shaped projections are provided on the outer periphery side of the brake disk at positions corresponding to the respective disk mounting legs. A recessed groove which fits on the disk mounting leg so as to hold a distal end thereof is provided in each of the U-shaped projections.

Abstract: In order to recover high-quality scandium from nickel oxide ores efficiently, this method comprises: a step (S1) for feeding Ni oxide ores and sulfuric acid into a pressure vessel, and subjecting the mixture to solid-liquid separation to form a leachate and a leach residue; a step (S2) for adding a neutralizing agent to the leachate, and thus forming a neutralization sediment and a post-neutralization fluid; a step (S3) for adding a sulfurizing agent to the post-neutralization fluid, and separating the obtained mixture into Ni sulfide and a post-sulfurization fluid; a step (S4) for bringing the post-sulfurization fluid into contact with a chelating resin, making Sc adsorbed on the chelating resin, and forming an Sc eluent; a step (S6) for bringing the Sc eluent into contact with an extracting agent, adding a back-extraction agent to the extract, and forming back-extracted matter; and a step (S8) for roasting the back-extracted matter, and forming Sc oxide.

Abstract: The object of the present invention is to provide a method for recovering a rare earth element, which is capable of efficiently recovering a rare earth element with high recovery rate without using any expensive chemicals, solvents or the like. In the present invention, a water-soluble salt other than sulfate ions is allowed to coexist with an aqueous solution that contains a rare earth element, and then an alkali metal sulfate is added to the aqueous solution, thereby producing a precipitate of a double sulfate of the rare earth element.

Abstract: Provided are an impurity-element removing method for selectively removing magnesium from a nickel-containing solution, and a method for producing high-purity nickel sulfate using the impurity-element removing method.

Abstract: The present invention provides a valuable metal leaching method and a valuable metal collection method, in each of which valuable metals can be leached efficiently, the amount of a reducing agent used can be reduced, and cost reduction can be achieved. In the present invention, a positive electrode material is immersed in an acidic solution together with a metal having a lower reduction potential than a reduction potential of hydrogen, whereby valuable metals are leached out from a positive-electrode active substance.

Abstract: The present invention aims at improving a recovery rate of a positive-pole active substance and preventing a recovery loss of valuable metals when a positive-pole active substance is separated from a lithium ion battery. In the present invention, a material resulting from battery dismantling obtained by dismantling a lithium ion battery is stirred using a surfactant solution, whereby a positive-pole active substance is separated from a positive-electrode substrate. Also, it is preferable that an alkaline solution is added to a positive-electrode material of a material resulting from battery dismantling, thereby dissolving a positive-electrode substrate to which a positive-pole active substance adheres to obtain a slurry containing the positive-pole active substance, and a surfactant solution is added to the slurry to disperse the positive-pole active substance in the slurry, whereby the positive-pole active substance is separated from the alkaline solution.

Abstract: A traveling drive device for a dump truck is provided with an axle housing mounted to a vehicle body, a wheel mounting tube rotatably provided on the outer periphery side of the axle housing, a disk holding cylinder provided on the axial outside of the wheel mounting tube, a brake disk mounted to the disk holding cylinder, and a brake device for applying braking to the brake disk. The disk holding cylinder is configured by a cylindrical body to be mounted to the wheel mounting tube and a plurality of disk mounting legs provided on the cylindrical body. A plurality of U-shaped projections are provided on the outer periphery side of the brake disk at positions corresponding to the respective disk mounting legs. A recessed groove which fits on the disk mounting leg so as to hold a distal end thereof is provided in each of the U-shaped projections.

Abstract: The object of the present invention is to provide a method for recovering a rare earth element, which is capable of efficiently recovering a rare earth element with high recovery rate without using any expensive chemicals, solvents or the like. In the present invention, a water-soluble salt other than sulfate ions is allowed to coexist with an aqueous solution that contains a rare earth element, and then an alkali metal sulfate is added to the aqueous solution, thereby producing a precipitate of a double sulfate of the rare earth element.