A method for the precipitation of rare earth sulphate, the method including subjecting a crude rare earth sulphate solution to precipitation in the presence of a water soluble, volatile, organic compound to produce a rare earth sulphate precipitate and an acidic supernatant. The organic compound is preferably selected from the group consisting of methanol, ethanol, iso-propanol, tert-butanol, acetone or mixtures thereof, and is preferably methanol. Preferably, the organic compound is used in the precipitation at a weight ratio of between 0.25:1 to 1.5:1, and preferably 0.5:to 1.25:1, with the crude sulphate solution.

A method for the precipitation of rare earth sulphate, the method including subjecting a crude rare earth sulphate solution to precipitation in the presence of a water soluble, volatile, organic compound to produce a rare earth sulphate precipitate and an acidic supernatant. The organic compound is preferably selected from the group consisting of methanol, ethanol, iso-propanol, tert-butanol, acetone or mixtures thereof, and is preferably methanol. Preferably, the organic compound is used in the precipitation at a weight ratio of between 0.25:1 to 1.5:1, and preferably 0.5:to 1.25:1, with the crude sulphate solution.

A method of processing a purified rare earth sulphate solution, the method including the steps of: contacting the purified rare earth sulphate solution with sodium hydroxide to precipitate rare earths as rare earth hydroxide, including the addition of an oxidant to oxidise cerium contained in the rare earth hydroxide precipitate; and selectively leaching the rare earth hydroxide precipitate with hydrochloric acid to form a rare earth chloride solution and a residue.

Provided is a method for obtaining high-purity scandium oxide efficiently from a solution containing scandium. The method for producing high-purity scandium oxide of the present invention has a first firing step S12 for subjecting a solution containing scandium to oxalation treatment using oxalic acid and firing the obtained crystals of scandium oxalate at a temperature of 400 to 600° C., inclusive, a dissolution step S13 for dissolving the scandium compound obtained by firing in one or more solutions selected from hydrochloric acid and nitric acid to obtain a solution, a reprecipitation step S14 for subjecting the solution to oxalation treatment using oxalic acid and generating a reprecipitate of scandium oxalate, and a second firing step S15 for firing the reprecipitate of obtained scandium oxalate to obtain scandium oxide.

A binder for use in leaching a heap of a low-permeability ore containing at least one of the following: copper ore, copper/cobalt ore, nickel laterite ore and uranium ore, wherein the binder comprises an acid-proof cement formed by modifying ordinary Portland cement (OPC) with a supplementary cementitious material (SCM).

A binder for use in leaching a heap of a low-permeability ore containing at least one of the following: copper ore, copper/cobalt ore, nickel laterite ore and uranium ore, wherein the binder comprises an acid-proof cement formed by modifying ordinary Portland cement (OPC) with a supplementary cementitious material (SCM).

Provided is a method for obtaining high-purity scandium oxide efficiently from a solution containing scandium. The method for producing high-purity scandium oxide of the present invention has a first firing step S12 for subjecting a solution containing scandium to oxalation treatment using oxalic acid and firing the obtained crystals of scandium oxalate at a temperature of 400 to 600 C., inclusive, a dissolution step S13 for dissolving the scandium compound obtained by firing in one or more solutions selected from hydrochloric acid and nitric acid to obtain a solution, a reprecipitation step S14 for subjecting the solution to oxalation treatment using oxalic acid and generating a reprecipitate of scandium oxalate, and a second firing step S15 for firing the reprecipitate of obtained scandium oxalate to obtain scandium oxide.

A method for the precipitation of rare earth sulphate, the method including subjecting a crude rare earth sulphate solution to precipitation in the presence of a water soluble, volatile, organic compound to produce a rare earth sulphate precipitate and an acidic supernatant. The organic compound is preferably selected from the group consisting of methanol, ethanol, iso-propanol, tert-butanol, acetone or mixtures thereof, and is preferably methanol. Preferably, the organic compound is used in the precipitation at a weight ratio of between 0.25:1 to 1.5:1, and preferably 0.5:to 1.25:1, with the crude sulphate solution.

A method for the precipitation of rare earth sulphate, the method including subjecting a crude rare earth sulphate solution to precipitation in the presence of a water soluble, volatile, organic compound to produce a rare earth sulphate precipitate and an acidic supernatant. The organic compound is preferably selected from the group consisting of methanol, ethanol, iso-propanol, tert-butanol, acetone or mixtures thereof, and is preferably methanol. Preferably, the organic compound is used in the precipitation at a weight ratio of between 0.25:1 to 1.5:1, and preferably 0.5:to 1.25:1, with the crude sulphate solution.

The disclosure discloses cerium sulfate chelated sulfur dioxide, a preparation method and a use thereof. The cerium sulfate chelated sulfur dioxide has a molecular formula of Ce[SO4][SO2].2H2O. It is a white crystal and the preparation method thereof may comprise the following steps: adding anhydrous cerium sulfate to dilute sulfuric acid with stirring for dissolvation; adding a solvent followed by refluxing at 45-50 C. for 2.0-2.5 h; heating the reaction product to remove the solvent, cooling to 20 C. or lower, and adding dilute sulfuric acid to allow precipitation of all crystals; cooling down the product followed by suction filtration, washing the obtained crystals by the solvent, so that crude cerium sulfate chelated sulfur dioxide can be obtained. The solubility of the cerium sulfate chelated sulfur dioxide of the disclosure has been significantly improved compared to the anhydrous cerium sulfate. The obtained solution is colorless and transparent, so that the cerium sulfate chelated sulfur dioxide can be used as a better titrant with wide application and supreme performance.