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.

Disclosed herein are methods, techniques, and processes for enhancing the purity of a mixed rare earth solution. In one embodiment the rare earth mixture may include Lanthanum, Cerium, Praseodymium, Neodymium, Promethium, Samarium, Europium, Gadolinium, Terbium, Dysprosium, Holmium, Erbium, Thulium, Ytterbium, Lutetium, Scandium, and/or Yttrium. In one embodiment, the resin is a chelating resin that interacts poorly with one or more rare earth elements. In one embodiment a rare earth is selectively excluded for example, Lanthanum (sometimes considered a transition metal), Cerium, Praseodymium, Neodymium, Promethium, Samarium, Europium, Gadolinium, Terbium, Dysprosium, Holmium, Erbium, Thulium, Ytterbium, Lutetium, Scandium, and/or Yttrium. In one embodiment, yttrium is selectively excluded from the column.

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.

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.

The invention relates to a method for producing a scandium-containing concentrate from the wastes of alumina production and extracting high-purity scandium oxide from the same. Provided is a method for producing a scandium-containing concentrate from a red mud, wherein the Sc.sub.2O.sub.3 content therein is least of 15 wt. % (in terms of dry matter), the TiO.sub.2 content not more than 3 wt. % (in terms of dry matter), the ZrO.sub.2 content not more than 15 wt. % (in terms of dry matter), and wherein scandium in the concentrate is in form of a mixture of Sc(OH).sub.3 hydroxide with ScOHCO.sub.34H.sub.2O. Also provided is a method for producing high-purity scandium oxide, with a purity of approximately 99 wt. %.

An object of the present invention is to provide an inexpensive and highly safe compound useful as a chemical heat storage material that ensures high reproducibility even in repeated reactions (having high repetition durability), and is capable of reversibly advancing heat storage and heat dissipation even in a relatively low temperature range. The present invention is a hydrate of a rare earth metal sulfate having characteristic peaks at specific diffraction angles (2) in an X-ray diffraction pattern, which is measured using a copper radioactive ray of =1.5418 passed through a monochromator.

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.

In alternative embodiments, the invention provides processes and methods for extracting and recovering rare earth materials from a wet-process phosphoric acid using one or more continuous ion exchange resin systems. In alternative embodiments, the method is particularly suited for use in extracting and recovering multiple rare earth materials present in low concentrations contained in wet-process phosphoric acid.

Mixed rare earth sulfate solutions depleted of cerium may be prepared by mixing a mixed rare earth sulfate solution with a pH adjusting agent comprising a magnesium oxide, and adding a sulfate adjusting agent comprising magnesium sulfate to the mixed rare earth sulfate solution, thereby generating a mixture; adding an oxidizing agent to the mixture thereby generating a slurry comprising insoluble cerium (IV) hydroxide, the oxidizing agent comprising hydrogen peroxide (H.sub.2O.sub.2); and filtering the slurry, thereby generating a cerium depleted mixed rare earth sulfate solution and cerium-rich mixed rare earth solids.

Mixed rare earth sulfate solutions depleted of cerium may be prepared by mixing a mixed rare earth sulfate solution with a pH adjusting agent comprising a magnesium oxide, and adding a sulfate adjusting agent comprising magnesium sulfate to the mixed rare earth sulfate solution, thereby generating a mixture; adding an oxidizing agent to the mixture thereby generating a slurry comprising insoluble cerium (IV) hydroxide, the oxidizing agent comprising hydrogen peroxide (H.sub.2O.sub.2); and filtering the slurry, thereby generating a cerium depleted mixed rare earth sulfate solution and cerium-rich mixed rare earth solids.