44results about "Rare earth metal sulfates" patented technology

Provided are a rare earth nano phosphor and a method of preparing a rare earth nano phosphor, the method includes: (a) synthesis of rare earth nano phosphor precursor particles by radiating microwave energy to a solvent where rare earth metal compounds are dissolved; and (b) sintering of inorganic salt and the rare earth nano phosphor precursor mixture.

The invention relates to preparation methods of rare earth layered hydroxide nanosheets and rare earth layered hydroxide nanosheet sol. The preparation method of the nanosheets comprises the followingsteps: preparing a lanthanum nitrate solution with a corresponding concentration, dissolving ammonium sulfate particles into the lanthanum nitrate solution according to a proportion so as to form a mixed solution, adjusting the pH of the mixed solution to 6-10, and continuously stirring to obtain uniform suspension; carrying out a reaction to obtain a product, immediately carrying out centrifugalseparation on the product, and drying to obtain the rare earth layered hydroxide La2(OH)4SO4.nH2O nanosheets. The rare earth layered hydroxide nanosheet sol is prepared by putting the prepared nanosheets into a formamide solution, carrying out ultrasonic centrifugal treatment, and then taking the supernatant. According to the preparation method, the rare earth layered hydroxide La2(OH)4SO4.nH2O nanosheets can be prepared in one step by using an ice-bath method, so that the problem that in the prior art, the compounds cannot be prepared into single-layer nanosheets by using the conventional intercalation-stripping method can be solved; furthermore, the preparation methods are simple in process and convenient to operate, and can realize mass production; the corresponding nanosheet sol is good in stability and material-saving.

The invention relates to a method for treating rare-earth-containing low-grade fluorite minerals, and belongs to the field of hydrometallurgy. The rare-earth-containing low-grade fluorite minerals areused as a target, and provides a method for performing program temperature control segmented slurry decomposition treatment by adopting an absolute excess sulfuric acid solution, a low-temperature section is controlled to preferentially decompose the fluorite minerals, then raising the temperature to decompose the rare earth minerals. The hydrofluoric acid is recycled from tail gas, the reacted acid leaching slag is leached with water to obtain the rare earth, neutralization and thorium removal are carried out to recover the rare earth and the gypsum which is reach the radioactive standard, and the acid leaching solution is used for circularly decomposing the new fluorite minerals after supplementing sulfuric acid. According to the method for treating rare-earth-containing low-grade fluorite minerals, CaF2 and fluorine-carbon cerium ore in the rare-earth-containing low-grade fluorite minerals reach a relatively high decomposition rate through the program temperature control slurryingreaction, the consumption of sulfuric acid is low, the purity of the hydrofluoric acid recovered from the tail gas is high, hydrofluoric acid, gypsum and a sulfuric acid rare-earth solution are obtained, the comprehensively utilize of fluorine, calcium and rare earth resources in the rare-earth-containing low-grade fluorite minerals is realized, The whole process has no three-waste pollution and is clean and environment-friendly.

The invention discloses a comprehensive utilization method of waste FCCU catalyst. The comprehensive utilization method of waste FCCU catalyst comprises following steps: waste FCCU catalyst is introduced into a reaction vessel, concentrated sulfuric acid with a mass concentration of 98% is added for immersion, hydrogen peroxide and oxalic acid are added for mixing and stirring, and sodium bicarbonate is added, so that the pores on catalyst microspheres are cut through by micro pulse generated in neutralization reaction process of sodium bicarbonate with concentrated sulfuric acid; after reaction, filtering is carried out; an obtained filtrate is delivered through an evaporator for recovery of about 80% sulfuric acid in the filtrate, the left sulfuric acid is stored in the evaporator for mixing with reaction liquid obtained in a next time of reaction, a plurality of evaporative concentration is carried out so as to obtain an acid solution rich in lanthanum and cerium, wherein the concentration of the acid solution is 25%; an obtained filter residue is subjected to water washing acid removing and drying collecting so as to obtain aluminium trioxide and silica powder, an obtained water washing liquid is subjected to evaporative concentration and cooling, and is recycled as water used in water washing acid removing, and a part of the water washing liquid is discharged into a sewagetreatment station for treatment and recycling. The raw materials adopted in the comprehensive utilization method posses no direct toxicity, operation complexity is low, energy consumption is low, recovery rate is high, after waste FCCU catalyst recycling, residual refuse accounts for 0.5% or lower.

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.

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 Sc₂O₃ content therein is least of 15 wt. % (in terms of dry matter), the TiO₂ content not more than 3 wt. % (in terms of dry matter), the ZrO₂ 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)₃ hydroxide with ScOHCO₃×4H₂O. Also provided is a method for producing high-purity scandium oxide, with a purity of approximately 99 wt. %.

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.

The invention discloses a rare earth solution preparation process capable of quickly and efficiently removing acid. The preparation process comprises the following steps: drying and crushing, grinding, dissolving and stirring, stabilizing the solution, carrying out microwave digestion and carrying out double-layer acid removal. According to the rare earth solution preparation process capable of rapidly and efficiently removing acid, rare earth mineral powder is prepared through the processes of drying, crushing and grinding, after the rare earth mineral powder is dissolved through strong acidand stabilized through a metallic soap stabilizer, part of dissolved sample acid is removed through sulfuric acid or perchloric acid by heating, and then residual acid removing is conducted through atemperature-controlled acid removing instrument; with application of the process, the sample dissolving acid in the rare earth solution can be quickly removed, the residue of the sample dissolving acid is effectively reduced, the time of the preparation process flow is shortened, the acid driving efficiency and the preparation efficiency of the rare earth solution are improved and the process is worthy of popularization.

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 invention belongs to the field of preparation of inorganic chemistry, in particular to a pollution-free preparation method of ceric sulfate. The preparation method comprises the following steps: dissolving cerium chloride crystals in deionized water; adding strong alkali into the mixture; after full reaction, carrying out aging, suction filtration and cleaning; adding the obtained filter cakesinto dilute sulfuric acid; heating the mixture to react till the filter cakes are fully dissolved; carrying out cooling, crystallizing and suction filtration; and filtering the filter cakes to obtainsaffron yellow high quality ceric sulfate.

An europium sulfate decomposition method is characterized in that europium sulfate is added to a hydrochloric acid solution according to the 1: (2-6): (1-0.5) mass ratio of the europium sulfate to the hydrochloric acid solution to hydrogen peroxide, and stirring is performed for 10-30 minutes; then the hydrogen peroxide is added, and stirring is performed for 1-5 hours; finally, water is added for dilution according to the (0.5-4):1 mass ratio of the water to the hydrochloric acid solution, filtration is performed, filter residues are returned for re-decomposition treatment, and filtrate is used for crude europium preparation. The europium sulfate decomposition method adopts the hydrogen peroxide to decompose the europium sulfate in the hydrochloric acid solution, replaces a traditional nitric acid or alkali heating decomposition process, reduces the energy consumption and is simple in operation and low in cost.

The invention relates to synthesis and application of a rare earth layered thermocatalytic material, wherein the chemical formula of the rare earth rare earth layered thermocatalytic material is REx(OH)y(SO4)z.nH2O, RE represents rare earth elements, and x, y and z can be integers or fractions. According to the invention, the rare earth layered material has excellent stability and Lewis acidity; alcohol, aldehyde and phenol aromatic compounds are synthesized in one step from ethanol; the rare earth layered thermocatalytic material provided by the invention has excellent thermocatalytic performance, wherein the conversion rate of ethanol is close to 100%, the yield of an aldol condensation product reaches 52%, and the selectivity of aromatic compounds in the aldol condensation product is about 80%; and the ethanol involved in the process can be obtained by biomass fermentation, fossil energy consumption can be avoided, the reaction conditions are mild, and the yield of the target product is relatively high.

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 (2θ) in an X-ray diffraction pattern, which is measured using a copper radioactive ray of λ=1.5418 Å passed through a monochromator.