7 results about "Ammonium perrhenate" patented technology

This invention belongs to the field of metal ingot preparation technology, specifically relating to a high-purity rhenium ingot and its preparation method. Using ammonium perrhenate solution as raw material, this invention directly generates elemental rhenium and rhenium oxides of different valence states through electrodeposition without complex pretreatment. The mixture is then crushed and fed into a transferred arc hydrogen plasma reaction zone, where the rhenium oxides of different valence states are rapidly reduced to rhenium powder under the high temperature and high energy environment of the hydrogen plasma. The rhenium powder and elemental rhenium fall into a water-cooled copper crucible, where they are continuously heated and melted by the transferred arc hydrogen plasma to form liquid rhenium. Unreacted rhenium oxides continue to be reduced in the liquid rhenium pool to ensure complete reduction. Finally, the liquid rhenium is cooled and solidified to obtain a high-purity rhenium ingot. This invention integrates the reduction and melting processes, resulting in a simple and efficient process that effectively avoids the introduction of impurities. The prepared rhenium ingot has a purity ≥99.99%, high density, and uniform composition, making it widely applicable in high-end fields such as aerospace, nuclear energy, and electronics.

This invention belongs to the field of metallurgical technology, and specifically relates to a method for efficiently extracting rhenium from rhenium-containing waste. The method includes the following steps: pulverizing and sieving the raw material, adding a purification reagent to remove impurities, followed by electrolytic dissolution, evaporating and concentrating the resulting solution, separating it by resin adsorption, eluting with an eluent, purifying by recrystallization, and finally obtaining high-purity rhenium powder by hydrogen reduction. The method provided by this invention effectively removes impurity ions from the waste by introducing a purification reagent, and further utilizes a cation exchange resin to adsorb and separate residual trace metal ions in the solution, thereby avoiding the impact of impurities on the purity of subsequent ammonium perrhenate and rhenium powder. This method has a simple process flow, is highly operable, has a wide range of applications, and has minimal environmental impact, showing promising application prospects.

This invention discloses a combined pyrometallurgical-hydrometallurgical cascade separation method for arsenic-containing sludge from copper smelting, relating to the field of solid waste treatment technology. The method first involves low-temperature roasting of the arsenic-containing sludge at 300-600℃ in a reducing atmosphere to achieve preferential volatilization and recovery of arsenic, while copper and rhenium are retained in the roasted sludge. Next, the roasted sludge is subjected to pressure oxidative leaching, with copper and rhenium entering the leachate, and sulfur being enriched and recovered as elemental. Subsequently, arsenic is precipitated as stable arsenic crystals through ternary coupling control of redox potential, pH, and temperature. After deep removal of residual arsenic using barium / lead salts, rhenium is extracted using a co-extraction system to prepare ammonium perrhenate. Finally, copper is recovered from the raffinate by displacement or electrodeposition. This method can efficiently separate arsenic, sulfur, copper, and rhenium, with a sulfur recovery rate ≥92%, arsenic resource recovery rate ≥99%, rhenium recovery rate ≥92%, copper recovery rate ≥95%, solid waste reduction ≥80%, and no secondary pollution. It is suitable for the resource-based treatment of arsenic-containing sludge from copper smelting.

This invention discloses a method for recovering tungsten and rhenium from tungsten-rhenium alloy waste, belonging to the field of waste metal recycling technology. The method includes: leaching pretreated tungsten-rhenium alloy waste by heating and stirring with a mixed solution of dilute hydrochloric acid and hydrogen peroxide, converting tungsten and rhenium into tungstate ions and perrhenate ions respectively into the solution; then, rapid acidification by quantitatively adding concentrated hydrochloric acid, causing tungsten to precipitate as crystalline tungstic acid; filtering to obtain a crystalline tungstic acid filter cake and a rhenium-containing filtrate; adsorbing the rhenium-containing filtrate through an anion exchange resin to load perrhenate ions onto the resin; subsequently eluting with an ammonia solution to obtain an ammonium perrhenate solution; evaporating, concentrating, and crystallizing to obtain ammonium perrhenate crystals; simultaneously washing and drying the tungstic acid filter cake to obtain the tungstic acid product. This invention features a simple process flow, thorough tungsten-rhenium separation, high recovery rate, is green and economical, and can obtain high-purity tungsten and rhenium products.

This invention discloses a method for preparing 4N ammonium permanganate from low-concentration rhenium-containing waste acid, which is divided into a crude refining stage and a refining stage. The crude refining stage includes a rhenium precipitation process, a leaching process, a hydrolysis process, an acidification process, an extraction process, a back-extraction process, and a crystallization process. The refining stage includes a crude ammonium permanganate dissolution process, an ion exchange process, an extraction process, a back-extraction process, a crystallization process, and a nitration-recrystallization process, ultimately obtaining ammonium permanganate with a purity of 99.99%. In the crude refining stage, this invention first prepares 4N ammonium permanganate from low-concentration rhenium-containing waste acid. Rhenium is efficiently and selectively enriched in concentrated waste acid to obtain a 1% grade rhenium precipitate. Then, a weak oxidation leaching process is used to remove impurities from the precipitate, followed by calcium hydroxide hydrolysis, acidification, high-efficiency extraction, back-extraction, and crystallization to obtain a crude ammonium perrhenate product with a grade of ≥99%. In the refining stage, the crude ammonium perrhenate is dissolved a second time, and a resin ion exchange, extraction, back-extraction, and crystallization process is used to obtain a refined ammonium perrhenate with a grade of ≥99.9%. Finally, a nitration-recrystallization process is used to remove impurities from the refined ammonium perrhenate to achieve a 4N grade quality.

The application discloses a preparation method of a W-Re alloy with a crystal boundary irradiation damage alleviating characteristic, and belongs to the technical field of alloy materials. The preparation method of the W-Re alloy comprises the following steps: dissolving ammonium metatungstate, ammonium perrhenate and polyethylene glycol in a citric acid aqueous solution, drying and calcining after sol preparation, and obtaining an oxide precursor powder; reducing the oxide precursor powder in an environment containing hydrogen, and then sintering in a vacuum environment to obtain a target product. The application realizes uniform dispersion of W and Re at a molecular level, Re is completely solid-solved in a W matrix and segregation does not occur, compared with pure W under the same irradiation condition, the helium bubble number density and the crystal boundary swelling rate of the W-Re alloy prepared by the application are both reduced, and the crystal boundary irradiation damage is effectively alleviated. The application provides a new technical scheme for the design of the crystal boundary irradiation damage resistance of a nuclear fusion reactor plasma-facing W alloy.

The application discloses a Re-doped Ti4O7 anode and a preparation method thereof, relates to the technical field of electrochemical technology for repairing polluted water bodies, and comprises the following steps: adding an ammonium perrhenate solution into a tetrabutyl titanate solution, adding an ethanol aqueous solution, continuously stirring, and standing to obtain a gel; grinding the gel into a powder after drying, and calcining to obtain Re-doped TiO2; adding the Re-doped TiO2 and carbon black into anhydrous ethanol, dispersing and ball-milling, vacuum drying, and performing carbon reduction treatment to obtain Re-doped Ti4O7; performing discharge plasma sintering on the Re-doped Ti4O7, naturally cooling, and obtaining the Re-doped Ti4O7 anode; adding modified carbon nanotubes into deionized water, ultrasonic dispersing, adding the Re-doped Ti4O7 anode, vacuum impregnating, drying, heat treating, and obtaining a composite Re-doped Ti4O7 anode.