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The concentration of studied metals in buttermilk in ore regions increased by 5–10 times in comparison with the control zone. When studying W-Mo ore landscapes of the North Caucasus (Tyrnyauz), the tungsten and rhenium were found to be capable of incorporation into the xanthine enzyme fractions (oxidase) in animals.
The final content was 26.1–27.3 g/l and 0.35–0.41 g/l for Re and Mo, respectively. Rhenium was concentrated on the second step up to 18–19 times and in comparison with the initial solutions—up to 366–380 times. The pure perrhenate ammonium salt was recovered from the second eluate by crystallization.
and the rhenium present is volatilized, as rhenium heptoxide (Re 2 O 7 ), and scrubbed with water/dilute sulfuric acid to form perrhenic acid (HReO 4 ) in concentrations of up to 0.25 g/L.
The recovery of rhenium is aided by the concentration of its volatile heptoxide (Re 2 O 7) ... (300 °F) and rapidly at higher temperatures to form the yellow heptoxide, Re 2 O 7. The metal is not soluble in hydrochloric acid and dissolves only slowly in other acids. There is evidence for the existence of rhenium in each of the oxidation states ...
For example, after enrichment of copper and molybdenum ores, rhenium is concentrated in their concentrates. The processing of these concentrates by means of …
Rhenium was discovered in 1925 and it is considered to be an extremely rare metal with unique properties. Despite low rhenium concentration in the earth's crust of about 10 −7 %, it acquired wide industrial application [1,2].World rhenium consumption from primary sources ranges from about 50 to 60 metric tons per year [].About 70% of the …
Rhenium is a valuable metal. Its concentration in the Earth's crust is 1 × 10 −3 ppm (g/t) (RSC Periodic Table, n.d), and it exists in a dispersed state. It is one of the elements with highest melting and boiling points. Rhenium is a unique metal because of these physical properties and excellent mechanical and anti-corrosive properties.
@article{osti_901526, title = {Dissimilar behavior of technetium and rhenium in borosilicatewaste glass as determined by X-ray absorption spectroscopy}, author = {Lukens, Wayne W and McKeown, David A and Buechele, Andrew C and Muller, Isabelle S and Shuh, David K and Pegg, Ian L}, abstractNote = {Technetium-99 is an abundant, …
Although the solubility of rhenium in molybdenum allows for up to approximately 50 wt.% rhenium, the compositions in this present work were selected to study the effects of dilute amounts of rhenium in AM-produced alloys. Specimens were analyzed and compared based on chemical composition, room temperature flexural …
It is known that nickel forms several solid solutions with rhenium at concentrations from 0 to 12 at %. Next comes aa two-phase region from about 12 to 90 at % of rhenium. Thus alloys with 5, 10, and 20 wt % are solid solutions.
Pre-concentration of PGE-Re by cation exchange chromatography Platinum group elements form anionic chloro-complexes and Re forms ReO 4 − in HCl media, which are not retained on the cation-exchange resin [35,36,38,39] and this has been utilized as a means of separating the precious metal ions from their matrix (Supplementary Fig. S2a).
The concentration of rhenium in the sample. was visually assessed by the color intensity of the com ... taining rhenium in the form of anions are. formed. For the extraction of perrhenate ions ...
The degree of extraction of rhenium in the target products is 80–99.5%. The purpose of this article is to study the process of oxidative leaching of lead sludge from copper production in order to effectively extract rhenium into the solution. Lead sludge contains 600–1200 g/t of rhenium and is considered to be an additional source of the ...
According to the phase diagram of metallurgical alloys [23], rhenium forms with cobalt solid solutions in a wide concentration range. The coatings obtained by are melting or powder metallurgy differ greatly from electrodeposited alloys in phase composition and in the uniformity of distribution of elements over the surface and throughout the ...
The present study dealt with the hydrometallurgical dissolution of molybdenum (Mo) and rhenium (Re) along with co-existing metal impurities from the molybdenite roasting flue dust using sulfuric acid as the lixiviant medium. The parametric influence of agitation speed, acid concentration, temperature, time, and pulp density in …
Abstract. The β − emitter, rhenium-188 ( 188 Re), has long been recognized as an attractive candidate for targeted cancer radionuclide therapy (TRNT). This transition metal shares chemical similarities with its congener element technetium, whose nuclear isomer technetium-99m ( 99m Tc) is the current workhorse of diagnostic nuclear medicine.
Recovery of rhenium from aqueous solutions by photoinduced-electron transfer from an electron donor to excited-state ReO 4 − is reported for the first time. Specifically, irradiation of aqueous ReO 4 − in the presence of 2-propanol as the electron donor efficiently decreased the ReO 4 − concentration in the solution and resulted in …
The results of joint uranium and rhenium sorptions from the solutions with strong base anion exchange resin Ambersep A920U (herein after A920), are presented in the paper. Effect of salt form (sulfate, chloride, nitrate, hydroxide), nature of sulfate, nitrate, and chloride containing compounds (acids, their sodium and zinc salts), sodium …
1. Introduction. Rhenium (Re), as a critical refractory metal, is widely used in aerospace superheat alloys [1], [2], petroleum smelting catalysts [3], etc.As a highly dispersed rare metal, natural Re is mostly dispersed in copper rhenium sulfide or molybdenite, with a general Re content of 1–1000 ppm [4], [5].In industrial practice, more …
Rhenium forms three stable oxides, rhenium heptoxide (Re 2O 7), rhenium xide (ReO 3), and rhenium dioxide (ReO ... enriched in black shales, with concentrations ranging from 3 to 1000 μg/g (Liao et al. 2019 and references therein). Rhenium is a redox-sensitive trace metal (RSM). The en-
3.1 Rhenium Concentration and Deposit Type. Of the 731 sample sites in the database, 682 were assigned to one of the 30 deposit type categories shown in Fig. 2.Thirty-one of the remaining deposits belong to unknown types, 11 to districts with multiple undifferentiated mineralization styles, and the remaining seven to categories with fewer …
From Wikipedia, the free encyclopediaRhenium is a chemical element with symbol Re and atomic number 75. It is a silvery-white, heavy, third-row transition metal in group 7 of the …
These elements are both present as oxyanions in seawater at higher concentrations than Re. Rhenium was then eluted with 2 mL 4 N HN03. The resulting solution was evaporated to a small drop at 70-80 under N3, and passed through a second column with 5- 10 of resin to purify Re further and to reduce the small amount of organic …
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WebRhenium (Re), chemical element, a very rare metal of Group 7 (VIIb) of the periodic table and one of the densest elements. Predicted by the Russian …
Rhenium deposition begins at −0.53 V. Concerning this reaction, a stark difference is also observed between the traditional electrolyte and the water-in-salt electrolyte. ... manganese electrodeposited from a deep eutectic solvent containing similarly a high chloride concentration forms a passivating layer at highly negative potentials. 22 ...
Rhenium(V) chloride; CAS Number: 1; EC Number: 237-042-6; Linear Formula: ReCl5; find Sigma-Aldrich-309192 MSDS, related peer-reviewed papers, technical documents, similar products & more at Sigma-Aldrich ... form. crystalline. reaction suitability. reagent type: catalyst core: rhenium. concentration. ... concentration. 50.0 …
Rhenium, having the chemical symbol Re, is a rare metallic element that belongs to the transition metal group in the periodic table of elements. It is a silvery, lustrous metal with …
Rhenium concentration in scrubbed liquor remains significantly less (30–200 mg/L) than Mo(VI) concentration []; however, the high economic value of rhenium over molybdenum is more attractive to the metallurgists in recent time.Flue-dusts' leaching in water/dil. H 2 SO 4 followed by ion exchange and solvent extraction are the major …
The hardness of Re nitrides as a function of N concentration is estimated by recently proposed empirical model 39 with the formula HV = 2.0 ( k2G) 0.585 -3.0, as shown in Figure 4 (f). It can be ...
Rhenium-187 is radioactive. A radioactive isotope is one that breaks apart and gives off some form of radiation. The half life of rhenium-187 is about 100,000,000 years. The half life of a radioactive element is the time it takes for half of a sample of the element to break down. ... The concentration of rhenium in Earth's crust is on the order ...
X-ray tubes, and medical devices [2–4]. Rhenium does not form its own deposits. Increased concentrations of rhenium can be found in copper and molybdenum deposits, and it also occurs as an isomorphic impurity in more than 50 carrier minerals [1,3]. In industry, 80% of sources of rhenium raw materials are molybdenum and copper …
