These results indicate strong enrichment of rhenium in undegassed arc rocks, and consequently the continental crust, which results in a crustal estimate of ∼ 2 p.p.b. rhenium, as compared to ...

An enrichment recovery method of trace rhenium in an extremely-low-concentration dilute solution, in particular to a method for enriching and recovering the trace rhenium in the extremely-low concentration from an adsorption tail solution obtained by a sandstone-type uranium ore in-situ leaching uranium mining process. Ferric salt FeCl 3 Or Fe 2 (SO 4 ) 2 …

Rhenium concentrations in the bulk, clay and exchangeable fractions of bed sediments of the Chilika were also measured during this study. ... Our study also hints at a gain in Re concentrations in the low saline (<10) region during pre-monsoon season (Fig. 4). This observed Re gain, however, is well within the uncertainty band of the mixing ...

One or two gram aliquots of twelve reference materials with low platinum-group element (PGE) abundances (Ir concentrations ranging from 30 to 510 pg g -1 ) were analysed by isotope dilution ICP-MS using an on-line chromatographic matrix separation after acid digestion in a high pressure asher (HPA-S) to determine the concentrations of Ru, Pd, …

PDF | We present a review of literature on the methods for rhenium determination published from 2000 to 2010. | Find, read and …

of rhenium concentration, isotopes 185 R e a nd 187 Re were selected. The a n alysis w as performed in tw o modes: standard and with using a helium collision cell with kinetic energy discrimination.

Int. J. Electrochem. Sci., Vol. 15, 2020 6770 Our prior studies revealed the multi-step electroreduction mechanism of ReO4-to Re[14], and pointed out the positive role -of high acidity and low ReO4 concentration in electrodepositing metallic rhenium. However, a high ReO4-concentration usually leads to the formation of rhenium oxides[15-16], which ...

The concentration of uranium in the leaching solution is about 50–500 mg/L. At present, ion exchange resin is mainly used to adsorb and recover the low concentration uranium in the leaching solution [6–8]. At the same time, rhenium is widely used in nuclear power, national defense, aerospace and other

Up to a concentration of 41 wt pct Re, the Charpy ductile-to-brittle transition temperature decreased monotonically with increasing rhenium concentration. Consistent with this, bend angles for fracture at T=−100 °C increased monotonically with increasing rhenium concentration. Between 10 and 41 wt pct rhenium, the room-temperature tensile ...

2.1. Batch Solutions. The metal solutions with given concentrations were prepared by dissolving a suitable amount of NaReO 4, CuSO 4, and Na 2 MoO 4 (Sigma Aldrich, analytical grade) in deionized water. Since rhenium is mainly recovered as a byproduct of molybdenum and copper processing, four systems with the following …

Rhenium oxidation states range from −1 to +7, with the most abundant being +7, +6 and +4.9 Rhenium is a soluble element in oxic conditions and …

In the low rhenium concentration range (<5 at.%Re), solute segregation is found to occur in the form of voids decorated by Re atoms. These vacancy-rhenium clusters remain stable over a broad temperature range from 800 K to 1600 K. At lower temperatures, simulations predict the formation of Re-rich rhenium– vacancy

However, owing to the large volume of waste acid and the low concentration of rhenium, the extracting efficiency is relatively limited and the cost rather high.10 Some oxidation leaching methods have also been reported to leach rhenium from arsenic filter cake with low content of rhenium, such as high-pressure oxidation leaching …

Rhenium (Re) and osmium (Os) are both members of the sixth period of the periodic table of elements. While Re has chemical properties similar to molybdenum (Mo), Os is one of the six platinum-group elements (PGEs). Both Re and Os are strongly siderophile and present in minute quantities in terrestrial rocks; their concentrations are extremely low in igneous …

Rhenium concentrations in molybdenite are between 330 and 642 ppm. Four Re–Os analyses of two molybdenite samples from the quartz monzonite and porphyritic quartz monzonite yield a weighted average age of 71.8±0.2 Ma (2σ). ... Total measured osmium and rhenium in blanks for low concentration samples were 1 to 2 pg and 10 to …

A low concentration of rhenium in the extract does not allow the use the method of solid-phase stripping. Calculations showed that rhenium recovery into ammonium perrhenate in this case does not exceed 15–30% of the content in the extract. Therefore rhenium concentration in an extract should be not less than 5 g/dm 3. For …

The rhenium concentration decreased with time during the second irradiation, and the platinum remained very low because it had been mostly removed from the solution as a precipitate during the first irradiation. The results obtained from the first irradiation time of 3 h and the second irradiation time of 12 h are summarized in Table S …

One or two gram aliquots of twelve reference materials with low platinum-group element (PGE) abundances (Ir concentrations ranging from 30 to 510 pg g-1) were analysed by isotope dilution ICP-MS using an on-line chromatographic matrix separation after acid digestion in a high pressure asher (HPA-S) to determine the concentrations of …

the low concentration of rhenium, the extracting efficiency is relatively limited and the cost rather high.10 Some oxidation leaching methods have also been reported to leach rhenium from arsenic filter cake with low content of rhenium, such as high-pressure oxidation leaching and oxidation leaching by oxidant.11 Generally, the high-pressure ...

The main problem associated with rhenium recovery is its low concentration and interference with other ionic constitutes in process solutions, especially with molybdenum. It is known that molybdate and tungstate tend to form large polymeric anions. Their size, or polymerization rate, depends on pH and concentration of the solution.

For instance, Zea mays treated with a low Cd 2+ concentration (5 mg/L Cd 2+) had sparse grana lamellae, reduced layers of grana lamellae in chloroplast.However, at high concentrations (50 mg/L Cd 2+), the chloroplasts membrane system began to collapse, the chloroplasts contracted and a large number of vesicles appeared.

The electroreduction mechanism of ReO 4 − in acidic solution is investigated intensively via experiments and thermodynamic analysis. High acidity and low ReO 4 − concentration are the advantageous conditions to fabricate metallic rhenium, while under other conditions only small amount of rhenium oxides can be obtained. The reduction of …

Use of Dowex 1X8 and AgCl Column.A Dowex 1X8 anion exchanger (Cl-form, 200–400 mesh) with a capacity of 3–5 meq/g (Sigma Chemicals) and extra pure AgCl were used in this method of postelution concentration [].Between 10 and 12 mg of Dowex 1X8 resin was taken in a 2 mL syringe and placed in a polypropylene tube (~8 mm × 1 mm) with a few …

at low rhenium concentrations, the major benefits of rhenium additions are to be found at the highest possible concentration. Savitskii and coworkers (Ref 4) were the first to construct a molybdenum-rhenium phase diagram (Fig. 1 ). The system has a large region for solid solution of rhenium in molybdenum, ex-

In conclusion, we synthesized a new resin LSL-N with N-methylimidazole as the functional group to recover the low concentration rhenium in the roasting leaching solution of molybdenum concentrate. On the one hand, batch adsorption experiments show that the synthesized resin has good adsorption properties for rhenium and molybdenum, …

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 …

Their rhenium concentration cannot be correlated to geographical distribution, geological age, or the geology of the deposit. Within restricted regions, however, pipe deposits are demonstrably lower in rhenium concentration than are vein type occurrences. The hypothesized enhancement of rhenium in molybdenites associated with copper ...

The concentration of Re is too low, and the force between them is weaker, resulting in poorer precipitation effect of Re. In conclusion, the precipitation effect of Re is …

Rhenium is characterized by a high alloy fraction (70%) and a moderate-to-high functional recycling rate. Rhenium's alloy use is entirely in superalloys—high in …

The present invention relates to a kind of methods that low concentration rhenium is recycled in from uranium ore immersion liquid.For rhenium-containing uranium ore rhenium concentration is low in immersion liquid, the problem of enriching and recovering difficulty, selects the anion exchange resin with bifunctional group, and using its distinctive strong …