7.84 103 mg/kg, which have large recovery value. As the surface area and pore size of the slag are very small, the leaching agent cannot fully penetrate the particles. Various methods of characterization ... The tantalum-niobium slag should be pretreated before the experiments. The samples were dried in a blast drying oven at 50 C for 24 h. …

Demand for niobium and tantalum is increasing exponentially as these are essential ingredients for the manufacture of, among others, capacitors in technological devices and ferroniobium. Mine tailings rich in such elements could constitute an important source of Nb and Ta in the future and alleviate potential supply risks. This paper …

The final concentrate contains 46% tantalum niobium and 5-6% tin, and the recovery rate is 86%. We also use this beneficiation process of tantalum niobium tin ore for our Rwanda customers, 51% …

Introduction Niobium and tantalum primary minerals are naturally occurring complex oxide ores, majorly of low grade deposits with chemical content of mainly Nb 2 …

The final products of the process are niobium oxide and potassium tantalum salts. Niobium oxide has a purity of 98.5% and impurities of Ta, 1.85% as Ta 2 O 5. Tantalum salt, after calcination and purification, has a purity of 97.3% and impurities of Nb 2 O 5, around 1.6%. The limiting factor of the process is the first stripping step, above all ...

Increasing demand for niobium, tantalum, titanium, uranium, thorium and rare earth elements has stressed the importance of developing methods for their recovery and processing into marketable form.

In July, a specialty metals processor in Estonia suspended its niobium and tantalum recovery operations. The company reached its limit for onsite storage of the radioactive tailings that were produced during recovery of niobium and tantalum. The Ministry of Environment of Estonia required the company to have an agreement for offsite storage

Abstract The current hydrometallurgical processes used for niobium and tantalum recovery are operated in strongly acidic and fluoride-containing solutions. To …

In brief, niobium and tantalum are co-extracted into the organic phase, followed by selective stripping of niobium and tantalum subsequently. The process may be improved to reduce the requirement for organic solvents by the introduction of multiple stages for metal recovery which is the focus of this paper.

A study has been carried out on Ta and Nb recovery by a liquid-liquid extraction process using 4-methylacetophenone (4-MAcPh) as the organic phase. The 4-MAcPh was compared to methyl isobutyl ketone (MIBK) with respect to extraction efficiencies (D values) at different concentrations of H2SO4 in the aqueous phase. The results showed a similar extraction …

We propose a novel integrated model for the recovery of tantalum from tantalum-rich waste using a combination of hydrometallurgical and bio-metallurgical processes. To this end, leaching experiments with heterotrophs ( Pseudomonas putida, Bacillus subtilis and Penicillium simplicissimum) were carried out. The heterotrophic …

Niobium and tantalum can exist in several valence states suchas+5,+4,+3,+2andeven+1intheircompounds.However, only Nb(V) and Ta(V) are …

The proposed mechanized techniques were found to increase the efficiency of tin and tantalum recovery from 60.75% to 81.85% and from 22.9% to 48.57%, respectively, and the grades of the tin and ...

Niobium is recycled when niobium-bearing steels and superalloys are recycled, but scrap recovery specifically for niobium is negligible. Niobium and tantalum ores do not pose any special environmental problems, and standard industry-wide safety and environmental precautions during mining and mineral concentration are satisfactory. Tantalum ...

The current hydrometallurgical processes used for niobium and tantalum recovery are operated in strongly acidic and fluoride-containing solutions. To avoid the use of these highly toxic media, a fluoride-free process was developed to recover Nb and Ta from low-grade industrial concentrates.

The recovery of niobium and tantalum from a low-grade niobium–tantalum ore by using highly concentrated caustic potash as an alternative to hydrofluoric acid has been investigated. Experiments ...

The results showed that the tantalum extraction rate and tantalum and niobium separation factors were above 94% and 200, respectively, and the purity of potassium fluotantalate met the ...

The conditions were found for separation of tantalum(V) and niobium(V) from titanium(IV), allowing recovery of 95.7 and 84.1% of tantalum and niobium fluoride complexes, respectively, in one ...

Abstract Niobium (Nb) and Tantalum (Ta) are used to increase materials' mechanical resistance and produce lighter alloys. Worldwide Nb production reached 78 000 t in 2020. ... paper brings the main methods used to extract the Nb and Ta from the primary resources and an overview of Nb and Ta recovery from the slag. This investigation comes as a ...

Introduction. Niobium and tantalum primary minerals are naturally occurring complex oxide ores, majorly of low grade deposits with chemical content of mainly Nb 2 /Ta 2 O 5 and oxides of Fe, Mn, Sn, Ti and other metal oxides. Over the decades, researchers have extensively and consistently investigated the extraction and recovery of Nb and Ta …

The occurrence of niobium minerals is more complex than that of tantalum minerals; thus, a lower recovery for niobium than tantalum may be expected. The main gangue minerals associated with tantalum and niobium minerals include kaolinite, illite, mica, feldspar, quartz, etc. Kaolinite is abundantly present in the ore and can be recycled …

The recovery of niobium and tantalum from a low-grade niobium–tantalum ore by using highly concentrated caustic potash as an alternative to hydrofluoric acid has been investigated. Experiments on the leaching behavior of niobium and tantalum, as well as other associated impurities, such as titanium, iron, manganese, silicon, and aluminum …

The pyrometallurgical methods of the recovery of various critical metals have been established. Certain pyrometallurgical approaches for niobium (Nb) and tantalum (Ta) extraction have been studied and investigated by several researchers. For instance, the conventional reduction of Nb mineral or Nb2O5 to Nb metal has been conducted over the …

The current study focuses on alkali-assisted roasting, dissolution, and recovery of mixed oxides of niobium (Nb) and tantalum (Ta) from ferro-columbite concentrate collected from Jos Plateau in ...

The amount of niobium in these samples was below the economic range of consideration and thus was considered only a byproduct of tantalum recovery. Material was stage ground to minus 0.59 mm and separated into the same three size ranges as used for processing Sample A. Table concentrates from the three respective size ranges were …

The current hydrometallurgical processes used for niobium and tantalum recovery are operated in strongly acidic and fluoride-containing solutions. To avoid the use of these highly toxic media, a ...

The optimum tantalum and niobium recovery rates are 93 and 78 pct, respectively. The results of this research indicate that the leaching of the amorphous tin slag is a structure-sensitive operation.

The current hydrometallurgical processes used for niobium and tantalum recovery are operated in strongly acidic and fluoride-containing solutions. To avoid the use of these highly toxic media, a ...

Niobium and tantalum primary minerals are naturally occurring complex oxide ores, majorly of low grade deposits with chemical content of mainly Nb 2 /Ta 2 O 5 and oxides of Fe, Mn, Sn, Ti and other metal oxides. Over the decades, researchers have extensively and consistently investigated the extraction and recovery of Nb and Ta from …

From an ore that assays 0.5% Nb 2 O 5, a concentrate grade of 49% Nb 2 O 5 at a recovery of 73% was achieved. ... This chapter discusses flotation and beneficiation of tantalum/ niobium ores. There is very little information or literature on flotation properties of tantalum minerals. Also, there are only a few operating plants that treat ...