tantalum niobium separation molten salt

tantalum niobium separation molten salt

Separation of niobium and tantalum - a literature survey

2018-10-11 · SEPARATION OF NIOBIUM AND TANTALUM The present commercial method for the opening of columbite-tantalite ores involves a basic fusion with molten caustic at 650° C. In this process the pulverized ore is fused with caustic soda which converts the tantalum and niobium content of the mineral partly into the form of

Separation of niobium and tantalum by liquid extraction

2020-10-13 · Separation of niobium from other impurities by a second solvent extraction step using an organic solvent. 5. Stripping of the niobium and tantalum from their solvents and regeneration of solvents. The process as outlined above was studied on a small scale and demonstrated on

A review on extractive metallurgy of tantalum and niobium ...

2020-12-1 · The salt is based on methyltrioctylammonium chloride diluted in toluene. Niobium is then selectively stripped out using oxalic acid and nitrate ions, while Ta is stripped by nitric acid. There are two existing methods for the separation of Ta and Nb by solvent extraction, namely collective and

Rare-Earth Halides as Fluxes for the Synthesis of Tantalum ...

1997-2-18 · While investigating the reported superconducting phase of Lu2Cl2C2-x, we discovered a novel synthetic route for making TaC and NbC. TaC and NbC are superconducting refractory carbides with a Tc of 10 and 12 K, respectively. TaC or NbC was initially found as impurity in reactions designed to produce Lu2Cl2C2-x. TaC and NbC can be prepared as single crystals by reacting Ta or Nb and C in

Separation of Niobium and Tantalum Pentafluoride by ...

2016-7-6 · The similarity between Ta and Nb chemistry makes it difficult to find the appropriate reagents and chemical reactions for the separation of the two elements. This study investigated the precipitation behavior of TaF5 and NbF5 with p-phenylenediamine (PPDA). PPDA preferentially precipitated Nb from a 1:1 ratio of NbF5 and TaF5. Niobium recoveries of >80%, and only 4% Ta, were found in the ...

Carbonization of transition metals in molten salts

The carbonization of niobium (Nb) has been systemically investigated in Ar atmosphere and molten salts. The effect of particle size and structure of the starting materials, molten salt medium, and electric field on the formation of NbC was studied to reveal the dynamic barriers in the carbonization process.

Tantalum Processing | TIC - Tantalum-Niobium

Tantalum metal powder, including the precursor to capacitor grade powder, is generally produced by the sodium reduction of the potassium tantalum fluoride in a molten salt system at high temperature. The metal can also be produced by the carbon or

Recovery of scandium from KOH sub-molten salt leaching ...

2019-6-15 · Abstract. A study was carried out for recovery of scandium from KOH sub-molten salt (SMS) leaching cake of fergusonite. Major metals in the cake were rare earths (RE), K, Th, U and Ca, and minor metals were Pb, Nb, Ta, Ti, Fe, Si, Sn, Al, Bi and Mn. Scandium content was about 0.94% in the cake. Experiments for the recovery of scandium involved ...

Separation and recovery of critical metal ions using ionic ...

2016-3-2 · Separation and purification of critical metal ions such as rare-earth elements (REEs), scandium and niobium from their minerals is difficult and often determines if extraction is economically and environmentally feasible. Solvent extraction is a commonly used metal-ion separation process, usually favored because of its simplicity, speed and wide scope, which is why it is often employed for ...

Leaching of niobium and tantalum from a low-grade ore ...

2013-12-5 · niobium–tantalum ores with KOH sub-molten salt was proposed with the objective to eliminate fluorine pollution at the source (Zhou et al., 2003). In this process, the ore is decomposed in concentrated KOH solution (sub-molten salt) at atmospheric pressure, giving about 10% higher decomposition than that for the HF process. However, a large

Separation of niobium and tantalum - a literature survey

2018-10-11 · SEPARATION OF NIOBIUM AND TANTALUM The present commercial method for the opening of columbite-tantalite ores involves a basic fusion with molten caustic at 650° C. In this process the pulverized ore is fused with caustic soda which converts the tantalum and niobium content of the mineral partly into the form of

Separation of niobium and tantalum by liquid extraction

2020-10-13 · Separation of niobium from other impurities by a second solvent extraction step using an organic solvent. 5. Stripping of the niobium and tantalum from their solvents and regeneration of solvents. The process as outlined above was studied on a small scale and demonstrated on

Separation of Niobium and Tantalum Pentafluoride by ...

2016-7-6 · The similarity between Ta and Nb chemistry makes it difficult to find the appropriate reagents and chemical reactions for the separation of the two elements. This study investigated the precipitation behavior of TaF5 and NbF5 with p-phenylenediamine (PPDA). PPDA preferentially precipitated Nb from a 1:1 ratio of NbF5 and TaF5. Niobium recoveries of >80%, and only 4% Ta, were found in the ...

1 L.D. Cunningham, Columbium (Niobium) and Tantalum ...

2016-3-27 · fluotantalate (K-salt), the crystal which was precipitated by potassium fluoride in the separation of salts step, is electrolyzed to yield pure tantalum metal. The pure tantalum met al is then separated from the cathode by pulverizing the cathode and subsequent acid leaching , resulting in a metal solution and the cathode material (usually ...

Leaching of niobium and tantalum from a low-grade ore ...

2013-12-5 · niobium–tantalum ores with KOH sub-molten salt was proposed with the objective to eliminate fluorine pollution at the source (Zhou et al., 2003). In this process, the ore is decomposed in concentrated KOH solution (sub-molten salt) at atmospheric pressure, giving about 10% higher decomposition than that for the HF process. However, a large

Carbonization of transition metals in molten salts

The carbonization of niobium (Nb) has been systemically investigated in Ar atmosphere and molten salts. The effect of particle size and structure of the starting materials, molten salt medium, and electric field on the formation of NbC was studied to reveal the dynamic barriers in the carbonization process.

中国科学院过程工程研究所机构知识库(CAS OpenIR): 机械 ...

2009-5-30 · (2) The apparent reaction kinetics of mechanically activated niobium-tantalum ore with KOH sub-molten salt was studied. The results showed that, after mechanical activation of 15min and 30min, the apparent activation energy for the leaching of niobium decreased from 80.3KJ/mol to 55.7KJ/mol and 43.9KJ/mol, and the apparent reaction order decreased from 2.43 to 1.24 and 0.96.

Tantalum Metal Production Through High-Efficiency ...

2021-3-9 · The electro-calciothermic reduction of tantalum sulfide (TaS2) was applied to open a new pathway for producing high-purity Ta powders applicable for tantalum electrolytic capacitors. The supplied electric charge was varied to electrochemically reduce the sulfide at 900 °C using Ca in molten CaCl2−xCaS (x = 0.1, 0.5 mol%) salts. The cleaner TaS2 could also be prepared via the highly ...

Rare-Earth Halides as Fluxes for the Synthesis of Tantalum ...

1997-2-18 · While investigating the reported superconducting phase of Lu2Cl2C2-x, we discovered a novel synthetic route for making TaC and NbC. TaC and NbC are superconducting refractory carbides with a Tc of 10 and 12 K, respectively. TaC or NbC was initially found as impurity in reactions designed to produce Lu2Cl2C2-x. TaC and NbC can be prepared as single crystals by reacting Ta or Nb and C in

Molten salts chemistry : from lab to applications-西安交通 ...

2014-11-14 · Molten salts and fused media: provide the key properties and thetheory of molten salts, as well as aspects of fused salts chemistry, helping you generate new ideas and applications for fused salts. This book examines how the electrical and thermal properties of molten salts, and generally low vapour pressure, are well adapted to high temperature chemistry, enabling fast reaction rates.

1 L.D. Cunningham, Columbium (Niobium) and Tantalum ...

2016-3-27 · fluotantalate (K-salt), the crystal which was precipitated by potassium fluoride in the separation of salts step, is electrolyzed to yield pure tantalum metal. The pure tantalum met al is then separated from the cathode by pulverizing the cathode and subsequent acid leaching , resulting in a metal solution and the cathode material (usually ...

Separation of Niobium and Tantalum Pentafluoride by ...

2016-7-6 · The similarity between Ta and Nb chemistry makes it difficult to find the appropriate reagents and chemical reactions for the separation of the two elements. This study investigated the precipitation behavior of TaF5 and NbF5 with p-phenylenediamine (PPDA). PPDA preferentially precipitated Nb from a 1:1 ratio of NbF5 and TaF5. Niobium recoveries of >80%, and only 4% Ta, were found in the ...

Tantalum mining technique –blasting, crushing ...

2021-7-15 · The complete separation of tantalum from niobium is achieved by lowering the ionic strength of the acid mixture, causing the niobium to dissolve in the aqueous phase. ... Potassium heptafluorotantalate is converted to metallic tantalum by adding

Recovery of niobium and tantalum by solvent extraction ...

2020-6-5 · 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 ...

Thermodynamics of niobium chlorides and mixtures with ...

Refractory metals and particularly niobium and tantalum are obtained by molten salt electrolysis. Several authors /1–6/ investigated the electrochemical reduction of niobium ions in chloride or chloride + fluoride melts. However the current efficiency during electrolysis

Oxidation of Niobium in the Molten Eutectic NaNO3 —

First and foremost it is concerned with processes of electrochemical oxidation of valve-metals, such as tantalum, aluminium, titanium, niobium [1–3]. Keywords Oxide Film Molten Salt Aqueous Electrolyte Anodic Film Ionic Current Density

8. FLUORINE CHEMISTRY IN THE PROCESSING OF

Tantalum powder is produced by reduction of potassium heptafluorotantalate, K2TaF7, dissolved in a molten mixture of alkali halides. The reduction is performed at high temperatures using molten ...

Extractive Metallurgy of Tantalum - ResearchGate

The separation of tantalum from niobium formerly performed by fractional crystallization (Rockenbauer, 1984) is now largely performed in chemical and metallurgical industries by solvent extraction ...

Rare-Earth Halides as Fluxes for the Synthesis of Tantalum ...

1997-2-18 · While investigating the reported superconducting phase of Lu2Cl2C2-x, we discovered a novel synthetic route for making TaC and NbC. TaC and NbC are superconducting refractory carbides with a Tc of 10 and 12 K, respectively. TaC or NbC was initially found as impurity in reactions designed to produce Lu2Cl2C2-x. TaC and NbC can be prepared as single crystals by reacting Ta or Nb and C in

Molten salts chemistry : from lab to applications-西安交通 ...

2014-11-14 · Molten salts and fused media: provide the key properties and thetheory of molten salts, as well as aspects of fused salts chemistry, helping you generate new ideas and applications for fused salts. This book examines how the electrical and thermal properties of molten salts, and generally low vapour pressure, are well adapted to high temperature chemistry, enabling fast reaction rates.