Mineralogy and chemistry of columbite-tantalite from …
Hydrothermal origin of columbite-tantalite is observed in greisens, expressed by a higher W concentration and coeval or even younger crystallization compared to the associated cassiterite. Fractionation trend in a crystal scale includes an extreme increase in Ta/(Ta + Nb) ratio with little or no change in Mn/(Mn + Fe), mainly …
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Radionuclides and Radiation Exposure in Tantalite …
Because the tantalite-columbite deposits at Kenticha have higher tantalum concentrations than niobium (Ta:Nb is up to 3:1), we will refer to this ore as tantalite. The …
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Effect of surface modification by lead ions on flotation …
When columbite-tantalite was treated with BHA, the concentrations of C1 s and N1 s atomic increased by 2.93 % and 2.07 %, respectively, compared with those of bare columbite-tantalite. Moreover, larger increase by 4.33 % and 6.16 % in the C1 s and N1 s concentration was observed after the Pb 2+ -modified columbite-tantalite surface …
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Zoning in columbite-tantalite crystals from the granitic pegmatites …
The zoning of the columbite-tantalite is related to the complex crystallization history of the pegmatite dikes. The main factors controlling oscillatory zoning are considered to be the growth dynamics of the crystals, the concentration and diffusion of the main elements, and the successive flows of the magma in an intrusion channel.
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Extractive metallurgy of columbite-tantalite ore: A detailed …
The extraction of these two metals from columbite-tantalite ore is based on generic extractive metallurgy. However, the upstream purification of ore and downstream extraction of Ta and Nb remain a ...
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Columbite–Tantalite of the Kester Deposit (Eastern …
The generalized formula of columbite–tantalite of the deposit is (Mn0.61Fe0.34)0.95(Nb1.37Ta0.58Ti0.04W0.03Sn0.01)2.03O6. Columbite–tantalite …
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Effects of columbite/tantalite (COLTAN) mining activities …
The mining of columbite/tantalite (COLTAN) has a negative effect on the different spheres of the environment notably; hydrosphere, lithosphere, and the atmosphere (Eisler 2004). Just like gold mining, COLTAN extraction involves the breaking of crystallographic bond in the mineral ore to get the products in the pure form.
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Tantalum, niobium, thorium and uranium concentrations (in …
In columbite-tantalite ores, Ta and Nb often occur in association with thorium, uranium, titanium, and rare-earth elements (REEs) (Dampare et al., 2005). Thus, these ores can be regarded as ...
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Study on Extraction of Niobium Oxide from Columbite-Tantalite Concentrate
Htwe and Lwin (2008) studied on the extraction of niobium oxide from columbite-tantalite concentrate. With the original Columbitetantalite concentrate containing 19.29% Nb 2 O 5, 9.93% Ta 2 O 5 ...
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Rare earth element geochemistry of columbite-group …
New data on rare earth element (REE) concentrations and distribution patterns of columbite-tantalite minerals from Ta-ore provinces worldwide are presented. The REE geochemistry was studied by laser ablation inductively coupled plasma mass spectrometry (LA-ICP-MS). Five major types of chondrite-normalized REE distribution …
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[PDF] Study on Extraction of Niobium Oxide from Columbite–Tantalite …
The principal objective of this study is to be able to extract niobium oxide from columbite-tantalite concentrate of Thayet Kon Area in Nay Phi Taw. It is recovered from columbite-tantalite concentrate which contains 19.29 % Nb2O5.The recovery of niobium oxide from columbite-tantalite concentrate can be divided into three main sections, namely, …
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Radionuclides and Radiation Exposure in Tantalite Mining …
Because the tantalite-columbite deposits at Kenticha have higher tantalum concentrations than niobium (Ta:Nb is up to 3:1), we will refer to this ore as tantalite. The tantalite production is relatively small, but the reserves are large and estimated at 20,000 tonne of T 2 O 5 and Nb 2 O 5.
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Columbite-tantalite-bearing granitic pegmatites from the …
concentrations of common lead are between 0.02 to 0.7 . ppm (Table 4). ... These compositions are compatible with the mineralizations of apatite, beryl, columbite-tantalite, spodumene, lepidolite ...
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Metallographic and in situ compositional study on columbite–tantalite
Figure 4c, d show a compositional transverse in a regular oscillatory zoned crystal, where Nb and Ta concentrations mirror each other. ... (Ti source) and aplite–pegmatites (Sn source). Columbite–tantalite and ilmenite correlation is relatively poor because columbite–tantalite is a scarce mineral in the primary source. However, …
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COLUMBITE-TANTALITE {COLTAN} MINING IN NIGERIA; THE OPPORTUNITIES
Tantalum is a valuable rare element used in electronics manufacturing while columbite is used in forming alloys that are useful in nuclear, aerospace and gas turbine engineering. Rare-metal pegmatites containing economic concentrations of columbite-tantalite ore minerals (coltan) are widespread in the Pan-African (600±150Ma) basement …
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U-Pb isotopic dating of columbite-tantalite minerals: Development of
The U and Pb concentrations and the U-Pb isotopic ratios of columbite-tantalite were analysed at GFZ German Research Centre for Geosciences (Potsdam), using the analytical procedure described in Romer and Smeds (1996).Samples were crushed and picked under the binocular microscope.
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Study on Extraction of Niobium Oxide from …
Effect of Acid Concentration on Digestion Columbite-Tantalite concentrate from Thayetkon Area, Pyinmana Township, contained 19.29 % Nb2O5. Heavy concentrate contained 5 % columbite- tantalite mineral. Columbite-tantalite mineral was separated from other mineral by Frantz Isodymamie Magnetic separator. After separation,
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4 3 and columbite–tantalite
Columbite–tantalite mineralization is therefore both ... 97 fractionation and typically coupled with increasing concentrations of incompatible elements 98 (Černý and Burt, 1984). However ...
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CAUSTIC FUSION OF COLUMBITE-TANTALITE …
CAUSTIC FUSION OF COLUMBITE-TANTALITE CONCENTRATES WITH SUBSEQUENT SEPARATION OF NIOBIUM AND TANTALUM. United States: N. p., 1956. Web. doi:10.2172/4319208. Copy to clipboard ... In these high concentrations where the activity coefficient is not constant with concentration, the heat of transport is defined based on …
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A review on extractive metallurgy of tantalum and niobium
Tantalite concentration (Küster et al., 2009) Tabba Tabba: Pilabara Minerals: Australia: Pegmatite: 0.318: 0.095 (BRGM, 2012) Abu Dabbab: ... In this case, the first stage is designed to leach out iron, manganese, tin, titanium and silicon and produce columbite and tantalite concentrates which are then subjected to Ta and Nb leaching …
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Rare earth element geochemistry of columbite-group
New data on rare earth element ( REE) concentrations and distribution patterns of columbite-tantalite minerals from Ta-ore provinces worldwide are presented. …
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Mineralogical and physical studies of low-grade
This means that the main mineral with commercial value in the ore-samples is cassiterite associated with particles of columbite-(Fe). The highest concentration of tin oxide 53.44 wt% associated with tantalite-(Mn) (4.59 wt% Ta 2 O 5 and 1.42 wt% MnO) was observed in the concentrate R-KMY Con.
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Experimental studies of Ta 2 O 5 and columbite-tantalite …
The dependence of columbite-tantalite (Nb 2 O 5 -59 wt. %, Ta 2 O 5 -18 wt. %) solubility as a function of solution composition, T, and P has also been investigated. Tantalum and Nb concentrations have the highest values in HF solutions at reduced conditions (up to 10-3 to 10-2 m Ta in 1 m HF).
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A mixed collector system for columbite-tantalite flotation
For all the collector suites, the recoveries of columbite-tantalite are sharply increased with increases in initial collector concentrations below 100 mg/L; beyond this value, increases are slighter. Notably, the recovery percentage is the highest for the BHA–SIBX mixture at a mass ratio of 3:1 as compared to the other collector suites at ...
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Quantitative evaluation of metamictisation of …
Members of the columbite–tantalite solid-solution series are a major mineral resource of Nb and Ta, and have the formula, AB 2 O 6, ... The major–minor-element concentrations and U–Pb isotopic ratios …
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In situ U–Pb isotopic dating of columbite–tantalite …
U and Th concentrations of sample Coltan139 are the highest among our studied samples, ranging from 1856 to 2364 ppm, and from 69.1 to 99.1 ppm, …
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Effects of fluorine on the solubilities of Nb, Ta, Zr and Hf …
The effect of fluorine on the solubilities of Mn-columbite (MnNb 2 O 6), Mn-tantalite (MnTa 2 O 6), zircon (ZrSiO 4) and hafnon (HfSiO 4) were determined in highly fluxed, water-saturated haplogranitic melts at 800 to 1000 °C and 2 kbar. The melt composition corresponds to the intersection of the granite minimum with the …
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Processing of columbite-tantalite ores and concentrates …
Columbite and tantalite, either naturally occurring or synthetically produced as concentrates from tinslag, are digested with hydrofluoric acid at elevated …
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COLUMBITE-TANTALITE-BEARING GRANITIC …
Concentrations of lead are the highest among all fractions of the Seridó columbite–tantalite (0.5 to 40 ppm), and uranium concentrations range from 250 to 9200 ppm (Table 4). The Trigero 1 pegmatite In the …
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Extractive metallurgy of columbite-tantalite ore: A …
Abstract. The increased demand of metals such as tantalum (Ta) and niobium (Nb) reflect the on-going development in modern science, engineering and technology. The extraction of these two metals from columbite-tantalite ore is based on …
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