China
Africa
Explore chapters and articles related to this topic
Magnetic separation of tantalum ore
Published in Vladimir Litvinenko, Innovation-Based Development of the Mineral Resources Sector: Challenges and Prospects, 2018
Holger Lieberwirth, Filipp Zolotarev, Tim Hühnerfürst
The main ore mineral for tantalum extraction is columbite-tantalite (coltan). Coltan is a heavy mineral with density varying between 5.15 g/cm3 and 8.20 g/cm3 due to variations in its chemical composition. For such minerals, the principal technologies for tantalum- bearing concentrate recovery rely on gravitational methods (Foord, 1982; Cerny and Ercit, 1989; Habashi, 1997). However, concentrates with complex mineral compositions require additional advanced schemes�such as floatation and acid treatment�together with gravitational and electrostatic processing methods to produce high-grade concentrates (Agulyansky, 2004; Emsley, 2001). In the case of concentrates containing magnetic minerals, the preferred method for further beneficiation is magnetic separation. Against this background, the focus of the investigations presented in this paper is to evaluate the benefits of magnetic separation of a low-grade tantalum tailings material and to develop a model to predict the recovery of the valuable component. In this context, dry and wet magnetic separations were investigated to establish parameters for optimized tantalum recovery.
Vanadium and Chromium Groups
Published in Brian D. Fath, Sven E. Jørgensen, Megan Cole, Managing Global Resources and Universal Processes, 2020
All the transition elements of the vanadium group have odd atomic numbers, which could explain their low cosmic and terrestrial abundances compared to those of the titanium (Group 4) and chromium group elements.[2] This also resulted in the presence of only one stable naturally occurring isotope of each of these elements. Vanadium (V) is the 19th most abundant element in the Earth’s crust. The ores that contain vanadium include patronite (VS4), vanadinite [Pb5(VO4)3Cl], dechenite [PbZn(VO4,AsO4)OH], descloizite [Pb(Zn, Cu)(VO4)OH], pucherite (BiVO4), roscoelite (mica containing V), and volborthite [Cu3V2O7(OH)2·2H2O].[3,4] Vanadium (primarily as VO−3) is commonly found in admixture with many minerals such as carnotite K2(UO2)2(VO4)2. Niobium (Nb) and tantalum (Ta) do not occur naturally as free metals but are commonly found together in nature at trace concentrations as iron niobate [(Fe, Mn) (NbO3)2] and iron tantalate [(Fe, Mn)(TaO3)2] in the form of niobite and tantalite minerals, respectively.[5] Large deposits of Nb have been found associated with carbonatites (carbonsilicate rocks) in the form of pyrochlore [(Na, Ca)2Nb2O6(OH, F)].[6]
Kinetics and mechanism of low-temperature aluminothermic reduction of manganese tantalate
Published in Canadian Metallurgical Quarterly, 2022
Alexander Klyushnikov, Roza Gulyaeva, Sofia Petrova, Lyudmila Udoeva
Tantalum is a rare refractory metal with high strength and plastic characteristics that have led to its widespread use in many areas of industry [1]. The majority of tantalum produced is used in electric vacuum and chemical engineering, in the production of electrolytic capacitors, hard and heat-resistant alloys [1, 2]. Common natural sources of tantalum include ores containing minerals of the tantalo-niobates group, which are isomorphic series of complex oxides with the general formula (Fe,Mn)(Nb,Ta)2O6. Depending on the predominance of niobium or tantalum, the mineral is called columbite or tantalite. Tantalum production from such ores is possible according to a scheme that includes [1–5] gravity concentration, acid leaching of concentrates with the transfer of niobium and tantalum to a solution, extraction separation of niobium and tantalum, aluminothermic reduction of Ta2O5 with alloying additives of manganese or iron (in the form of metals or oxides), vacuum heating and electron-beam remelting of Ta–Al–Mn or Ta–Al–Fe alloys to obtain pure tantalum. At the Ta2O5 reduction stage, the addition of alloying additives and excess aluminium to the batch mixture reduces the melting points of the alloy and slag and contributes to their effective separation in the liquid phase [3]. At the same time, manganese and iron are initially present in tantalite (columbite), so it is advisable to exclude hydrometallurgical operations from the process flowsheet and obtain alloys of the Ta–Nb–Al–Mn–Fe system by direct aluminothermic reduction of tantalum-containing concentrates.
Evaluation of mining and mineral processing methods’ impact on tantalite concentrate in Kenticha open pit mine, southern Ethiopia
Published in Applied Earth Science, 2020
Weldegebrial Haile, Bheemalingeswara Konka, Zerihun Desta
Granitic pegmatite hosted tantalite deposit at Kenticha is being mined by an open pit mining method. Currently, loose and medium grade weathered ore is under mining without proper bench design. This led to unsystematic extraction of ore, mainly high-grade ore. Dilution during mining is expected to be about 5% which is not considered high. But, the loss in the tailing is 13.1 g per 30 kg. This is significant when related to 1199.5 t tailing produced per day. Ore loss may be minimized by improving the operating systems in the processing plant.