Recovery of tungsten and vanadium from tungsten alloy scrap

Luo, Lin; Kejun, Liu; Shibayama, Atsushi; Yen, W.T.; Fujita, Toyohisa; Shindo, Osamu; Katai, Akira

doi:10.1016/s0304-386x(03)00121-x

Cited by 63 publications

(18 citation statements)

References 2 publications

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“…Among these, caustic leaching seems to be the best option for the recovery of SCR catalyst, since WO 3 is insoluble in acid. Once in solution, the metals can be isolated in a pure form using established methods, such as selective precipitation [14,15], solvent extraction [16,17], and ion exchange [18,19]. V and W exhibit very similar chemical properties and are produced commercially by relatively similar procedures [20].…”

Section: Introductionmentioning

confidence: 99%

Tungsten Recovery from Spent SCR Catalyst Using Alkaline Leaching and Ion Exchange

Tsai

Shen

2016

Minerals

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Abstract:The recovery of tungsten (W) from a honeycomb-type spent selective catalytic reduction (SCR) catalyst using an alkaline leaching-ion exchange method was investigated. Spent SCR catalyst mainly consists of TiO 2 and other oxides (6.37% W, 1.57% vanadium (V), and 2.81% silicon (Si), etc.). The ground catalyst was leached at the optimal conditions, as follows: NaOH concentration of 0.3 kg/kg of catalyst, pulp density of 3%, leaching temperature of 70 • C, particle size of −74 µm, and leaching time of 30 min. In this study, the leaching rate values of V and W under the above conditions were 87 wt %, and 91 wt %, respectively. The pregnant solution was then passed through a strong base anion exchange resin (Amberlite IRA900). At high pH conditions, the use of strong base anion exchange resin led to selective loading of divalent WO 4 2− from the solution, because the fraction of two adjacent positively-charged sites on the IRA900 resin was higher and separate from the coexisting VO 4 3− . The adsorbed W could then be eluted with 1 M NaCl + 0.5 M NaOH. The final concentrated W solution had 8.4 g/L of W with 98% purity. The application of this process in industry is expected to have an important impact on the recovery of W from secondary sources of these metals.

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Section: Introductionmentioning

confidence: 99%

Tungsten Recovery from Spent SCR Catalyst Using Alkaline Leaching and Ion Exchange

Tsai

Shen

2016

Minerals

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“…Consequently, alternative sources such as low-grade ores, polymetallic ores, industrial wastes, and electronic scraps must be considered. [1][2][3] For an efficient exploitation of these resources, the development of processes that enhance metal extraction is needed. [4] Chlorination and carbochlorination processes are applied in extractive metallurgy for high-value metal extraction from polymetallic or low-grade ores by transforming them into chlorides.…”

Section: Introductionmentioning

confidence: 99%

Intrinsic Kinetics of Chlorination of WO3 Particles With Cl2 Gas Between 973 K and 1223 K (700 °C and 950 °C)

Micco

Bohé

Sohn

2011

Metall Mater Trans B

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Chlorination is one of the methods applied in extractive metallurgy for the treatment of minerals to obtain valuable metals, such as titanium and zirconium. The possibility of applying chlorination metallurgy to other metals such as tungsten was the major aim of this study. The kinetics of the chlorination of tungsten oxide (WO 3 ) particles has been investigated by thermogravimetry between 973 K and 1223 K (700°C and 950°C) and for partial pressures of chlorine ranging from 15 to 70 kPa. The starting temperature for the reaction of WO 3 with chlorine is determined to be about 920 K (647°C). The influence of chlorine diffusion through the bulk gas phase and through the particle interstices in the overall rate was analyzed. In the absence of these two mass-transfer steps, a reaction order of 0.5 with respect to chlorine partial pressure, and an activation energy of 183 kJ/mol were determined. For tungsten oxide particles of less than 50-lm size, a complete rate expression has been obtained.

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“…The pollution legacy caused by W enrichment in some of these mining districts is severe [10,11]. However, it's not just the manufacturing processes that are a cause of concern, leachates from E-waste repositories and recycling sites can also contain considerable amounts of W [12]. Measures to phase out lead in ammunition, has seen W being used as its replacement [13], resulting in a relatively new and poorly characterized exposure source/pathway [1,4,9].…”

Section: Introductionmentioning

confidence: 99%

High-resolution measurement and mapping of tungstate in waters, soils and sediments using the low-disturbance DGT sampling technique

Guan

et al. 2016

Journal of Hazardous Materials

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This manuscript version is made available under the CC-BY-NC-ND 4.0 license (http://creativecommons.org/licenses/by-nc-nd/4.0/), which permits distribution and reproduction for non-commercial purposes, provided the author and source are cited. General rightsCopyright for the publications made accessible via the Queen's University Belfast Research Portal is retained by the author(s) and / or other copyright owners and it is a condition of accessing these publications that users recognise and abide by the legal requirements associated with these rights.Take down policy The Research Portal is Queen's institutional repository that provides access to Queen's research output. Every effort has been made to ensure that content in the Research Portal does not infringe any person's rights, or applicable UK laws. If you discover content in the Research Portal that you believe breaches copyright or violates any law, please contact openaccess@qub.ac.uk. high-resolution W profiling across sedimentwater and hotspotbulk media interfaces from Lake Taihu was obtained using PZ DGT coupled with laser ablation ICPMS measurement, and the apparent diffusion fluxes across the interfaces were calculated using a numerical model. KEY WORDS: diffusive gradients in thin-films (DGT); tungsten; precipitated zirconia (PZ) gel; sub-mm high resolution; hotspotbulk media interface.

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Recovery of tungsten and vanadium from tungsten alloy scrap

Cited by 63 publications

References 2 publications

Tungsten Recovery from Spent SCR Catalyst Using Alkaline Leaching and Ion Exchange

Tungsten Recovery from Spent SCR Catalyst Using Alkaline Leaching and Ion Exchange

Intrinsic Kinetics of Chlorination of WO3 Particles With Cl2 Gas Between 973 K and 1223 K (700 °C and 950 °C)

High-resolution measurement and mapping of tungstate in waters, soils and sediments using the low-disturbance DGT sampling technique

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