Resources Recycling (자원리싸이클링)

The Korean Institute of Resources Recycling (한국자원리싸이클링학회)
권호 표지
DOI QR코드

DOI QR Code

Tungsten Recovery from Tungsten Carbide by Alkali Melt followed by Water Leaching

알칼리 용융 및 수 침출을 이용한 탄화텅스텐으로부터 텅스텐 회수

  • Kim, Byoungjin (Dept. of Energy & Resources Engineering, Kangwon National University) ;
  • Kim, Suyun (Dept. of Energy & Resources Engineering, Kangwon National University) ;
  • Lee, Jaeryeong (Dept. of Energy & Resources Engineering, Kangwon National University)
  • 김병진 (강원대학교 자원에너지시스템공학과) ;
  • 김수윤 (강원대학교 자원에너지시스템공학과) ;
  • 이재령 (강원대학교 자원에너지시스템공학과)
  • Received : 2017.11.10
  • Accepted : 2017.11.22
  • Published : 2017.12.31
Download PDF
⟨ Previous Next ⟩

Abstract

Tungsten (W) recovery from tungsten carbide (WC) was researched by alkali melt followed by water leaching. The experiments of alkali melt were carried out with the change of the sort of alkali material, heating temperature, and the heating duration. Water leaching of W was performed in the fixed conditions ($25^{\circ}C$, 2 hr., slurry density: 10 g/L). From the mixture of WC and sodium nitrate ($NaNO_3$) in the molar ratio of 1:2, treated at $400^{\circ}C$ for 6 hours, only 63.3% of W might be leached by water leaching. With the increase of sodium hydroxide (NaOH) as a melting additive, the leachability increased. Finally it reached to 97.8 % with the melted mixture of ($WC:NaNO_3:NaOH$) in the ratio of (1:2:2). This imply that NaOH may play a role as a reaction catalyst by lowering Gibb's free energy for alkali melt reaction for WC.

알칼리 용융법과 수 침출을 이용하여 탄화텅스텐(WC)으로부터 텅스텐(W) 회수에 관한 연구를 실시하였다. 알칼리 용융 처리는 알칼리염의 종류, 용융온도 및 용융시간을 변화시키면서 실시하였으며, 수 침출은 $25^{\circ}C$, 2시간 및 슬러리 농도 10 g/L로 고정하여 실시하였다. 알칼리염으로 질산나트륨($NaNO_3$)만 단독으로 사용한 경우, W의 수 침출율은 63.3%이었지만, 용융 첨가제인 수산화나트륨(NaOH) 혼합량이 증가할수록 침출율은 증가하였으며, 몰비 $WC:NaNO_3:NaOH=1:2:2$로 혼합한 용융물에서는 97.8%까지 증가하였다. NaOH는 용융 반응의 반응열 증가로 인한 반응 촉진제 역할을 한 것으로 판단된다.

Keywords

References

  1. J. R. Lee et al., 2017 : A New Recycling Process for Tungsten Carbide Soft Scrap That Employs a Mechanochemical Reaction with Sodium Hydroxide, Metals, 7(7), pp. 230-238. https://doi.org/10.3390/met7070230
  2. J. W. Song et al., 2012 : Industrial Supply Chain Trend of Domestic Tungsten, J. Kor. Powd. Met. Inst., 19(1), pp. 79-86. https://doi.org/10.4150/KPMI.2012.19.1.079
  3. L. Luo et al., 2004 : Recovery of tungsten and vanadium from tungsten alloy scrap, Hydrometallurgy, 72, pp. 1-8. https://doi.org/10.1016/S0304-386X(03)00121-X
  4. J. A. Kim et al., 2011 : Fundamental Study on Recovery of WC from Hardmetal Sludge by Using Mineral Processing, Materials Transactions, 52(7), pp. 1471-1476. https://doi.org/10.2320/matertrans.M2011029
  5. J. H. Kim et al., 2010 : Recovery of Tungsten from WC-Co Hardmetal Sludge by Aqua regia Treatment, J. of Korean Inst. of Resources Recycling, 19(4), pp. 41-50.
  6. J. R. Lee et al., 2016 : Leaching Behavior of Al, Co and W from the Al-Alloying Treated WC-Co Tool as a New Recycling Process for WC Hard Scrap, Metals, 6(8), pp. 174-183. https://doi.org/10.3390/met6080174
  7. J. K. Jeong et al., 2012 : Trend on the Recycling Technologies for the used Tungsten Carbide (WC) by the Patent and Paper Analysis, J. of Korean Inst. of Resources Recycling, 21(1), pp. 82-92. https://doi.org/10.7844/kirr.2012.21.1.082
  8. Y. Zhang et al., 2010 : Decomposition of chromite ore by oxygen in molten NaOH-$NaNO_3$, Int. J. Miner. Process., 95, pp. 10-17. https://doi.org/10.1016/j.minpro.2010.03.005
  9. D. Wang et al., 2016 : Decomposition Kinetics of Titania Slag in Eutectic NaOH-$NaNO_3$ System, Metall. Mater. Trans. B, 47(1), pp. 666-674. https://doi.org/10.1007/s11663-015-0491-y
  10. B. F. Dmitruk et al., 1997 : Thermodynamics of Tungsten Carbide Decomposition by Molten Salts, Inorg. Mater., 33(9), pp. 1072-1075.
  11. H. R. Kim et al., 2012 : Leaching of Vanadium and Tungsten from Spent SCR Catalysts for De-$NO_x$ by Soda Roasting and Water Leaching Method, J. of Korean Inst. of Resources Recycling, 21(6), pp. 65-73. https://doi.org/10.7844/KIRR.2012.21.6.65