Separation of Non-Metallic Components in Waste Printed Circuit Boards (WPCBs) using Organic Solvent and Potassium Phosphate Solution

유기용매와 인산칼륨 용액을 이용한 폐 인쇄회로기판에서 비금속성분의 분리

  • Lee, Jae-Cheon (Mineral Resource Divisionn, Korea Institute of Geoscience and Mineral Resources) ;
  • Jeong, Jin Ki (Mineral Resource Divisionn, Korea Institute of Geoscience and Mineral Resources) ;
  • Kim, Jong Seok (School of Chemical Engineering, Chonbuk National University)
  • 이재천 (한국지질자원연구원 광물연구본부) ;
  • 정진기 (한국지질자원연구원 광물연구본부) ;
  • 김종석 (전북대학교 화학공학부)
  • Published : 2012.08.10


Waste printed circuit boards (WPCBs) contain valuable metals such as Cu, Ni, Au, Ag, and Pd. For an effective recycling of WPCBs, it is essential to recover the valuable metals. In recent years, recycling processes have come to be necessary for separating noble metals from WPCBs due to an increasing amount of electronic device wastes. However, it is well known that glass reinforced epoxy resins in the WPCBs are difficult materials to separate into elemental components, namely metals, glass fibers and epoxy resins in the chemical recycling process. $K_3PO_4$ as a catalyst in dimethylformamide (DMF) and N-Methyl-2-pyrrolidone (NMP) was used to depolymerize epoxy resins for recovering metallic and non-metallic components from WPCBs. Reactions of WPCBs were carried out at temperatures $160{\sim}200^{\circ}C$ for 2~12 h. The recycled glass fiber from WPCBs was analyzed by thermogravimetric analyzer (TGA) and evaluated the degree of solubility of the epoxy resin for separation efficiencies of the WPCBs.


  1. J. M. Yoo, J. K. Jeong, K. K. Yoo, J. C. Lee, and W. B. Kim, Wast. Manage., 29, 1132 (2009).
  2. S. H. Lee and Y. M. Jo, Korean Indus. Chem. News, 13, 2 (2010).
  3. J. C. Lee, H. T. Song, and J. M. Yoo, Resour. Conserv. Recy., 50, 380 (2007).
  4. M. S. Kim, J. C. Lee, J. K. Jeong, B. S. Kim, and E. Y. Kim, J. Kor. Inst. Resour. Recy., 14, 45 (2005).
  5. S. Zang, E. Forssberg, B. Arvidson, and W. Moss, Resour. Conserv. Recy., 23, 225 (1998).
  6. W. J. Hall and P. T. Williams, Resour. Conserv. Recy., 51, 691 (2007).
  7. J. Guo, J. Li, Q. Rao, and Z. Xu, Environ. Sci. Technol., 42, 624 (2008).
  8. W. J. Hall, N. Miskolczi, J. Onwudili, and P. T. Williams., Energy Fuels, 22, 1691 (2008).
  9. Y. J. Park and D. J. Fray, J. Hazard. Mater., 164, 1152 (2009).
  10. E. J. Kelly, Base Material Components, in Printed Circuits Handbook, C. F. Coombs, Ed, McGraw-Hill, New York, Vol 1, Chap. 7 (2008).
  11. W. Dang, M. Kubouchi, H. Sembokuyu, and K. Tsuda, Polymer, 46, 1905 (2005).
  12. M. Goto, M. Sasaki, and T. Hirose, J. Mater. Sci., 41, 1509 (2006).
  13. M. Goto, J. Supercrit. Fluids, 47, 500 (2009).
  14. D. Braun, W. Gentzkow, and A. P. Rudolf, Polym. Degrad. Stabil., 74, 25 (2001).
  15. Y. Sato, Y. Kondo, K. Tsujita, and N. Kawai, Polym. Degrad. Stabil., 89, 317 (2005).
  16. C. Reichardt, Solvents and Solvents Effect in Organic Chemistry, 237, Wiley-VCH, New York (1988).
  17. H. Shih and A. Reister, Macromolecules, 30, 4353 (1997).
  18. F. A. Carey and R. J. Sundberg, Advanced Organic Chemistry, Part A: Structure and Mechanisms, 389, Springer, New York (2008).
  19. C. R. Moon, B. R. Bang, W. J. Choi, G. H. Kang, and S. Y. Park, Polymer Testing, 24, 376 (2005).