A study of dissolving treatment of covered material on metal surface

금속표면 피복물질의 분해처리에 관한 연구

  • Lee, Cheal-Gyu (Department of environmental engineering, Chongju University) ;
  • Kim, Moon-Chan (Department of environmental engineering, Chongju University)
  • 이철규 (청주대학교 환경공학과) ;
  • 김문찬 (청주대학교 환경공학과)
  • Received : 2004.09.30
  • Accepted : 2005.01.25
  • Published : 2005.04.25


This study reports on the efficiency of cleaning enameled magnet wire using a sulfuric acid $H_2SO_4$ and removal of dissolved organic material using hydrogen peroxide $H_2O_2$ and nitric acid $HNO_3$ at $80^{\circ}C$. The method involves the addition of pure $H_2SO_4$ and $H_2O_2$ or $HNO_3$. Layers of enameled organic material were dissolved by 90% $H_2SO_4$ and the solution was maintained as 35% $H_2O_2$ or 60% $HNO_3$. $H_2O_2$ content in aqueous $H_2O_2$ was maintained as 8.8 : 1.0. An initial concentration of $H_2SO_4$ in dissolution conditions was accomplished within 15 min, with a stripping time of about 2 h. The concentrations of $H_2O_2$ and $HNO_3$ in the processing bath were relatively low, but sufficient enough to produce an effective amount of power in the bath for the removal of the enamel material. The cleaning effect of enameled organic material involves the dehydration by $H_2SO_4$ and the oxidation by $H_2O_2$ or $HNO_3$.


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