Treatment of Black Dross with Water and NaOH Solution

물과 수산화나트륨용액에 의한 블랙 드로스의 처리

  • Xing, Wei Dong (Department of Advanced Material Science & Engineering, Institute of Rare Metal, Mokpo National University) ;
  • Ahn, Byung Doo (DSLiquid Co., Ltd) ;
  • Lee, Man Seung (Department of Advanced Material Science & Engineering, Institute of Rare Metal, Mokpo National University)
  • Received : 2017.05.08
  • Accepted : 2017.05.26
  • Published : 2017.06.30


Black dross contains metallic aluminium, alumina, silica, MgO, soluble salts together with minor ingredients. Control of silica in black dross is important in transforming the black dross into usable materials. First, most of the soluble salts (KCl and NaCl) in black dross were dissolved in water at reaction temperature of $50^{\circ}C$. Leaching behavior of silica, alumina, MgO and $TiO_2$ from the residue after water treatment was investigated by varying NaOH concentration and reaction temperature. Reaction temperature ($25{\sim}95^{\circ}C$) was favorable to the leaching of alumina but an optimum temperature existed for silica. MgO was not dissolved at all in the NaOH concentration range from 2 to 6 M. At the leaching condition of 5 M NaOH and reaction temperature of $95^{\circ}C$, approximately 80% of alumina and 68% of silica was dissolved.


Supported by : Korea Institute of Energy Technology Evaluation and Planning (KETEP)


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