Clean Technology (청정기술)

The Korean Society of Clean Technology (한국청정기술학회)
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Leaching of Iron and Aluminum from Red Mud and Preparation of Coagulants

적니로부터 철과 알루미늄의 침출 및 응집제의 제조

  • Lee, Jae-Rok (Department of Chemical and Biochemical Engineering, The University of Suwon) ;
  • Hwang, In-Gook (Department of Chemical and Biochemical Engineering, The University of Suwon) ;
  • Bae, Jae-Heum (Department of Chemical and Biochemical Engineering, The University of Suwon)
  • 이재록 (수원대학교 화공생명공학과) ;
  • 황인국 (수원대학교 화공생명공학과) ;
  • 배재흠 (수원대학교 화공생명공학과)
  • Published : 2009.03.31
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Abstract

Red mud is generated as a waste byproduct during the production of aluminum hydroxide/alumina from bauxite ore in the Bayer process. In this study coagulants for wastewater treatment were prepared by leaching iron and aluminum from red mud with hydrochloric acid. The removal efficiency of heavy metal ions by the red mud coagulant increased with increasing the adjusted pH value of the synthetic wastewater. When the red mud coagulant was prepared, the leaching efficiency of Fe decreased with increasing the weight of red mud, while the pH value of the red mud coagulant increased. The solution of the red mud coagulant mixed with water was reacted again with red mud to produce the leached solution, which had higher concentrations of Fe and Al and a higher pH value than the red mud coagulant. Also, its pH value was comparable to that of other coagulants: $FeCl_3$ and $Fe_2(SO_4)_3$.

적니(red mud)는 보오크싸이트로부터 수산화알루미늄/알루미나를 제조하는 Bayer 공정에서 부산물로 발생되는 폐기물이다. 본 연구에서는 적니로부터 철과 알루미늄을 염산으로 침출시켜 폐수처리용 응집제를 제조하였다. 적니응집제를 합성폐수에 투입한 후 조절된 pH가 증가함에 따라 중금속이온 제거율이 증가하였다. 적니응집제 제조 시에 적니의 양이 증가할수록 Fe의 침출효율은 낮아졌으나, 적니응집제의 pH는 적니의 양이 증가할수록 높아졌다. 적니응집제와 물을 혼합한 용액을 다시 적니와 반응시켜 Fe 및 Al의 농도가 더 증가되고, pH가 향상된 침출액을 얻었다. 이 침출액의 pH는 다른 응집제 $FeCl_3$와 $Fe_2(SO_4)_3$의 pH와 비슷한 값을 보였다.

Keywords

References

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