Sequential Extraction을 이용한 Fly ash의 Cd 흡착 양상 평가

  • 이광헌 (서울대학교 지구환경시스템공학부) ;
  • 이승학 (서울대학교 지구환경시스템공학부) ;
  • 이아라 (서울대학교 지구환경시스템공학부) ;
  • 명동일 (서울대학교 지구환경시스템공학부) ;
  • 박준범 (서울대학교 지구환경시스템공학부) ;
  • 김형석 (중앙대학교 전기전자공학부)
  • Published : 2004.04.01

Abstract

pH has been regarded as a master variable governing the heavy metal sorption on fly ash. However, the chemical constituents in the fly ash could also suggest a potential sorption site for heavy metals. So, in this study sequential extraction method is employed to evaluate the sorption behavior of fly ash for cadmium. Two different fly ashes (S-fly ash, T-fly ash) were obtained from different power plants in Korea. First, cadmium is adsorbed under four different initial pHs. And, Cd sorbed in fly ash was sequentially desorbed following the sequential extraction method suggested by Tessier. In test results, the effect of pH increase was differently exerted in two fly ash. In S-fly ash, exchangeable fraction was dominated in low initial pH, however, as increasing initial pH, the fraction bound to carbonate increased. In the T-fly ash, regardless of initial pH the fraction bound to carbonate was major part of sorption estimated. The fraction bound to Fe/Mn oxide was about 10% in T-fly ash, and 5% in S-fly ash at high pH.