Effect of pH on the sorption and desorption of chlorinated phenols using HDTMA-montmorillonite

HDTMA-몬모릴로나이트를 이용한 염화페놀류 화합물의 흡착 및 탈착시 pH의 영향

  • 김지훈 (경북대학교 환경공학과) ;
  • 김영규 (경북대학교 화학공학과) ;
  • 신원식 (포항산업과학연구원 수질환경연구팀) ;
  • 김영훈 (경북대학교 환경공학과) ;
  • 최상준 (경북대학교 환경공학과) ;
  • 전영웅 (경북대학교 환경공학과) ;
  • 송동익 (경북대학교 화학공학과)
  • Published : 2001.09.01

Abstract

The effects of pH on the sequential sorption/desorption of chlorinated phenols (2-chlorophenol, 2.4-dichlorophenol and 2,4,5-trichlorophenol) in HDTMA-montmorillonite were investigated by maintaining pH 4.85 or 9.15 in the sequential batch sorption and desorption experiments. The chlorinated phenols are hydrophobic ionizable orginic compounds; they can exist as either neutral (pH << pKa) or anionic (pH >> pKa) forms. Among the tested chlorinated phenols, 2,4,5-trichlorophenol showed the highest sorption affinity at pH 4.85 as expected by the $K_{ow}$ . Neutral speciation at pH 4.85 exhibited higher sorption affinity than anionic speciation at pH 9.15. Our results indicates that desorption of chlorinated phenols is strongly dependent on pH of the aqueous phase. Freundlich model was used to analyze the single-solute sorption/desorption results. The ideal adsorbed solution theory(IAST) was employed to predict the hi-solute sorption/desorption equilibria.

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