대한환경공학회지 (Journal of Korean Society of Environmental Engineers)

  • 제27권3호
  • /
  • Pages.273-279
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  • 2005
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  • 1225-5025(pISSN)
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  • 2383-7810(eISSN)
대한환경공학회 (Korean Society of Environmental Engineers)
권호 표지

초임계수 중에서 NaOH 첨가에 의한 o-chlorophenol의 분해 및 부산물 생성에 관한 연구

Study on the Formation of Byproducts and the Decomposition of o-Chlorophenol by Addition of NaOH in Supercritical Water

  • 송병주 (전북대학교 환경공학과) ;
  • 김종국 (전북대학교 환경공학과) ;
  • 이근희 (부산광역시청 환경정책과)
  • Song, Byung-Joo (Environmental Engineering, Chonbuk National University) ;
  • Kim, Jong-Guk (Environmental Engineering, Chonbuk National University) ;
  • Lee, Geun-Hee (Environmental Policy Division, Busan Metropolitan City Hall)
  • 발행 : 2005.03.31
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초록

본 연구에서는 초임계수 중에서 o-chlorophenol(o-CP)의 분해 및 중간 생성물 형성에 미치는 NaOH의 효과를 검토하였다. NaOH를 첨가하지 않은 경우 o-CP의 분해율은 20% 이하로 낮았으나 NaOH를 o-CP의 몰 농도에 대하여 200% 이상 첨가한 경우 체류 시간 1초 이내에 100% 가까운 분해율을 얻을 수 있었다. 분해 과정에서 생성되는 PAHs 및 페놀 화합물의 양도 크게 감소하는 경향을 나타내어 NaOH 첨가가 부산물 생성 억제에도 효과가 있는 것으로 나타났다. NaOH를 첨가하지 않은 경우와 첨가한 경우 공통적으로 페놀, 크레졸, 염화 페놀류, PAHs 및 1-indanone, dibenzofuran, dibenzo-dioxin, p,p'-dihydroxybiphenyl 등과 같이 2개 이상의 벤젠 고리가 산소로 연결된 화합물이 검출되었다. 반면에 NaOH를 첨가한 경우에는 2-ethylphenol, o-hydroxyacetophenone, hydroquinone, 4-allylphenol, 3-phenoxyphenol 및 4,4'-oxybisphenol이 생성되어 NaOH 첨가로 인한 o-CP의 분해는 훨씬 더 복잡한 과정을 통해서 이루어지는 것으로 판단되었다. 또한 페놀의 소각 과정에서 생성되는 것으로 보고된 화합물인 dibenzofuran, dibenzo-p-dioxin 등도 본 연구에서도 생성된 것으로부터 소각과 초임계수에 의한 열분해 사이에는 상관성이 있는 것으로 판단되었다.

The degradation of o-chlorophenol(o-CP) in the presence of NaOH and the byproducts formed were investigated in a supercritical water(SCW) destruction process. The conversion of o-CP in the absence of NaOH was less than 20%, however it showed 100% conversion in the presence of NaOH(mole ratio[NaOH]/[o-CP] over than 2) with a residence time of less than 1 second. The formation of PAHs and the phenolic compounds formed were decreased in the presence of NaOH. The results revealed that the formation of byproducts during the destruction of o-CP in SCW was effected by the addition of NaOH. Phenol, cresols, chlorinated phenols, PAHs, p,p'-dihydroxybiphenyl and oxygenated polyaromatic compounds such as 1-indanone, dibenzofuran and dibenzo-p-dioxin were detected in both conditions(presence and absence of NaOH). At the same time, in the presence of NaOH, 2-ethylphenol, o-hydroxyacetophenone, hydroquinone, 4-allylphenol, 3-phenoxyphenol and 4,4'-oxybisphenol were also detected. The observed results suggest that the destruction of o-CP in SCW with NaOH occurs through a number of complicated reaction pathways. Dibenzofuran and dibenzo-p-dioxin were also detected during destruction of o-CP by SCW. The above observation suggests that there may be a common relationship between the thermal incineration process and SCW decomposition process.

키워드

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