Journal of the Korean Crystal Growth and Crystal Technology (한국결정성장학회지)

The Korea Association of Crystal Growth (한국결정성장학회)
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Crystal growth studies of $SF_6$ clathrate hydrate

$SF_6$ 하이드레이트 결정의 성장 특성에 대한 연구

  • Lee, Yoon-Seok (School of Materials Science and Engineering, Pusan National University) ;
  • Lee, Ju-Dong (Dongnam Technology Service Division, Korea Institute of Industrial Technology) ;
  • Lee, Bo-Ram (Department of Chemical Engineering, Pohang University of Science and Technology) ;
  • Lee, Hyun-Ju (School of Materials Science and Engineering, Pusan National University) ;
  • Lee, Eun-Kyung (School of Materials Science and Engineering, Pusan National University) ;
  • Kim, Soo-Min (School of Materials Science and Engineering, Pusan National University) ;
  • Kim, Young-Seok (Dongnam Technology Service Division, Korea Institute of Industrial Technology) ;
  • Yoon, Seog-Young (School of Materials Science and Engineering, Pusan National University) ;
  • Kim, Yang-Do (School of Materials Science and Engineering, Pusan National University)
  • 이윤석 (부산대학교 재료공학부) ;
  • 이주동 (한국생산기술 연구원 동남권기술지원본부) ;
  • 이보람 (포항공과대학교 화학공학과) ;
  • 이현주 (부산대학교 재료공학부) ;
  • 이은경 (부산대학교 재료공학부) ;
  • 김수민 (부산대학교 재료공학부) ;
  • 김영석 (한국생산기술 연구원 동남권기술지원본부) ;
  • 윤석영 (부산대학교 재료공학부) ;
  • 김양도 (부산대학교 재료공학부)
  • Published : 2009.10.31
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Abstract

In this study, we investigated morphological characteristics of $SF_6$ clathrate hydrate crystals to understand its formation and growth mechanism. $SF_6$ clathrate hydrate crystals were formed in high-pressure reaction cell charged with pure water and $SF_6$ gas at constant pressure and temperature. Two-phase ($SF_6$ gas/aqueous solution) and three-phase ($SF_6$ gas/aqueous solution/$SF_6$ liquid) conditions were investigated, In both conditions, dendritic shape hydrate crystals were grown as like fibriform crystals along upward growth direction at the gas/aqueous solution interface. In the case of the reaction process of three-phase condition, when the $SF_6$ gas bubbles which were generated in $SF_6$ liquid phase due to the reduction of reaction cell pressure stuck to the gas/aqueous interfaces, the hydrate phase were appeared at the surface of the bubbles. This paper presents the detail growth characteristics of $SF_6$ hydrate crystals including crystal nucleation, migration, growth and interference.

본 연구에서는 $SF_6$ 가스 포접 하이드레이트 결정이 생성되고 성장하는 메커니즘의 특성을 기술하였다. 실험은 일정한 압력과 온도에서 2상 실험($SF_6$ 기상/수용액상)과 3상 실험($SF_6$ 기상/수용액상/$SF_6$ 액상)의 서로 다른 두 가지 상 조건에서 이루어졌다. 두 조건 모두 기체 영역과 수용액 영역 사이의 경계면에서 하이드레이트 결정의 수지상이 섬유상 형태로 상향 성장하는 거동을 보였다. 3상 실험의 경우 하이드레이트 생성이 진행됨에 따라, 반응기 내부압의 감소로$SF_6$ 액상에서 생성된 기포가 기체와 수용액 계면의 막에 도달하여 기포의 표면이 하이드레이트로 전환되었다. 본 논문에서는 결정의 핵생성과 이동, 성장, 간섭을 중심으로 $SF_6$ 가스하이드레이트 결정의 성장 특성을 기술하였다.

Keywords

References

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