The Control of Side Reactions in Bunsen Reaction Section of Sulfur-Iodine Hydrogen Production Process

황-요오드 수소 생산 공정의 분젠 반응 부분에서 부반응 제어

  • Lee, Kwang-Jin (Department of Fine Chemical Engineering and Chemistry, BK21-E2M, Chungnam National Univ.) ;
  • Hong, Dong-Woo (Department of Fine Chemical Engineering and Chemistry, BK21-E2M, Chungnam National Univ.) ;
  • Kim, Young-Ho (Department of Fine Chemical Engineering and Chemistry, BK21-E2M, Chungnam National Univ.) ;
  • Park, Chu-Sik (Korea Institute of Energy Research) ;
  • Bae, Ki-Kwang (Korea Institute of Energy Research)
  • 이광진 (충남대학교 공과대학 정밀공업화학과, BK21-에너지환경소재사업단) ;
  • 홍동우 (충남대학교 공과대학 정밀공업화학과, BK21-에너지환경소재사업단) ;
  • 김영호 (충남대학교 공과대학 정밀공업화학과, BK21-에너지환경소재사업단) ;
  • 박주식 (한국에너지기술연구원) ;
  • 배기광 (한국에너지기술연구원)
  • Published : 2008.12.30

Abstract

For continuous operation of the sulfur-iodine(SI) thermochemical cycle, which is expected practical method for massive hydrogen production, suggesting operation conditions at steady state is very important. Especially, in the Bunsen reaction section, the Bunsen reaction as well as side reactions is occurring simultaneously. Therefore, we studied on the relation between the variation of compositions in product solution and side reactions. The experiments for Bunsen reaction were carried out in the temperature range, from 268 to 353 K, and in the $I_2/H_2O$ molar ratio of $0.094{\sim}0.297$ under a continuous flow of $SO_2$ gas. As the result, sulfur formed predominantly with increasing temperature and decreasing $I_2/H_2O$ molar ratios. The molar ratios of $H_2O/H_2SO_4$ and $HI/H_2SO_4$ in global system were decreased as the more side reaction occurred. A side reactions did not appear at $I_2/H_2O$ molar ratios, saturated with $I_2$, irrespective of the temperature change. We concluded that it caused by the increasing stability of an $I_{2x}H^+$ complex and a steric hindrance with increasing $I_2/HI$ molar ratios.

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