Experimental validation of an optimal operating window in the Bunsen reaction section of the iodine–sulfur cycle. (7th December 2015)

• Record Type: Journal Article
• Authors: Yoon, Ho Joon; No, Hee Cheon; Lee, JeongIk; Choi, Jin Young; Pyon, Chong Un
• Is Part Of: International journal of hydrogen energy. Volume 40:Number 45(2015)
• Page Start: 15792
• Page End: 15800
• Publication Date: 2015-12-07
• Subjects: Hydrogen production -- Iodine–sulfur thermochemical cycle -- Over-azeotropic Bunsen process -- Side reaction -- Sulfur dioxide; Hydrogen as fuel -- Periodicals; Hydrogène (Combustible) -- Périodiques; Hydrogen as fuel; Periodicals; 665.81
• DOI: 10.1016/j.ijhydene.2015.05.104
• Languages: English
• ISSNs: 0360-3199

Abstract

Abstract: The Bunsen reaction section of I–S cycle has two parts, reaction and phase separation. Some previous work focused on phase separation using a simulated reaction mixture with four components (H2 SO4, HI, H2 O and I2 ). Based on phase separation data an operating window was suggested. This previous work had the limitation that reaction was not included. The present work includes both reaction and separation. We demonstrated that the Bunsen reaction ratio is higher than 2, and the azeotropic ratio(mol of HI/mol of HI + H2 O) is higher than 0.4 at 293 K and 2 mol of I2 in the feed. Bunsen reaction was promoted at a lower temperature and higher I2 content, while phase separation became worse since the generated H2 SO4 and HI remained in the HIx phase without separation. We validated the previously suggested optimal window and examined phase separation at the lower temperature region. Highlights: We investigated the Bunsen reaction via a ternary mixture of SO2 / H2 O / I2 . Bunsen reaction is dominant at a lower temperature and higher I2 content. Phase separation is dominant at a higher temperature and higher I2 content. The Bunsen reaction ratio is higher than 2 at 293K and 2 mol of I2 in the feed.