Thermodynamics of Spherical Sponge Iron Reduced by Hydrogen

Abstract:

Spherical sponge iron (SSI) with high activity and intension could be prepared through direct reduction by hydrogen. To optimize the reduction technology, thermodynamics of SSI reduction was investigated. Oxygen residue ratio in SSI declined with the reaction time despite of reaction temperature. It was concluded that SSI reduced by hydrogen appeared to be the first-order reaction, and the apparent reaction rate constant k was 0.289 h-1 to 3.819 h-1. Activity energy of SSI reduction was 22.19 kJ•mol-1 and 81.58 kJ•mol-1 corresponding to the lower temperature and higher temperature. When the temperature was lower than T4, the reaction rate was lower. Consequently, the optimized temperature should be controlled more than T5 to elevate the reduction rate.

• Periodical: Advanced Materials Research (Volume 487)
• Pages: 677-681
• DOI: https://doi.org/10.4028/www.scientific.net/AMR.487.677
• Online since: March 2012
• Authors: Jun Guo Li, Shou Zhang Li, Wei Tian
• Keywords: Activation Energy, Reaction Rate Constant, Spherical Sponge Iron (SSI), Thermodynamic

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