Minerals & Metallurgical Processing

, Volume 34, Issue 1, pp 44–52 | Cite as

Kinetic study of titanium-bearing electric arc furnace molten slag treated by molten sodium hydroxide

  • Y. Li
  • H. Ni
  • Y. Zhou
  • D. Li
  • F. Zheng
  • M. Zhang
  • M. GuoEmail author


In the present work, we investigate the effects of roasting temperature and time on the transformation of the titanium (Ti)-bearing phase and magnesium aluminate spinel (MgAl2O4) phase in Ti-bearing electric arc furnace molten slag during the molten sodium hydroxide (NaOH) treatment process. With applied temperature of 700 °C for 60 min, and a mass ratio of Ti-bearing electric arc furnace slag to NaOH, or Rslag/NaOH, of 1:1.2, the conversion ratios of the Ti-bearing phase and the MgAl2O4 phase reached about 98.3 percent and 88.1 percent, respectively. Moreover, investigation of the reaction kinetics indicate that the conversion of these phases during the molten NaOH treatment process is a typical solid-liquid reaction, and it can be theoretically described by the unreacted shrinking core model. The conversion ratio of the Ti-bearing phase was found to be controlled by the chemical reaction step, with an apparent activation energy of 41.76 kJ/mol. The decomposition of the MgAl2O4 phase was found to be controlled by the surface chemical reaction in the early stage of 0 to 20 min from start of reaction, changing to diffusion control in the later stage of 20 to 60 min. The apparent activation energies of the process were determined as 55.88 and 22.72 kJ/mol, respectively.

Key words

Titanium-bearing electric arc furnace molten slag Kinetics Sodium hydroxide 


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Copyright information

© The Society for Mining, Metallurgy & Exploration 2017

Authors and Affiliations

  • Y. Li
    • 1
    • 2
  • H. Ni
    • 1
  • Y. Zhou
    • 1
  • D. Li
    • 1
  • F. Zheng
    • 3
  • M. Zhang
    • 2
  • M. Guo
    • 2
    Email author
  1. 1.The State Key Laboratory for Refractories and Metallurgy, School of Materials and MetallurgyWuhan University of Science and TechnologyWuhanChina
  2. 2.School of Metallurgical and Ecological EngineeringUniversity of Science and Technology BeijingBeijingChina
  3. 3.Nano-science and Nano-technology Research Center, Materials Science and Engineering CollegeShanghai UniversityShanghaiChina

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