The activity of calcium in calcium-metal-fluoride fluxes
- Univ. of Tokyo (Japan). Dept. of Metallurgy
The standard Gibbs energy of reaction Ca (1) + {und O} (mass pct, in Zr) = CaO (s) has been determined as follows by equilibrating molten calcium with solid zirconium in a CaO crucible: {Delta}G{degree} = {minus}64,300({+-}700) + 19.8({+-}3.5)T J/mol (1,373 to 1,623 K). The activities of calcium in the CaO{sub satd.}-Ca-MF{sub 2} (M: Ca, Ba, Mg) and CaO{sub satd.}-Ca-NaF systems were measured as a function of calcium composition at high calcium contents at 1,473 K on the basis of the standard Gibbs energy. The activities of calcium increase in the order of CaF{sub 2}, BaF{sub 2}, and MgF{sub 2} at the same calcium fraction of these fluxes. The observed activities are compared with those estimated by using the Temkin model for ionic solutions. Furthermore, the possibility of the removal of tramp elements such as tin, arsenic, antimony, bismuth, and lead from carbon-saturated iron by using calcium-metal-fluoride fluxes is discussed.
- Sponsoring Organization:
- USDOE
- OSTI ID:
- 94386
- Journal Information:
- Metallurgical Transactions, B, Journal Name: Metallurgical Transactions, B Journal Issue: 4 Vol. 26; ISSN MTTBCR; ISSN 0360-2141
- Country of Publication:
- United States
- Language:
- English
Similar Records
The thermodynamics of the Ni-Co-S ternary system
Calcium deoxidation equilibrium in liquid iron