Determination of standard free energies of formation of Ca3P2 and Ca2Sn at high temperatures
Abstract
The standard free energies of formation of calcium phosphide and calcium stannide were determined by a chemical equilibration technique, yielding the following results: 3Ca(1) + P2(g) = Ca3P2(s) Δ G° = -653,460(±7110) + 144.01(±4.98) T (J/mol)1000 °C to 1300 °C2Ca(1) + Sn(1) = Ca2Sn(s) Δ G° = -353,970(±1670) + 79.28(±1.26) T (J/mol)1000 °C to 1300 °C 1120 °C The experimental data to express the thermodynamics for removal of phosphorus and tin from molten iron by calcium based slags by other investigators were discussed in terms of the activity co-efficients of Ca3P2 and Ca2Sn in slag melts by using the present results described above.
- Publication:
-
Metallurgical Transactions B
- Pub Date:
- June 1988
- DOI:
- 10.1007/BF02657741
- Bibcode:
- 1988MTB....19..433M