Skip to main content
placeholder image

Activity-composition relations of MnO in MnO-CrOx-CaO-SiO2-containing melts

Journal Article


Abstract


  • The MnO activities in (MnO-CrOi-CaO-SiO2)-containing melts, which were saturated with the (Mn, Cr)3O4 spinel phase, were determined at 1500 °C under an oxygen partial pressure of 10-89.9 atm. This was done by equilibrating the samples with platinum. The activity of MnO in the melt was then calculated from the activity coefficient of manganese in the resultant Pt-Cr-Mn alloy. Darken's quadratic formalism for ternary metallic solutions was used to calculate the activity coefficient of manganese in the Pt-Cr-Mn system, in which platinum was considered to be the solvent. It was found that an increase in the concentration of MnO in the melt increases both the MnO activity and the activity coefficient of MnO. For a constant MnO concentration in the (MnO-CrOx-CaO-SiO2)containing melts, the activity of MnO can be increased by increasing the basicity of the melt. In order to obtain high-manganese recoveries from (MnO-CrOx-CaO-SiO2)-containing melts into an alloy phase, basic slags in which the activity coefficient of MnO is high should therefore be used.

Publication Date


  • 1997

Citation


  • Garbers-Craig, A. M., & Dippenaar, R. J. (1997). Activity-composition relations of MnO in MnO-CrOx-CaO-SiO2-containing melts. Metallurgical and Materials Transactions B: Process Metallurgy and Materials Processing Science, 28(4), 619-624. doi:10.1007/s11663-997-0034-2

Scopus Eid


  • 2-s2.0-0031212979

Web Of Science Accession Number


Start Page


  • 619

End Page


  • 624

Volume


  • 28

Issue


  • 4

Abstract


  • The MnO activities in (MnO-CrOi-CaO-SiO2)-containing melts, which were saturated with the (Mn, Cr)3O4 spinel phase, were determined at 1500 °C under an oxygen partial pressure of 10-89.9 atm. This was done by equilibrating the samples with platinum. The activity of MnO in the melt was then calculated from the activity coefficient of manganese in the resultant Pt-Cr-Mn alloy. Darken's quadratic formalism for ternary metallic solutions was used to calculate the activity coefficient of manganese in the Pt-Cr-Mn system, in which platinum was considered to be the solvent. It was found that an increase in the concentration of MnO in the melt increases both the MnO activity and the activity coefficient of MnO. For a constant MnO concentration in the (MnO-CrOx-CaO-SiO2)containing melts, the activity of MnO can be increased by increasing the basicity of the melt. In order to obtain high-manganese recoveries from (MnO-CrOx-CaO-SiO2)-containing melts into an alloy phase, basic slags in which the activity coefficient of MnO is high should therefore be used.

Publication Date


  • 1997

Citation


  • Garbers-Craig, A. M., & Dippenaar, R. J. (1997). Activity-composition relations of MnO in MnO-CrOx-CaO-SiO2-containing melts. Metallurgical and Materials Transactions B: Process Metallurgy and Materials Processing Science, 28(4), 619-624. doi:10.1007/s11663-997-0034-2

Scopus Eid


  • 2-s2.0-0031212979

Web Of Science Accession Number


Start Page


  • 619

End Page


  • 624

Volume


  • 28

Issue


  • 4