Activities of FeO in CaO-Al2O3-SiO2-FeO and CaO-Al2O3-CaF2-FeO Slags.

Abstract

Activity coefficients of FeO in molten CaO-Al203-Si02-FeO (50/0) slags were determined at 1 673 and 1873K by equilibrating the slags with copper-iron alloys in a controlled oxygen partial pressure (P02=5.71 xl0~12atm at 1 673 K, 1.90xlO10atm at 1 873 K). Activity coefficients of iron in copperiron (alloys at 1 673 Kwere preliminarily determined by controlling the activity of iron using FeO-Cr203 saturated with Cr203 in a various oxygen partial pressures (P02=3.66x I 0~12-g.1 4x I 0~1~a tm), It was found that the activity coefficients of FeOobey Henry's law, and have the maximum value when the ratio of NcaolNsi02 is about 2 at a constant Al203 content. Theactivity coefficients of iron in copper-iron alloy referred to pure liquid were determined as In yF*=2.76-1 1 ,3NFe ' The effect of a CaF2addition to the CaO-Al203-FeOsystem on the activity coefficient of FeO was also investigated at 1 723 K.

Activities of FeO in CaO-SiO2-Al2O3-MgO-FeO slags

“…In Fig.4, the a FeO values show positive deviation from ideality at a low FeO concentration. This result indicates that the cativity of iron oxide obeys Henry's law and agrees with Taniguchi, et al [14] 0.20 The relationship between the FeO activities and basicity is gived in Fig.6. For slags with constant content of MgO, Al 2 O 3 and FeO, Fig.6 shows that a continuous increase in the FeO activities with increase of (%CaO)/(%SiO 2 ) from 1.03 to 1.3.…”

Activities of FexO in Industrial Slags Used for External Removal of Phosphorous from Hot Metal

“…The activity of FexO in the slag decreases according to the isoactivity curves. The same tendency can be observed with the results after Hawkins and Davis [19] and Iwase et al [20] for a CaOCaF 2 FexO ternary system and Taniguchi et al [21] for a CaOCaF 2 Al 2 O 3 FexO quaternary system.…”

Retraction: Representation of Dephosphorization Ability for CaO–Containing Slags Based on the Ion and Molecule Coexistence Theory

“…In this study, the mass action concentration of iron oxides Fe t O, i.e., N Fe t O , is recommended to present slag oxidization ability. The IMCT [21][22][23][24][25][26][27][28] proposed that all iron oxides in metallurgical slags are composed of ion couple (Fe In order to examine the reliability of the IMCT-Ni model developed in the present study based on the ion and molecule coexistence theory, the calculated mass action concentrations of iron oxides N Fe t O in CaO-FeO-Fe 2 O 3 slags, 32,59,60) CaO-SiO 2 -FeO-Fe 2 O 3 slags, 33,38,[61][62][63][64][65][66] CaO-SiO 2 -FeOFe2O3-Al2O3 slags, 34) CaO-SiO2-FeO-Fe2O3-MgO slags, 35,67) CaO-SiO2-MgO-FeO-Fe2O3-MnO slags, 36) CaO-SiO2-MgO-FeO-P2O5 slags, 37) MgO-FeO-Fe2O3-P2O5 slags, 38) CaO-FeO-Fe2O3-P2O5 slags 39) and CaO-SiO2-MgO-FeO-Fe 2 O 3 -MnO-Al 2 O 3 -P 2 O 5 slags 40) were compared with all available measured Fe t O activities a Fe t O, measured at different temperatures reported in various literatures by different investigators, respectively. The experimental techniques employed by these investigators for FetO activity measurements in different slags were summarized in Table 2.…”