Representation of Oxidation Ability for Metallurgical Slags Based on the Ion and Molecule Coexistence Theory

Abstract

The defined oxidation ability of metallurgical slags based on the ion and molecule coexistence theory (IMCT), i.e., the comprehensive mass action concentration N FetO of iron oxides, has been verified through comparing the calculated N FetO and the reported activity a FetO of iron oxides in the selected Fe t O-containing slag systems. To calculate the defined comprehensive mass action concentration N FetO of iron oxides in the selected slag systems, a thermodynamic model for calculating the mass action concentrations of structural units or ion couples in CaO-SiO 2 -MgO-FeO-Fe 2 O 3 -MnO-Al 2 O 3 -P 2 O 5 type slags, i.e., the IMCT-N i thermodynamic model, has been developed. The defined comprehensive mass action concentration N FetO of iron oxides is more accurate than the measured activity a FetO of iron oxides to represent the slag oxidation ability of the selected Fe t O-containing slag systems. The calculated comprehensive mass action concentration N FetO of iron oxides or the reported activity a FetO of iron oxides in the selected Fe t O-containing slag systems shows an increase tendency with an increase of optical basicity of the slags by taking L FeO as 0.93 and L Fe 2 O 3 as 0.69, or L FeO as 1.0 and L Fe 2 O 3 as 0.75, rather than by taking L FeO as 0.51 and L Fe 2 O 3 as 0.48. The slag oxidation ability represented by the defined comprehensive mass action concentration N FetO of iron oxides or the measured activity a FetO of iron oxides is not only decided by the effects of iron oxides, but also by the comprehensive effects of both iron oxides and basic oxides as CaO or MgO or MnO in the selected Fe t O-containing slag systems.[ Ã ] X.

Retraction: A Prediction Model of Phosphorus Distribution between CaO–SiO2–MgO–FeO–Fe2O3–P2O5 Slags and Liquid Iron

“…[14][15][16][17][18][19][20]23) equilibrium mole numbers ni of all abovementioned structural units in 100 g slags equilibrated with liquid iron at metallurgical temperatures have been also given out in Table 1. According to the ion and molecule coexistence theory, [14][15][16][17][18][19][20]23) each ion couple is electroneutral and can be electrolyzed into cation and anion based on electrovalence balance principle. Hence, ion couple (Me 2+ +O 2-) with a fixed amount under equilibrium condition can produce two times amount of structural units, i.e.,…”

“…The total equilibrium mole number Σn i of all structural units in 100 g slags equilibrated with liquid iron can be expressed as follows ...... (1) With respect to the definition of mass action concentrations [14][15][16][17][18][19][20]23) N i for structural units, which is a ratio of equilibrium mole number of structural units i to the total equilibrium mole numbers of all structural units in a close system with a fixed amount, N i of structural units i and ion couples (Me 2+ +O All definitions of Ni for formed ion couples from simple ions, simple and complex molecules in CaO-SiO 2 -MgOFeO-Fe2O3-P2O5 slags were listed in Table 1. Meanwhile, it should be pointed out that the physicochemistry meaning of N i is almost consistent with the traditionally applied activity ai of component i in slags, in which pure matter is chosen as standard state and mole fraction is selected as concentration unit.…”

“…Meanwhile, it should be pointed out that the physicochemistry meaning of N i is almost consistent with the traditionally applied activity ai of component i in slags, in which pure matter is chosen as standard state and mole fraction is selected as concentration unit. [14][15][16][17][18][19][20]23) The chemical reaction formulas of 20 kinds of possibly formed complex molecules, their standard molar Gibbs free energy of formation reactions as a function of absolute temperature T, reaction equilibrium constant and presentation of mass action concentration of all complex molecules N ci expressed by using ,…”

“…The mass conservation equations of six components in 100 g of CaO-SiO2-MgO-FeO-Fe2O3-P2O5 slags equilibrated with liquid iron can be established according to the definition [14][15][16][17][18][19][20]23) of n i and mass action concentrations N i of all structural units listed in Table 1 …”

“…Meanwhile, it should be pointed out that the defined comprehensive mass action concentration of iron oxides in slags can be applied to accurately replace activity of relative pure liquid matter as standard state in previous publication. 23) The IMCT [14][15][16][17][18][19][20]23) proposed that all iron oxides in metallurgical slags are composed of ion couple ( The related values of interaction coefficients are chosen as =-0.2, =-0.07. Figs.…”