Thermodynamics and Kinetics of Burning Iron
SourceMacroscopic kinetic analysis of the burning of 0.1 and 0.2-cm-diameter iron rods in pure oxygen at pressures between 0.3 MPa and 10 MPa, and 0.32-cm- diameter iron rods in pure oxygen at pressures between 0.3 MPa and 5 MPa indicates that the kinetic reaction occurs at the phase boundary between the molten oxide product and the liquid iron core. An apparent activation energy of 246.8 kJ/mol Fe(l) is consistent with this analysis. The surface area of the liquid oxide/liquid iron phase-boundary is appropriate for describing the reaction. An enthalpy of reaction of -365.2 kJ/mol Fe(l) at 298K is consistent for the burning of iron. The Langmuir-Hinshelwood- Hougen-Watson mechanism is consistent with the flammability data for iron. In the linear range of that mechanism an appropriate rate equation is: RFe = 7.05E3exp(-2.9684E4/T)Po21/2gm cm-2s-1