Kinetic Studies on the Dissolution of Nitrogen into Molten Iron by ¹⁴N-¹⁵N Isotope Exchange Reaction

Abstract

The dissolution of nitrogen into molten iron in the temperature range from 1823 to 1923 K has been investigated using an isotope exchange reaction. The feature of this technique is that the chemical reaction rate can be determined without the effect of mass transport in liquid iron. It was experimentally shown that the dissolution of nitrogen is a first order reaction with respect to the partial pressure of nitrogen. The rate constant (k) for an extremely purified molten iron is expressed as follows with an activation energy of 95.0 kJ/mol.
log k (mol/cm²·s·atm)=–4960(±1350)/T–1.83(±0.03)
Even a very small amount of oxygen contained in the gas has been observed to retard the reaction considerably.