Simultaneous Absorption of Oxygen and Hydrogen in Liquid Iron from Water Vapour

Abstract

On the assumption that water vapour should dissociate into gaseous oxy gen and hydrogen at gas-metali nterface and also their partial pressures are in equilibrium, the rates of absorption of oxygen in liquid iron rom water vapour between 0·1 and 0·0032atmpH²o is considered to be controlled by the activation process of adsorbed oxygen atom, namely chemical reaction, and be proportional to(pH₂oi/PHi)².
The hydrogen absorption of liquid iron may be also predicted by combining the dissolution p rocess of dissociated hydrogen atom with the oxidization process of hydrogen in liquid iron by adsorbed oxygen atom.
It is generally estimated that the concentration of hydrogen in liquid iron increases at early period of reaction, and then decreases with increasing oxygen concentration in liquid iron as already shown in the carbon absorption from carbon dioxide, because of the simultaneous absorption of oxygen from water vapour. At higher partial pressure of water vapour, for example, 0·1atmpH2O, liquid iron will contain less hydrogen than at lower partial pressure.
If the rate of absorption of oxygen is constant independent of partial pressure of water vapour, the concen-tration of hydrogen increases with increasing partial pressure of water vapour in gas phase. On the other hand, if the concentration of oxygen in liquid iron decreases, the hydrogen dissolution occurs more markedly.