THE EFFECT OF HYDROGEN ON THE DEFECT STRUCTURE OF MANGANOUS SULFIDE AND ON THE SULFIDATION RATE OF MANGANESE

The effect of the presence of various possible hydrogen species in MnS on the concentration of its native defects and on the parabolic rate constant for the sulfidation of Mn at high temperatures is examined. This allows to resolve the discrepancy between the experimental values of the rate constant for the sulfidation of manganese in H-2-H2S mixtures and those calculated on the basis of the defect structure of pure MnS. It is concluded that the most likely form of hydrogen doping is due to the simultaneous presence of two species, i.e. the proton interstitials and the hydride ions in substitutional sulfur sites.