An investigation of the gas-solid interface reaction

Abstract The isotopic exchange between H2S and D2 on molybdenum disulfide and manganese sulfide has been studied kinetically between 420° and 500 °C. The reaction proceeded via these steps: & H_2S+D_2=D_2S+H_2 & H_2+D_2=2HD From the analysis of the kinetic data, the rate constant of the sulfurization of both metal sulfides by "hydrogen sulfide," ki, and that of their reduction by "hydrogen," ki′, were calculated. The dependence of these rate constants on the sulfur activity was determined. A possible mechanism of the reaction at the surface of the sulfides is discussed in this paper.