The solubility of H2S in liquid sulfur

The need for fundamental data describing the dissolution of hydrogen sulfide, H₂S, in Claus recovered liquid sulfur prompted an examination of equilibrium H₂S solubility at typical industrial condensation temperatures and partial pressures. An FT/IR absorption technique has been described and new H₂S solubility measurements have been reported for partial H₂S pressures from 0.4 to 56 kPa and temperatures from 120 to 155 °C. The measurements were combined with previously reported values for atmospheric pressures of H₂S and used to calibrate a semi-empirical equation for the Henry's law solubility in liquid sulfur as a function of temperature. Estimations were compared to Claus plant field data and appear to underestimate the H₂S solubility for the first and second catalyst condenser stages. This underestimation was attributed to rapid condensation resulting in super-saturation of the recovered sulfur liquid, or an inaccurate measurement of the condensation temperatures.