Solubility and Diffusion Coefficient of Hydrogen Sulphide in Polyethylene Glycol 400 from 100 to 140°C

The limitation of greenhouse and sour gas emissions in the atmosphere, such as hydrogen sulphide, is nowadays a major preoccupation in industrial processes. In this context, the Clauspol process is a Claus tail gas treatment able to respond to this challenge of reaching high sulphur recovery. It consists of chemically converting H 2 S and SO 2 into elementary sulphur in a polyethylene glycol 400 solvent. The optimisation of the process design requires a precise knowledge of both the solubility and diffusivity of these gases in this solvent. Hence, this work presents, in the case of H 2 S, experimental measurements and modelling of these data in the process operating conditions. The solubility data are modelled by the Sanchez-Lacombe equation of state with a single temperatureindependent binary interaction coefficient. The diffusion coefficients are determined by applying the Infinite-Acting model to the experimental pressure decay curve. It is found to be inversely proportional to the viscosity of the solvent.