The diffusion coefficient of H2S in liquid sulfur

The diffusion coefficient of H2S in liquid sulfur is a key kinetic parameter that has been missing in literature. In this paper, a pressure decay method was applied to measure the diffusion coefficients of H2S in liquid sulfur at 403 and 423 K. This pressure decay process was then modeled by taking the simultaneous diffusion and reversible chemical reactions between H2S and liquid sulfur into consideration. The diffusion coefficients and reaction rate constants were numerically determined by fitting theoretical curves to experimental data using Finite Element Method and Genetic Algorithm. The solubility of H2S in liquid sulfur at 403 and 423 K was also calculated and the results agreed with the semi-empirical correlation lately reported in literature. This study further extended the validity of the correlation to higher partial H2S pressure conditions.

► An H2S-S(l) diffusion-reaction system was studied at 403 and 423 K.
► Pressure decay method to measure diffusivity and reaction rate constant.
► Simultaneous diffusion and reaction was modeled and numerically solved.
► Solubility data supports the lately published correlation.