Molecular simulation of the adsorption characteristics of H2S in calcite slit-like pores

Abstract

Hydrogen sulfide (H2S) in acid gas reservoirs is an important source of sulfur deposition in rock reservoirs. Studying the adsorption behavior of H2S in calcite slit-like pore is of great significance for predicting the amount of sulfur in natural gas. In this paper, the grand canonical Monte Carlo (GCMC) method is used to investigate the adsorption of H2S in calcite with slit-like pore. Moreover, the effects of different pressures, temperatures and pore sizes on the adsorption characteristics are discussed. The results showed that the adsorption of H2S goes up with the increasing of the pressure and gradually reaches a saturation level. And the adsorption of H2S decreases with the increasing of the temperature. The excess adsorption of H2S first increases and then decreases with the increasing of the pressure. The effect of the size on the excess adsorption capacity changes with the pressure. Meanwhile, the peak of the adsorbate near the surface of the adsorbent shows a nonmonotonic trend with the pressure.