Study on the Effect of H₂S on the Adsorption of CH₄, N₂, and CO₂ by Anthracite

In order to study the effect of H₂S on gas adsorption in a coal seam, the adsorption characteristics of single-component CO₂, CH₄, N₂, and H₂S and multicomponent H₂S mixed with CO₂, CH₄, and N₂ by anthracite were simulated by using the Grand Canonical Ensemble Monte Carlo (GCMC) method. The results show that the adsorption capacity of CO₂, CH₄, N₂, and H₂S in anthracite decreases with increasing temperature and increases with increasing pressure. The isothermal adsorption curves of CO₂, CH₄, N₂, and H₂S and different proportions of H₂S/CH₄, H₂S/N₂, and H₂S/CO₂ are highly consistent with the Langmuir equation, and the R ² is above 0.99. Under different temperature and pressure conditions, the adsorption capacity of H₂S and CO₂ is stronger than that of coal for N₂ and CH₄, and the adsorption capacity difference is about 3 mmol/g. There is competitive adsorption among H₂S, CO₂, CH₄, and N₂, and H₂S has a superior adsorption property. When H₂S and other gases exist at the same time, the adsorption capacities of CH₄, N₂, and CO₂ are reduced by 48-60%, 81-91%, and 51-66%, respectively.