Study on the oxidative regeneration performance of Cu(Ⅱ) enhancing iron-based ionic liquid desulfurization rich solution

Objective The aim is to solve the problem of low regeneration efficiency in the wet oxidation removal of hydrogen sulfide(H₂S) using iron-based ionic liquid Fe(Ⅲ)-IL, Cu(Ⅱ) was utilized to enhance the regeneration performance of iron-based ionic liquid desulfurization rich solution.

Method In order to avoid the interference of unreacted dissolved H₂S molecules in the desulfurization rich solution on the regeneration process, a simulated iron-based ionic liquid desulfurization rich solution Fe(Ⅱ/Ⅲ)-IL was prepared, and the reliability of the simulated system was verified by characterization such as FT-IR, Raman and CV. Subsequently, Cu(Ⅱ)-IL was introduced into desulfurization rich solution, and poly(ethylene glycol) dimethyl ether (NHD) was added to reduce the viscosity of the desulfurization rich solution. And the composite system of Cu(Ⅱ)-IL+Fe(Ⅱ/Ⅲ)-IL/NHD was constructed.

Result When the mass concentration of Cu(Ⅱ) in the composite system was 4.36 g/L, the desulfurization rich solution could be completely regenerated within 120 min.

Conclusion By investigating the effects of solvent ratio, Fe(Ⅱ) and Cu(Ⅱ) mass concentrations, water mass fraction, and temperature on the regeneration performance of the desulfurization rich solution, the metal-based ionic liquid desulfurization system has been optimized, which can provide a new choice for adapting to the sustainable development needs of fossil energy exploitation and industrial application processes, such as petroleum and natural gas.