Abstract: In order to solve the problem of removing H₂S from small to medium-scale conventional sulfur-containing natural gas, a kind of FeCl₃/UREA deep eutectic solvent (DES) was synthesized from UREA and ferric chloride hexahydrate (FeCl₃.6H₂O) with addition of CuCl₂ to obtain FeCl₃/UREA-CuCl₂ desulfurizer. The structure and thermal stability of the DES were determined, and the effects of raw material ratio, CuCl₂ concentration, H₂S gas flow rate and temperature on the desulfurization performance were investigated through desulfurization experiment, and the regeneration process was also investigated. The results showed that the DES could exist stably at 80℃, and the DES with molar ratio of FeCl₃/UREA of 1:1 had better desulfurization performance.The introduction of CuCl₂ could significantly improve the desulfurization performance, the maximum sulfur capacity was 9.64 g/L. The desulfurizer is more suitable for desulfurization at lower gas flow rate and can be regenerated by passing O₂. The effect of the desulfurizer has little change after repeated use. The product of desulfurization is high purity rhombohedral sulfur (α-sulfur). The desulfurizer has the advantages of low cost of raw materials, simple synthesis, and high efficiency of oxidationand absorption of H₂S and conversion of H₂S into high purity sulfur,which can provide a reference for industrial natural gas desulfurization.

Key words: deep eutectic solvent, desulfurization solution, hydrogen sulfide, sulfur, wet oxidation