| H2S existed in industrial processes would not only result in corrosion of metal pipes and equipments and catalyst poisoning, but also cause air pollution and threats to personal safety. It is important and urgent to remove H2S from industrial waste gas. Refer to desulfurization of H2S, wet oxidation desulfurization for hydrogen sulfide were widely used with many advantages, such as recycle of desulfurization agent and recovery of sulfur from the exhaust gas. However, it is necessary to add bases and fresh desulfurization agent continuously to keep pH value at ca.8 and optimize the desulfurization performance, which finally produce huge amount of unbiodegradated wastewater containing inorganic salts. Therefore, it is of great significant to explore new green wet oxidation desulfurization process.Based on the natural feature of Fe-based ionic liquids, non-aqueous wet oxidation desulfurization of hydrogen sulfide was proposed in this work. The Fe-based ionic liquid (Fe-IL) was synthesized directly by mixing 1:2 mole ratio of 1-butyl-3-methylimidazolium(BmimCl) and FeCl3·6H2O at room temperature. The Fe-IL was characterized by FT-IR/Raman, moisture determination, elemental analysis, TG, redox potential (ORP) and acid characterization. The vSo-H of H2O in FT-IR at 1630cm-1 and 3300cm-1 were not found in the Fe-IL, which is agreement with the result by moisture determination that the Fe-IL contained no water. The elemental result indicated that the chemical structure of Fe-IL could be expressed as unstoichiometric [Bmim]Fe0.9Cl4.7. The Raman peaks at 120.33cm-1 and 333cm-1 showed that FeCl4- was the only existing form of Fe in Fe-IL. From TG and ORP, the Fe-IL was only decomposed at 300℃and presented high ORP value at 694mv, which showed high thermostability and oxidation property. The IR peak at 1447 cm-1 and 1540cm-1 of the mixture of pyridine and Fe-IL showed that Fe-IL presented the common acidic property of Bronsted acid and Lewis.A certain amount of Fe-IL was loaded into reactor and regenerator composed of glass sand funnel and glass tube, the H2S and O2 were respectively bubbled through the reactor and regenerator, and Fe-IL circularly flew through the reactor and regenerator. Based on the new Fe-IL a wet oxidation desulfurization process in an non-aqueous medium for hydrogen sulfide was established and investigated.The product sulfur was characterized by TQ XRD and FT-Raman. It is found that the sulfur capacity of Fe-IL is 0.31g/L and the desulfurization efficiency is high up to 96%, which depends on flow rate and concentration of hydrogen sulfide, reaction temperature and oxygen flow rate. The reaction temperature and flow rate of hydrogen sulfide put more significant influence on desulfurization efficiency. The desulfurization efficiency increased from 99.65% to 100% while the reaction temperature increased from 30℃to 50℃, and increased from 96.5% to 100% while the flow rate of hydrogen sulfide decreased from 60ml/min to 30ml/min. There was not a IR peak at 1622cm-1 assigned to S-O band, which implied that there were not by-products of SO42-,S2O32-,SO32- produced in this desulfurization process. The XRD and FT-Raman spectrum of the product sulfur showed that the product was monoclinic sulfur rather than orthorhombic sulfur from the traditional wet oxidation desulfurization in water.In general, the non-aqueous wet oxidation desulfurization process of hydrogen sulfide presents the following exciting advantages, such as no wastewater producing and no pH value controlling during desulfurization. It could be expected to be used as a green wet oxidation of desulfurization in chemical engineering and environmental engineering.
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