Efficient conversion of H2S into mercaptan alcohol by tertiary-amine functionalized ionic liquids

This work develops a novel way of H2S resource into mercaptan alcohol mediated by tertiary-amine functionalized protic ionic liquids. [Display omitted] •Novel way of H2S resource utilization into mercaptan alcohol was developed.•The mechanism of H2S conversion mediated ionic liquids was proposed.•The reaction separation coupling process was proposed. The resource utilization of hydrogen sulfide (H2S) is of great significance in natural gas chemical industry. Described herein have developed a novel method mediated in tertiary amine-functionalized ionic liquids (ILs) to convert H2S into mercaptan alcohols with enols. The effect of ILs, substrate scope, and regeneration experiments have been investigated. It is found that the conversion of 3-methyl-2-buten-1-ol by H2S can reach 52% with a 50% (mol) catalyst loading of bis(2-dimethylaminoethyl) ether methoxyacetate within 12 h at 90 °C. The reaction mechanism was speculated based on theoretical calculation. Besides, a plausible reaction–separation-integrated strategy was further proposed. This work reveals an effective insight into the capture and catalytic conversion of H2S to high valuable mercaptan alcohol, which makes the utilization method of H2S resource universal and has the potentiality for industrial application.