Exceptionally effective H₂S absorption and conversion into thiols in novel superbase protic ionic liquids

Abstract

We demonstrate an effective strategy for capture and conversion of H 2 S in novel superbase protic ionic liquids (SPILs). It is found that the synthesized SPILs with the multiple active sites exhibit the unprecedented H 2 S uptake via chemical absorption (up to 1.81 mol mol À1 at 298.2 K and 1 bar). More importantly, H 2 S molecule is activated by these SPILs during the absorption process, so that the activated H 2 S can be converted further into high value-added thiols in situ with excellent yields under mild conditions (303.2 K and 1 bar) without any solvents and metallic catalysts. Since H 2 Ssaturated SPILs can be regenerated by chemical conversion of absorbed H 2 S into thiols, thereby eliminating the higher input of energy consumption during the process of H 2 S stripping. This SPIL-mediated scheme provides an alternative approach for the capture and chemical conversion of H 2 S.

Protic ionic liquids for sustainable uses

“…Upgrading of hydrogen sulfide into value-added products has also been studied in PILs. Liu et al 114 studied a series of super-base PILs, with 2,4,6-tris(dimethylaminomethylphenol) coupled with DBN being the most promising. The PIL was able to dissolve high amounts of hydrogen sulfide and transform it into a range of thiols in high yield under mild conditions at 30 °C.…”

Challenges of polymer‐based pH sensing in soil

“…While standard laboratory pH electrodes work well in that environment, they do not translate well into use in‐ground for many reasons. Liu et al point out that in‐ground measurements (for soil nitrogen sensing) using new sensor technology have rarely been attempted, as lab‐based validation is unsuitable for practical implementation 21 . For the broader soil and plant sensor market, Yin et al acknowledge the “immature reality of the sensor development and implementation” as one impediment to in‐ground real‐time sensing 4 .…”

Acidic protic ionic liquid‐based deep eutectic solvents capturing SO2 with low enthalpy changes

“…Ionic liquids (ILs), composed of cations and anions, have been emerging as a class of green solvents owing to their unique natures, such as low volatility, wide liquid range, and good affinity to gases 6 . Thus, investigation on gas capture using ILs has been a research hotspot, and a variety of gases were involved, including CO 2, 7–11 H 2 S, 12–14 NH 3, 15,16 SO 2, 17–20 CO 21–27 and so on 28,29 . Han et al reported the first case of SO 2 absorption using tetramethlyguanidium lactate ([TMG]L) IL, in which the SO 2 was bonded to [TMG] cation through S···N interaction 17 .…”

“…Ionic liquids (ILs), composed of cations and anions, have been emerging as a class of green solvents owing to their unique natures, such as low volatility, wide liquid range, and good affinity to gases. 6 Thus, investigation on gas capture using ILs has been a research hotspot, and a variety of gases were involved, including CO 2, 7-11 H 2 S, [12][13][14] NH 3, 15,16 SO 2, 17-20 CO [21][22][23][24][25][26][27] and so on. 28,29 Han et al…”