Greer Adam J, Taylor S F Rebecca, Daly Helen, Jacquemin Johan, Hardacre Christopher
Department of Chemical Engineering, The University of Manchester, The Mill, Sackville Street, Manchester M13 9PL, U.K.
Université de Tours, Laboratoire PCM2E, Parc de Grandmont, 37200 Tours, France.
ACS Sustain Chem Eng. 2022 Jul 25;10(29):9453-9459. doi: 10.1021/acssuschemeng.2c01848. Epub 2022 Jul 13.
Superbase ionic liquids (ILs) with a trihexyltetradecylphosphonium cation and a benzimidazolide ([P][Benzim]) or tetrazolide ([P][Tetz]) anion were investigated in a dual-IL system allowing the selective capture and separation of CO and SO, respectively, under realistic gas concentrations. The results show that [P][Tetz] is capable of efficiently capturing SO in preference to CO and thus, in a stepwise separation process, protects [P][Benzim] from the negative effects of the highly acidic contaminant. This results in [P][Benzim] maintaining >53% of its original CO uptake capacity after 30 absorption/desorption cycles in comparison to the 89% decrease observed after 11 cycles when [P][Tetz] was not present. Characterization of the ILs post exposure revealed that small amounts of SO were irreversibly absorbed to the [Benzim] anion responsible for the decrease in CO capacity. While optimization of this dual-IL system is required, this feasibility study demonstrates that [P][Tetz] is a suitable sorbent for reversibly capturing SO and significantly extending the lifetime of [P][Benzim] for CO uptake.
研究了具有三己基十四烷基鏻阳离子和苯并咪唑盐（[P][Benzim]）或四唑盐（[P][Tetz]）阴离子的超强碱离子液体（ILs）在双离子液体体系中的性能，该体系能够在实际气体浓度下分别选择性捕获和分离CO和SO₂。结果表明，[P][Tetz]能够优先于CO高效捕获SO₂，因此，在分步分离过程中，可保护[P][Benzim]免受高酸性污染物的负面影响。与不存在[P][Tetz]时11个循环后观察到的89%的下降相比，在30个吸收/解吸循环后，[P][Benzim]保持了其原始CO吸收能力的>53%。暴露后离子液体的表征显示，少量的SO₂被不可逆地吸收到导致CO容量下降的[Benzim]阴离子上。虽然需要对该双离子液体体系进行优化，但这项可行性研究表明，[P][Tetz]是一种适合可逆捕获SO₂并显著延长[P][Benzim]吸收CO寿命的吸附剂。
