A novel method of using anion-functionalized ionic liquids (ILs) with high NO absorption capacity and reversibility for the capture and in situ oxidation of low-concentration NO was established. For the mixed gas containing 0.25% NO, the accumulation rate of nitric acid in these ILs was significantly higher than that in the conventional ILs; after absorption and oxidation reached equilibrium, the molar ratio of HNO 3 to [P 4446 ][PhSO 3 ] was 0.86, which was 5 times as high as that of the conventional IL. Therefore, the problems of low efficiency and poor reversibility of traditional ILs in the absorption and oxidation process were solved. Through absorption and oxidation experiments, quantum chemical calculation, NMR, and time-resolved in situ ATR-FTIR spectroscopic investigation, the results demonstrated that such a high accumulation rate of HNO 3 originated from high uptake of NO through multiple-site interaction. Moreover, high reversibility is attributed to low volatility of conjugated acid of anions and decreased basicity of O sites on anions. We believe that such highly efficient and reversible conversion of low-concentration NO to HNO 3 by ILs provides a new strategy for improving atomic economy of fossil fuel combustion, that is, converting post-combustion pollutants to good valuable chemicals.

A cation-tunable strategy was reported for highly selective absorption of low-concentration SO2 over CO2 in flue gas, where the cation had a significant effect on the selectivity. The absorption capacity and selectivity of low-concentration SO2 by various ionic liquids (ILs) were investigated; therein, protic IL [THEEDH][Tetz] showed the best selectivity of 80.6 (120.4) under the atmosphere of 2000 ppm of SO2 and 15% CO2. Nuclear magnetic resonance spectroscopic investigations and quantum chemical calculations indicated that the effect of the cation on the electronegativity of the anion was significant, leading to an obvious increase in selectivity. This cation-tunable IL offered a significant improvement in the selective absorption of SO2 compared to traditional ILs, indicating its potential in acid gas separation in industry.

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Through computer-assisted design, a multiple hydrogen bonding catalyst was developed to achieve efficient hydration of epoxides under mild temperature and atmospheric pressure, eliminating the use of metal. Through the introduction...

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