Simultaneous Removal of NO and SO(2) from Flue Gas Using [Bmim](2)FeCl(4)/Sulfolane Binary Mixtures

[Image: see text] NO and SO(2) are the major pollutants of coal combustion. As superior absorbents, ionic liquids are environmentally friendly, are reusable, and can clean flue gases, such as CO(2), SO(2), and NO(x). However, NO and SO(2) absorption with low concentration in flue gases under normal conditions is rarely studied. In this work, [Bmim](2)FeCl(4) was synthesized and mixed with sulfolane for NO and SO(2) removal from flue gas. The investigated concentrations of NO and SO(2) were 1100 and 2500 ppm, respectively, which are close to real fuel gas conditions. Results showed that 30 wt % [Bmim](2)FeCl(4)/sulfolane mixture performed the best absorption behavior. The presence of SO(2) could promote NO absorption by [Bmim](2)FeCl(4)/sulfolane mixture. The 30 wt % [Bmim](2)FeCl(4)/sulfolane mixture had removal efficiencies of 93.6 and 76.2% for NO and SO(2), respectively. This mixture also showed great reusability for NO and SO(2) after six cycles of absorption. Fourier transform infrared (FTIR) spectrum indicated that SO(2) and NO removal by [Bmim](2)FeCl(4)/sulfolane binary mixture was due to the chemical reaction between NO and [Bmim](2)FeCl(4) and the physical absorption between SO(2) and sulfolane.