Characterization Of Ionic Liquids And Their Application In NO₂ Absorption

In order to find an ionic liquid composite material with high NO₂ absorption,1-ethyl-3-methylimidazolium trifluoroacetate?EMIMTA?was prepared and its properties and application in flue gas denitrification were studied.The EMIMTA was characterized by FT-IR and1 NMR and was quantitative analyzed by UV.The results showed that water is a better solvent for quantitative analysis of EMIMTA with the maximum absorption wavelength of 210 nm.The EMIMTA-aqueous solution conforms the law of Beer-Lambert within the scope of 0.02 to 0.20 mg·m L^-1.The detection limit is 0.7 ug·mL^-1 and the recovery is 92.91-104.11%.The density and viscosity of EMIMTA and EMIMTA-triethanolamine?TEA?were measured at different temperatures?303.15 to 343.15 K?.The relation of the temperature and density of EMIMTA is in line with a linear equation while the relation of temperature and viscosity of EMIMTA is described by the VTF equation.Both of the correlation coefficients of the two equations are greater than 0.999.The excess molar volume?VE?and viscosity deviation????of EMIMTA-TEA solution were discussed.Results showed that the VE and ?? of EMIMTA-TEA solution and the molar ratio of EMIMTA are well fitted by a fourth order Redlich-Kister equation.The NO₂ absorption in EMIMTA and EMIMTA-TEA solution were dissucssed and the recycle of EMIMTA material and the absorption mechanism were studied.Results showed that the addition of TEA improved the NO₂ absorption in EMIMTA and the NO₂ absorptions in EMIMTA-TEA solution decrease with the increase of temperature.Recycle experiments showed that the ionic liquid can regenerate well and the NO₂ absorption remains the same.The absorption may probably follow a physical process.A EMIMTA mole ratio of 0.4091 was obtained by optimizing in which the NO₂ absorption is high while the viscosity is low.It is proved that the EMIMTA-TEA solution has a good application prospect as a NO₂ absorption agent.