Determination And Calculation Of Viscosity And Surface Properties Of DEAE-Ionic Liquid Aqueous Solutions

The aim of this paper is to experimentally and theoretically investigate the viscosity and surface tensions of DEAE mixed with[Bmim][Gly],[Bmim][Lys]and[N₁₁₁₁][Gly]at different temperatures.The surface tension and viscosity of DEAE?diethylaminoethanol?-ionic liquid aqueous solution were measured in the temperature range of 303.2K-323.2K using BZY-1 automatic surface tension meter and NDJ-5S rotary viscometer respectively.TheDEAEmassfractionwas0.30-0.50.Threeionicliquid[N₁₁₁₁][Gly]?Tetramethylammoniumglycinesalt?,[Bmim][Lys]?1-butyl-3-methylimidazolide?and[Bmim][Gly]?1-butyl-3-methyl-imidazolide salt?are in the mass fraction of 0.025-0.075.Then,the thermodynamic equation suitable for expressing the surface tension and viscosity of the aqueous solution of DEAE-ionic liquid is proposed,and the surface tension and the viscosity is correlation predicted by the equation.The effects of temperature,DEAE and ionic liquid mass fraction on the surface tension and viscosity of the mixed system of DEAE-ionic liquid aqueous solution were elucidated on the basis of experimental and theoretical calculations.The results show:?1?The surface tension and viscosity of DEAE-ionic liquid aqueous solution decreased with the increase of temperature in the experimental range of temperature and mass fraction.When the temperature and the DEAE mass fraction(w_DEAE)were constant,the surface tension of DEAE-ionic liquid aqueous solution decreased with the increase of ionic liquid mass fraction,while the viscosity increased.When the temperature and ionic liquid mass fraction are constant,the surface tension of DEAE-ionic liquid aqueous solution decreased with the increase of the DEAE mass fraction(w_DEAE),while the viscosity increased.?2?The increase of temperature makes the surface tension of mixed aqueous solution decrease almost linearly,but the relationship between surface tension and ionic liquid mass fraction can not be described by linear function.?3?The differences of surface tension and viscosity between DEAE-[N₁₁₁₁][Gly],DEAE-[Bmim][Gly]and DEAE-[Bmim][Lys]aqueous solution are little.The surface tension of DEAE-[N₁₁₁₁][Gly]aqueous solution is slightly smaller than that of DEAE-[Bmim][Gly]and DEAE-[Bmim][Lys].The viscosity of DEAE-[N₁₁₁₁][Gly]aqueous solution is slightly lower than that of DEAE-[Bmim][Gly]aqueous solution,and the latter is slightly smaller than that of DEAE-[Bmim][Lys].?4?The proposed calculation model can accurately correlate and predict the surface tension and viscosity of DEAE-ionic liquid aqueous solution.The correlation prediction results are in good agreement with the experimental values.