Experimental determination of viscosities and densities of mixtures carbon dioxide+1-allyl-3-methylimidazolium chloride. Viscosity correlation

Abstract

The effect of viscosity reduction caused by the solubilization of CO2 is studied in order to improve the biomass processing in ionic liquids. To do so, densities and viscosities of the pure ionic liquid 1-allyl-3-methylimidazolium chloride and its mixtures with CO2 up molar fractions of 0.25 and temperatures between 333 and 372 K have been experimentally determined. Viscosities were correlated as a function of temperature and CO2 molar fractions with an average relative error of 2.5%. The viscosities of other mixtures CO2 + ionic liquids were also correlated for other ionic liquids with an average relative error between 4.4 and 13%. In general these ionic liquids present a linear decrease of viscosity with CO2 molar fractions up to around 0.5 that is more pronounced at lower temperatures and depends of each ionic liquid, and can reach between 60-100% viscosi-2 ty reduction with respect the viscosity of the pure ionic liquid, making the CO2 a promising co-solvent for viscosity reduction in process with ionic liquids.

Ionic Liquid as Reaction Media for the Production of Cellulose-Derived Polymers from Cellulosic Biomass

“…To the best of our knowledge, only a few viscosity data of mixtures CO 2 + IL can be found in literature [124][125][126] for non-cellulose dissolving ILs, and for the mixture CO 2 + [Amim]Cl [127]. In general, the reduction in viscosity is between 85% and 45% at moderate pressures of 10-12 MPa, but with molar fractions as low as 10% of CO 2 , viscosity can decrease 30-40% with respect to the viscosity of the pure IL.…”

Solubility of CO2 in three cellulose‐dissolving ionic liquids

“…In this work, densities for the system CO 2 + [Emim][DEP] were obtained from Reference 20. For the system CO 2 + [Amim][Cl], densities were taken from Reference 11. For the system CO 2 + [Bmim][Cl], densities were approximated to those for the pure IL 30 .…”

“…Since solubility of IL into CO 2 is negligible, no contamination from the former is produced. Other additional advantage is that dissolved CO 2 in IL can improve its transport properties (i.e., reducing the viscosity) 11,12 or decreasing the melting point, 13,14 which enhances the liquid window. For example, Lopes et al 8 demonstrated that addition of CO 2 improves the kinetics of the acetylation of cellulose in allylmethylimidazolium chloride ([Amim][Cl]) as well as the quality of the product.…”

Determination of density, viscosity and vapor pressures of mixtures of dimethyl sulfoxide + 1-allyl-3-methylimidazolium chloride at atmospheric pressure

“…In addition, for binary mixtures of BmimCl with ethanol or water, the said properties were also determined at 298.15 K and atmospheric pressure. Lopes et al [15] studied the reduction in the viscosity of the ionic liquid AmimCl caused by dissolution of CO2.…”