Phase equilibria of an ammonium ionic liquid with organic solvents and water

We report the phase diagrams of an ammonium ionic liquid: (benzyl)dimethylalkylammonium nitrate, [BA][NO3], where the alkyl is {C12H25 (w = 0.4) or C14H29 (w = 0.6)} with alcohols (propan-1-ol, butan-1-ol, hexan-1-ol, octan-1-ol, and decan-1-ol); with hydrocarbons (benzene, toluene, hexane, and hexadecane); and with water. The phase equilibria were measured by a synthetic method from 220 K to the melting point of the ionic liquid or to the normal boiling temperature of the solvent. Simple eutectic systems were observed for binary mixtures of [BA][NO3] with propan-1-ol and with butan-1-ol. The solid-liquid equilibria with immiscibility in the liquid phase for the ([BA][NO3] + water, hexan-1-ol, octan-1-ol, decan-1-ol, benzene, toluene, hexane, or hexadecane) are described. The difference of the solubility of the ionic liquid with longer chain alcohols is significant, a simple eutectic system was observed with immiscibility in the liquid phase for low mass fraction of the solvent. The upper critical solution temperature in binary mixtures of {[BA][NO3] + heptane or hexadecane} was limited by the boiling temperature of the solvent. For the systems evaluated, immiscibility of the liquid mixtures was observed up to a very high mass fraction of the ionic liquid.