Esterifications in Ionic Liquids with 1-Alkyl-3-Methylimidazolium Cation and Hydrogen Sulfate Anion: Conversion and Phase Equilibrium

Abstract

The esterification of ethanol, 1-propanol and 1-butanol with acetic acid in three ionic liquids with HSO4 - anion and 1-alkyl-3-methylimidazolium cation was investigated. The ionic liquids are 1-methylimidazolium hydrogen sulfate [HMIM][HSO4], 1-ethyl-3-methylimidazolium hydrogen sulfate [EMIM][HSO4] and 1-butyl-3-methylimidazolium hydrogen sulfate [BMIM][HSO4], which have catalytic activity. Data and modeling on the reaction conversions and the distribution of the compounds between the phases is reported here. Trends for the change in the liquid-liquid equilibrium, with parameters like alkyl chain length on the cation or the alcohol, are discussed and used to estimate the phase behavior of similar esterification systems.