Binary Brønsted Acidic Ionic Liquids (BBAILs) as the Reactive Extraction Intensified Catalysts for the Esterification of Acetic Acid and n-Butanol

Abstract

Reactive extraction for the esterification of n-butanol with acetic acid was studied using Binary Brønsted Acidic Ionic Liquids (BBAILs) as catalysts. Three [HSO₄] based Brønsted Acidic Ionic Liquids (BAILs) were prepared to formulate four bi-component ionic liquid catalysts. The effects of various parameters such as temperature, catalyst loading and catalyst formulation were investigated. The BBAILs were found to have not only good catalytic activity, but also good corrosion resistance and stability. Distribution coefficients were employed in these liquid–liquid biphase systems to interpret the reaction–separation intensification. The kinetics for the esterification of acetic acid with n-butanol using BBAILs as catalysts were also investigated systemically. A variant of the modified Langmuir–Hinshelwood–Hougen–Watson model (MLHHW) was used successfully to correlate the experimental kinetic data.