Reaction kinetics for synthesis of sec-butyl alcohol catalyzed by acid-functionalized ionic liquid

The acid-functionalized ionic liquid ([HSO3Pmim]HSO4) was synthesized by a two-step method. Nuclear magnetic resonance (NMR) and Fourier transform infrared spectroscopy (FT-IR) show that the synthesis method is feasible and high purity of ionic liquid can be obtained. Using [HSO3Pmim]HSO4 as the catalyst, we studied the reaction kinetics of synthesizing sec-butyl alcohol from sec-butyl acetate and methanol by transesterification in a high-pressure batch reactor. The effects of temperature, initial molar ratio of methanol to ester, and catalyst concentration on the conversion of sec-butyl acetate were studied. Based on its possible reaction mechanism, a homogeneous kinetic model was established. The results show that the reaction heat ΔH is 10.94 × 103 J·mol− 1, so the reaction is an endothermic reaction. The activation energies Ea + and Ea − are 60.38 × 103 and 49.44 × 103 J·mol− 1, respectively.

Graphical abstractThe effect of temperature on the reaction rate and conversion of SBAC was investigated at the molar ratio of MeOH to SBAC of 3.5 and catalyst concentration of 1.5% (by mass). The reaction rate and the conversion increase with temperature, while the equilibrium conversion at different temperatures changes slightly.Figure optionsDownload full-size imageDownload as PowerPoint slide