KINETICS OF ESTERIFICATION OF LEVULINIC ACID WITH N-BUTANOL BY HOMOGENEOUS CATALYSIS

Kinetic data on the esterification of levulinic acid with n-butanol, catalyzed by sulfuric acid, have been obtained using a stirred batch reactor. Several experiments have been carried out with different initial molar ratios and different amounts of sulfuric acid at various temperatures. The conversion to n-butyl levulinate at 25-118-degrees-C follows a first-order rate expression with respect to each component. The resultant kinetic equation fitted the experimental data quite well and is given by the expression dc(C9H16O3)/dt = c(H2SO4)[286087e(-54275/RT)c(C5H8O3)c(C4H10O) - 15312e(-48431/RT)c(C9H16O3)c(H2O)]. Experiments have shown that DELTAH-degrees = 7.14 +/- 0.87 kJ mol-1, DELTAS-degrees = 78.6 +/- 2.1 J mol-1 K-1, DELTAH-1* = 51.4 +/- 0.4 kJ mol-1, and DELTAH-2* = 45.4 +/- 0.7 kJ mol-1. The equilibrium constants at 25, 50, 75, 90, and 100-degrees-C were found to be 0.33, 0.75, 1.50, 2.17, and 2.73, respectively.