Kinetics of catalytic esterification of propionic acid with different alcohols over Amberlyst 15

Abstract

The kinetics of the esterification reaction between propionic acid and methanol, ethanol, and 1-butanol over the ion exchange resin, Amberlyst 15, was investigated. Experiments were conducted using a fixed-bed plug flow reactor over the temperature range of 298-328 K. Acid to alcohol molar ratios of 3:1, 1:1, and 1:3 were employed. For each esterification system, the equilibrium conversion of propionic acid was found to increase with increasing reaction temperature. Several kinetic models were tested to correlate the collected data under kinetically controlled conditions; the pseudo-homogeneous (P-H), Eley-Rideal (E-R), Langmuir-Hinshelwood (L-H), and Pöpken (P-P) models. In all cases, the activity coefficients were estimated using the UNIFAC model to account for the nonideal thermodynamic behavior of the reactants and products. The P-P model was found to best represent the kinetic data of the investigated esterification systems with a total average error of less than 3%. The increase of alcohol chain length had a negative impact on the conversion of propionic acid due to steric hindrance. The activation energy of the esterification reaction is influenced by the chain length of the alcohol used. The adsorption equilibrium constants estimated by the P-P model and the solubility parameters reported by AICHE DIPPER ® followed the same trend; ester < acid < alcohol < water.

Conversion improvement for catalytic synthesis of propylene glycol methyl ether acetate by reactive chromatography: Experiments and parameter estimation

“…The Van't Hoff plot is included as a supplementary material ( Figure S1). The value of ∆H is smaller than those reported in the studies of other esterification reactions, in which the final equilibrium depends on the temperature greatly [16]. From these observations, the experiments were designed and analyzed under the assumption that the effect of temperature is more crucial on the initial reaction rate than on the final conversion.…”

“…Some studies were focused on determining the model that gives the best prediction [16][17][18][19]. For the esterification reactions, several papers have reported that LangmuirHinshelwood model successfully predicted the experimental data [13,[20][21][22][23].…”

Kinetics of Transesterification of 1,4‐Butanediol With Methyl Acetate by the Ion‐exchange Resin

“… ER modelThe reaction that takes place between an adsorbed reactant molecule with a non‐adsorbed molecule from the bulk liquid to form an adsorbed molecule and a non‐adsorbed molecule can be known as the ER model. The key to use the ER model is to consider the components adsorption.It can be found from previous works that the compound with stronger polarity is more easily adsorbed on the catalyst surface . The polarity of ester and alcohol increases as the carbon chain shortens and the number of polar functional groups rises .…”

“…It can be found from previous works that the compound with stronger polarity is more easily adsorbed on the catalyst surface . The polarity of ester and alcohol increases as the carbon chain shortens and the number of polar functional groups rises .…”

“…The pseudo‐homogeneous (PH) and two adsorption‐based models (Langmuir–Hinshelwood [LH] and the Eley–Rideal [ER]) have been commonly used to describe the kinetics of heterogeneous catalytic reactions. The PH model is similar to the power‐law model for homogeneous reactions with no adsorption terms in the reactive system . The LH model points out that the reaction takes place between two adsorbed molecules in the active sites.…”