Reversible Autocatalytic Hydrolysis of Alkyl Formate: Kinetic and Reactor Modeling

Abstract

The kinetics and thermodynamics of alkyl formate hydrolysis in liquid phase were studied in a laboratory-scale autoclave at temperatures between 333 and 383 K using different molar ratios of the reactants. The process was found to exhibit an autocatalytic effect due to the acid formed. More so, the rate of neutral hydrolysis of ethyl formate is faster compared to methyl formate in the uncatalyzed reaction. However, the autocatalytic effect is more pronounced in methyl formate hydrolysis. In addition, the effect of adding a small amount of formic acid as an initial charge upon the equilibrium conversion and kinetics was investigated, and it was found that the addition improved the reaction rate by reducing the induction period but it suppressed slightly the equilibrium conversion. A kinetic model was proposed to explain these experimental trends, and the model agreed well with the experimental results.

Kinetic studies of alkyl formate hydrolysis using formic acid as a catalyst

“…The package combines the basics of thermodynamics with kinetic modelling. The UNIFAC parameters and the group interaction parameters are given in Jogunola et al 8 for both ethyl formate and methyl formate hydrolyses.…”

“…Salomaa7 studied the kinetics of alkyl formate hydrolysis in the presence of hydrogen chloride catalyst at 15–86 °C and suggested a mechanism for ester formation. Our group8 had earlier studied the kinetics and thermodynamics of both ethyl and methyl formate hydrolysis in neutral aqueous solution, as well as a detailed autocatalytic feature of the process. In addition, methyl formate hydrolysis using formic acid as a catalyst has been reported in patents as part of the methyl formate‐to‐formic acid production process 9, 10.…”

Theoretical study of the neutral hydrolysis of methyl formate via a concerted and stepwise water-assisted mechanism using free-energy curves and molecular dynamics simulation

“…Due to its small size, this ester has been employed as a test case in both experimental and theoretical investigations. Its hydrolysis has been extensively studied experimentally [12][13][14][15][16] and computationally [17][18][19][20][21], with the latter considering its catalysis in an alkaline medium [17][18][19], its simultaneous acid-base catalysis [20], and its neutral hydrolysis [21]. The reaction in a neutral aqueous medium, which is the case studied in the present work, leads to the formation of formic acid and methanol via different pathways.…”

Homogeneous Catalytic Kinetics of Methyl Glycolate Hydrolysis

“…A suitable kinetic model was developed with consideration of the dissociation contributions of SA and propionic acid, and the effect of the temperature on the dissociation constant is described by the empirical correlations quoted from the literature. Jogunola et al 17, 18 investigated the autocatalytic hydrolysis kinetics for the hydrolysis of alkyl formates. An empirical kinetic model containing a kinetic factor was proposed.…”

“…Hydroxonium ions are generally regarded as catalytic agent for hydrolysis 15, 16, 19, and the hydroxonium ion concentration depends on the temperature and the concentrations of the hydroxonium ion providers, such as the catalyst, water, and the GA generated by hydrolysis 16–19. In this work, the MG hydrolysis processes were investigated both in a stirred‐batch reactor and in a distillation column.…”