Esterification reaction kinetics of acetic acid and n‐pentanol catalyzed by sulfated zirconia

Abstract

This study reports experimental data and kinetic modeling of acetic acid esterification with n‐pentanol using sulfated zirconia as a catalyst. Reactions were carried out in an isothermal well‐mixed batch reactor at different temperatures (50‐80°C), n‐pentanol to acid molar ratios (1:1‐3:1), and catalyst loadings (5‐10 wt% in relation to the total amount of acetic acid). The reaction mechanism regarding the heterogeneous catalysis was evaluated considering pseudo‐homogeneous, Eley–Rideal, and Langmuir–Hinshelwood model approaches. The reaction mixture was considered a nonideal solution and the UNIQUAC thermodynamic model was used to take into account the nonidealities in the liquid phase. The results obtained indicated that increases in the temperature and catalyst loading increased the product formation, while changes in the n‐pentanol to acetic acid molar ratio showed no significant effect. The estimated enthalpy of the reaction was −8.49 kJ mol−1, suggesting a slightly exothermic reaction. The Eley–Rideal model, with acetic acid adsorbed on the catalyst as the limiting step, was found to be the most significant reaction mechanism.

Role of Sulfation of Zirconia Catalysts in Vapor Phase Ketonization of Acetic Acid

“…Sulfated zirconia (SZ) is well established as a robust and efficient solid acid catalyst for a variety of reactions of high industrial importance, such as hydrocarbon isomerization, methanol conversion to hydrocarbons, alkylation, acylation, esterification, dehydration, and Fischer–Tropsch processes. − More recently, sulfated zirconia has also emerged as a promising catalyst for several biorefinery processes, such as esterification, biodiesel preparation, − furfural synthesis − and conversion, − condensation of ketones, glycerol utilization, − and, conversion of CO 2 to light olefins . Among the biorefinery processes, the upgrading of biomass derived volatile fatty acids (C 3 –C 6 ) to corresponding ketones (ketonization reactions) is a promising strategy for the synthesis of biofuels.…”

Kinetic Modeling of scCO2-Assisted Levulinic Acid Esterification with Ethanol Using Amberlyst-15 as a Catalyst in a Batch Reactor

“…Both the non-isothermal approach, as well as the v-T flash calculations, are further described. In this work, the reaction rate is represented using an activity-based Langmuir−Hinshelwood rate law, considering that the surface reaction is the rate-controlling step, 19 according to eqs 3−5, 15 ) eq eq R 1 1…”

“…In this work, the reaction rate is represented using an activity-based Langmuir–Hinshelwood rate law, considering that the surface reaction is the rate-controlling step, according to eqs –, where k° and K eq ° are the kinetic and equilibrium constants at a reference temperature, E a is the activation energy, R is the universal gas constant, T is the temperature, Δ H R is the reaction enthalpy, which is assumed as constant in this formulation, K ads, i is the adsorption constant of each i component, and a i is the activity of each i product or reactant. In an isofugacity approach ( ϕ–ϕ ), the activity of a given component in a mixture in a specific phase is defined as (eq ): where x i and γ i are the mole fraction and activity coefficient of a certain component, respectively, and ϕ̂ i and ϕ i are the fugacity coefficients of a component in a mixture and as a pure component at the same temperature and pressure.…”

Kinetic Parameters Investigation for The Esterification of Free Fatty Acid from Coconut Oil Mill Waste using Montmorillonite-Sulfonated Carbon from Glucose Composite Catalyst

“…An important structural attribute of a catalyst is related to the rate of the esterification reaction. Several esterification kinetic studies have been reported using various feedstocks and catalysts (Gao et al, 2020;Hamerski et al, 2020;Kusumaningtyas et al, 2017;. The previous study employed the zeolite-sulfonated biochar derived from biomass-based such as molasse for the catalytic esterification of FFA derived from sludge palm oil.…”