Kinetics of esterification

Determine whether the kinetics of esterification can be described by the second-order rate equation ... 

Krumpolc, M. and Malek, J., Esterification of benzenecarboxylic acids with ethylene glycol, III. Kinetics of esterification of 2-hydroxyethyl hydrogen terephthalate with ethylene glycol catalyzed by zinc oxide, Makromol. Chem., 168, 119-129 (1973). 

Based on experimental results and a model describing the kinetics of the system, it has been found that the temperature has the strongest influence on the performance of the system as it affects both the kinetics of esterification and of pervaporation. The rate of reaction increases with temperature according to Arrhenius law, whereas an increased temperature accelerates the pervaporation process also. Consequently, the water content decreases much faster at a higher temperature. The second important parameter is the initial molar ratio of the reactants involved. It has to be noted, however, that a deviation in the initial molar ratio from the stoichiometric value requires a rather expensive separation step to recover the unreacted component afterwards. The third factor is the ratio of membrane area to reaction volume, at least in the case of a batch reactor. For continuous opera-... 

The apphcations described here illustrate the wide range of uses for robotic systems. This chapter is not intended to he exhaustive there are many other examples of successful applications, some of which are referenced below. For instance, Brodach et al. [34] have described the use of a single robot to automate the production of several positron-emitting radiopharmaceuticals and TTiompson et al. [3S] have reported on a robotic sampler in operation in a radiochemical laboratory. Both of these apphcations have safety imphcations. CHnical apphcations are also important, and Castellani et al. [36] have described the use of robotic sample preparation for the immunochemical determination of cardiac isoenzymes. Lochmuller et al. [37], on the other hand, have used a robotic system to study reaction kinetics of esterification. 

Bart HJ, Reidetschlager J, Schatka K, Lehmann A (1994) Kinetics of esterification of levulinic acid with n-butanol by homogeneous catalysis. Ind Eng Chem Res 33 21-25... 

Since the Bart s research [1] was limited to one selected catalyst, it seemed reasonable to widen the work to other catalyst used in industry. The goal of this work was to learn about the kinetics of esterification of levulinic acid with 2-ethylhexanol using different catalysts, based on wide range of experiments in a semibatch reactor. 

Recent Developments on the Mechanism and Kinetics of Esterification Reaction Promoted by Various Catalysts... 

Many researchers have conducted a number of experiments to study the mechanism and kinetics of esterifications promoted by mineral acids (Cardoso et al., 2008). Summarizing recent research and development, esterification is an additive-eliminate course in the presence of mineral acid catalyst, generally complying with the following four typical and mature mechanisms. 

The esterification reaction of octanoic acid and n-octyl alcohol was carried out using CoCl2 2H20 as catalyst (0, 0.0385, 0.077 mol/1) at 70°C and the kinetic data were measured. The experimental curves suggest that the kinetics of esterification between octanoic acid and n-octyl alcohol can be described by an irreversible second order power model, considering the catalyst concentration as a constant in the kinetic model proposed. The activation energy is seen to have a value of 53 kcal/mol (Urteaga et al., 1994). 

The kinetics of esterification reaction can be expressed using a pseudo-homogeneous second-order equilibrium model in the absence of any intraparticle diffusional limitation as... 

The kinetics of esterification between acrylic acid and propylene glycol in the presence of Amberlyst 15 was investigated (Altiokka 6de , 2009). Taking into accoimt the general esterification reaction as well as polymerization of acrylic add and products, the overall reaction mechanism is proposed to be ... 

JagadeeshBabu, P. E., K. Sandesh M. B. Saidutta (2011) Kinetics of Esterification of Acetic Acid with Methanol in the Presence of Ion Exchange Resin Gatalysts. Industrial Engineering Chemistry Research, 50, 7155-7160,1SSN 0888-58851520-5045. 

Tiwari, N. S. Sawant (2005) Kinetics of Esterification of Erucic Add with Getyl Alcohol and Oleyl Alcohol. JOURNAL-OIL TECHNOLOGISTS ASSOCIAHON OE INDIA, 37,14,1SSN 0970-4094. 

Two separate series of experiments were carried out in order to study the reactivity of EPR-g-SA towards low Mw diols with or without the addition of a tertiary amine as catalyst, and the reactivity of EPR-g-SA towards a long-chain hydroxyl-terminated polybutadiene (HTPB). For both of them, the same experimental procedure was followed to ensure an intimate mixing of the reactants, they were all dissolved in a common solvent at room temperature and in a certain stoichiometric amount (in solution, the kinetics of esterification is very slow, thus the degree of reaction is negligible). Subsequently, the solvent is quickly removed by evaporation under vacuum at room temperature directly onto KBr disks to obtain a film which is used for IR analysis. 

Kinetics of esterification between organic acids and alcohols have been extensively studied. There are two different opinions about the ways in which performs its catalytic effect. One of the opinions is that the organic acid is activated initially, (Royals (1954)) i.e. the organic acid molecule gets a hydrogen ion from the catalyst before it is esterified with a molecule of primary or secondary alcohol. In the case of tertiary alcohol, such as t-butyl alcohol, the hydroxyl group of the alcohol, rather than that of the acid is eliminated. The other opinion was introduced by Goldschmidt... 

Dakshinamurty et al. (1992) studied the kinetics of esterification of n-propanol with acetic acid in a batch stirred tank reactor using a solid cation exchange resin, CXC 125 as a catalyst. He observed that the conversion of acid increased with increase in temperature, catalyst concentration and molar ratio of alcohol to acid. The reaction was found to be second order with respect to acid and zero order with respect to alcohol. An empirical correlation for the estimation of specific reaction rate constant was developed incorporating different variables studied. The Langmuir-Hinshelwood and Hougen-Watson models were used to determine the rate-controlling step. 

Venimadhavan et. al. (1999) developed batch reactive distillation model for production of butyl acetate in presence of sulfuric acid catalyst. They also studied the kinetics of esterification of acetic acid with butanol and calculated the thermodynamic equilibrium constant in a temperature range of 373 K- 393 K. They found that the equilibrium constant did not vary strongly with temperature. 

Kinetics of esterification of acetic acid with methanol to methyl acetate. 

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