Hydrolysis kinetics of epoxypropyltrimethylammonium chloride in ethanol/water solution system

NaOH-based hydrolysis of epoxypropyltrimethylammonium chloride (ETA) was carried out in a batch reactor using ethanol/water system. The analytic technique, headspace-gas chromatography, was employed in order to follow the time evolution of ETA aqueous solution. Various effects on hydrolysis degree, such as, molar ratio of ethanol/water, NaOH concentration, reaction temperature, and dosage of hydrolysis product (2,3-dihydroxypropyl trimethylammonium chloride) were investigated. And then the kinetic model of the hydrolysis of ETA was developed and the possible mechanism of nucleophilic ring opening reaction was proposed. Furthermore, the model parameters of the process were also determined by data fitting. The results show that ETA hydrolysis follows the pseudo-first order law and kinetic model agrees well with the experimental results. Therefore, based on this kinetic model we could control the hydrolysis degree of ETA during ETA-involved cationic etherification of natural polymer in order to improve the etherification efficiency. (C) 2018 Institution of Chemical Engineers. Published by Elsevier B.V. All rights reserved.