Process Model of the Dependence of Yield and Energy Consumption on Temperature in the Production of Diethyl Ether from Ethanol
Fehim Zilić
*
INSPEKT RGH d.o.o. Sarajevo, Hamdije Kreševljakovića 18, Sarajevo, Bosnia and Herzegovina.
Husejin Keran
Faculty of Technology, University of Tuzla, Urfeta Vejzagića 8, Tuzla, Bosnia and Herzegovina.
Šejla Mešanović
Faculty of Technology, University of Tuzla, Urfeta Vejzagića 8, Tuzla, Bosnia and Herzegovina.
Selma Hasanović
Faculty of Technology, University of Tuzla, Urfeta Vejzagića 8, Tuzla, Bosnia and Herzegovina.
*Author to whom correspondence should be addressed.
Abstract
Diethyl ether (DEE) can be produced by acid-catalysed ethanol dehydration, but temperature affects reaction kinetics and thermal energy demand. This study aimed to develop a transparent process model describing the dependence of reaction rate, reaction time, target diethyl ether yield/conversion and thermal energy demand on reaction temperature for ethanol dehydration to diethyl ether. A stoichiometric and kinetic process-modelling study was conducted using the supplied Excel calculation model, with an Arrhenius temperature dependence and a pseudo-first-order conversion expression. The model uses a nominal production rate of 100 L/h of diethyl ether, a diethyl ether density of 0.713 kg/L, a target conversion/yield of 95%, an illustrative activation energy of 55 kJ/mol, and k120 = 0.020 min−1. Reaction time to 95% conversion is calculated from t95 = −ln(1−X)/k. Sensible heating demand and reaction heat are combined into a net thermal duty, and a specific net thermal duty is calculated per kilogram of diethyl ether. The calculated reaction-rate constant increases from 0.0200 min−1 at 120 °C to 0.0946 min−1 at 160 °C, while the time required to reach 95% conversion decreases from 149.79 to 31.67 min. The modelled target yield/conversion remains 95% throughout the range because it is prescribed as a model target. Net thermal duty increases from 3.215 to 5.618 kW, corresponding to an increase in specific net thermal duty from 0.0451 to 0.0788 kWh/kg DEE. The model demonstrates a clear kinetic–energy trade-off: higher temperature substantially accelerates the modelled reaction but increases thermal energy demand. The model does not establish an experimentally validated optimum because yield and selectivity were not measured and the kinetic and thermodynamic parameters are illustrative assumptions.
Keywords: Diethyl ether, ethanol dehydration, process model, reaction temperature, reaction time, energy consumption, Arrhenius equation, specific energy consumption