Reactive distillation for synthesis of ethyl tertiary butyl ether on the ethanol and tertiary butanol on beta zeolite catalyst

Abstract

Synthesis of ethyl tert-butyl ether (ETBE) from the liquid phase reaction between ethanol (EtOH) and tert-butyl alcohol (TBA) was studied using commercially – available Amberlyst-15 and synthesized Beta zeolite. The catalytic activity of Amberlyst-15 was found to be higher than that of Beta zeolite. However, the selectivity to the product ETBE of Beta zeolite was much higher than that of Amberlyst-15. It was found that the yields to ETBE for both Amberlyst-15 and Beta zeolite were equivalent due to the higher selectivity of Beat zeolite. So it was concluded that Beta zeolite is more attractive than Amberlyst-15. The kinetic study of the reaction catalyzed by Beta zeolite was carried out using a batch reactor. The effect of external mass transfer was investigated by varying stirring speed. The rate law taking into account effect of water inhibition was developed. Three temperature levels of 323, 333 and 338 K were used in the study to obtain the parameters in the Arrhenius’s equation of the reaction rate constant and the van’t Hoff equation of the water inhibition coefficient. Reactive distillation, a configuration in which the catalyst section was located inside the distillation column, was employed to continuously synthesize ethyl tertiary butyl ether (abbreviated ETBE) from tertiary butanol (TBA) and bioethanol using Beta zeolite as catalyst. Results at standard operating conditions indicated that ETBE at 57 mol % could be obtained in the top product while almost pure water in the resideue. Other operating conditions such as heat duty, feed flowrate, reflux ratio and feed molar