KINETIC STUDIES FOR THE PRODUCTION OF ETHYL TERT BUTYL ETHER (ETBE) IN LIQUID PHASE UNLEAD GASOLINE ADDITIVES


Thesis Type: Postgraduate

Institution Of The Thesis: Gazi Üniversitesi, Fen Bilimleri Enstitüsü, Turkey

Approval Date: 2008

Student: FEYZA SARIÇAM

Supervisor: NURAY OKTAR

Abstract:

The aim of the present study is the synthesis of ethyl-tertiary butyl ether; an environmentally benign oxygenate employed as an additive in gasoline reformulation in order to reduce negative effects of transportation fuels on the ecosystem and human health. Ethanol and tert-butyl alcohol are used as reactants in this study. Ethanol as a renewable source and tert-butyl alcohol as a side product of the ARCO process played an important role in the production of this oxygenated compound. Besides, there haven't been any known harmful effect of ETBE on the other hand, MTBE was known to have harmful effects for human and environmental health which makes ETBE production preferable. In this study, liquid phase ETBE production was conducted in a packedcontinuous flow reactor, in the temperature range between 343–373 K, in the presence of acidic ion-exchange resin catalyst, namely Amberlit-15. In the study, effects of initial concentrations of tert-butyl alcohol and ethanol on ETBE conversion at different reaction temperatures were determined. Product conversions, reaction degree and reaction rate were calculated. An increase in ETBE conversion was observed with the increase in temperature. Initial TBA conversion was determined to have an insignificant effect on ETBE conversion. However, at temperatures over 353 K a decrease in ETBE conversion was observed. Evaluation of experimental data revealed an increase in reaction rate with increasing TBA initial concentration and temperature. Reaction degree in TBA basis was calculated close to ‘0.5' at high temperatures (363-373K) and ‘1' at low temperatures (343-353K). Activation energy of ETBE etherification reaction was calculated as 112.5 kJ/mol for low temperatures and 51.1 kJ/mol for high temperatures.