Synthesis of ethyl ethanoate from ethanol by heterogeneous catalytic dehydrogenation, hydrogenation and purification

Abstract

A study has been carried out into the reactions of ethanol over transition metal dehydrogenation catalysts, with particular emphasis on the reaction of ethanol to ethyl ethanoate. The reaction is of commercial interest, and the test work has been aimed at the development of a process that would yield ethyl ethanoate at commercially acceptable purity. Copper based catalysts have been shown to selectively promote the formation of ethyl ethanoate. Experimental work has been carried out to identify an optimised catalyst and reaction conditions for the ethanol to ethyl ethanoate reaction. A copper based catalyst that yields >95% selectivity to ethyl ethanoate, at >40% conversion of ethanol, has been identified. A purification scheme has been devised that incorporates selective hydrogenation using either nickel or ruthenium heterogeneous catalysts to remove aldehyde and ketone by-products. The purification scheme includes a novel distillation section. The catalyst system developed can be used to synthesise ethyl ethanoate at a purity of >99.98% from industrially available ethanol that contains up to 5% 2-propanol. A commercial plant producing 50,000 tonnes of ethyl ethanoate per annum, using the technology described in this thesis, has been in operation since April 2001.Four patents, based on the technology described in this thesis, have been applied for or granted.