VIEIRA, A. G. F.; http://lattes.cnpq.br/7408567117245511; VIEIRA, Adrianna da Gama Fernandes.
Résumé:
The reaction of transformation of aqueous solution of ethanol for
production of acetone in the presence of massic catalysts composed of pure
zinc oxide, pure calcium oxide and steochiometric mixtures of them was studied
to optimize the conditions of preparation of these catalysts and the operational
characteristcs of this process, and also to propose a possible mechanism for
this reaction.
The synthesized catalysts were characterized by Chemical Analysis
(CA), X-ray diffraction (XRD), Specific Area (SA), Thermogravimetric and
thermodifferential Analysis (ATG/ATD) and isoeletric point measurement (IEP).
The catalytic activity of these catalysts was evaluated for the reaction of
hydrated ethanol with a catalytic test composed of a fixed bed glass
microreactor, into which the reagents were admitted vapours at a pressure
close to the equilibrium vapour pressure of the reactional mixture at ambient
pressure.
The results of this work show that catalysts based on chlorine salts are
more active and selective, for the formation of acetone, than those based on
nitrates, and that there is a strong correlation between the types of sites
(acidic/basic) found in these synthesized compounds and the orientation of the
reaction for the maximization of the production of acetone.
Finally, the reaction of formation of acetaldehyde is proposed as one of
the possible intermediate steps of the global reaction process.