Chemical Forums
Chemistry Forums for Students => Organic Chemistry Forum => Topic started by: polyol on July 01, 2004, 11:57:05 AM
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Ethylene glycol, C2H6O2, (1,2-ethanediol) is produced by the addition of an H3O+ ion to ethylene oxide, C2H40, (1,2-epoxyethane). The boiling point of ethylene glycol is 196-198C. When reagant grade ethylene glycol (>99.9% purity) is heated to 100-110C any H2O in the ethylene glycol is boiled out. Theoretically. should there any other gaseous products? Is this an efficient way of removing impurities from ethylene glycol? Ethylene glycol is mixed with a metal acetate, M(CH3CO2)n, (e.g. Co(CH3CO2)2) and rapidly heated using a 2.45 GHz microwave source to temperatures around 240C. The solution is under 30 PSI of pressure to prevent the solution from boiling. A proposed mechanism suggests that dehydration of ethylene glycol occurs with the rapid heating and acetaldehyde, C2H4O, (ethanal) along with water is produced. Acetaldehyde has a boiling point of 20.16C. The acetaldehyde reacts with metal acetate to produce nanopahse metal particles. In the presence of a metal oxide instead of a metal acetate, the acetaldehyde is oxidized to produce diacetyl, C4H6O2, (2,3-butanedione) water and the metal. Is diacetyl also formed when a metal acetate is used? Once the percipitate is centirfuged can the remaining solution be distilled/purified back to ethylene glycol? How is this accomplished?