Author's Reply to Umland
Dr. Umland is correct in her preoccupation concerning the risk of explosion when distilling ether. The formation of unstable peroxides by oxidation of diethyl ether is well known and documented in the literature (1). Explosion can occur when the ether is distilled off and the residue, rich in peroxides, is heated to a higher temperature by the heating element.
In our experiment, described in the article (2), heating and distillation of the ether is done using previously heated hot water to prevent a fire hazard (see notes for the instructor in the supplemental material). Using this procedure, the ether is heated by warm water and the flask never reaches a high temperature. At the end of the distillation the flask still contains some ether along with a large amount of trimyristin. Under these conditions the risk of explosion is minimized even if the ether used initially contained peroxides.
We thank Dr. Umland for her comments and observations.
Literature Cited
- Hazards in the Chemical Laboratory; Bretheerick, L., Ed.; Royal Society of Chemistry: London, 1986; p 292; Roberts, R. M.; Gilbert, J. C.; Rodewald, L. B.; Wingrove, A. S. Modern Experimental Organic Chemistry, 4th ed; Holt Saunders International: Tokyo, 1995; pp 548-549.
- de Mattos, M. C. S.; Nicodem, D. E. J. Chem. Educ. 2002, 79, 94–95.
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