Abstract: For the preparation of an ether, e.g., tertiary amyl methyl ether, an olefin-containing feed stream is catalytically etherified with an alcohol, e.g., methyl alcohol. The etherification product is fractionally distilled into an overhead fraction containing essentially unreacted, light hydrocarbons and unreacted alcohol and into a bottoms fraction containing essentially the desired ether. The overhead fraction is condensed and cooled to resultant immiscible phases, of which one contains essentially the alcohol and the other contains essentially the hydrocarbons, are removed separately from each other. Water may be added to the overhead stream to facilitate the formation of the two liquid phases.