Process of producing olefin oxide

Claim 1

An electrochemical process of producing oxiranes of the formula ##STR4## wherein R 1 , R 2 and R 3 are substituents selected from the group consisting of hydrogen, methyl or ethyl and wherein the total amount of carbon atoms of R 1 , R 2 and R 3 is utmost 2, from olefins by means of an electrochemical system which consists of an anode, a cathode and an intervening partition and which is supplied with an alkali metal chloride-containing, aqueous electrolyte, wherein chlorinecontaining anolyte and olefin are reacted to form olefin chlorohydrin in a reaction chamber disposed outside the electrochemical system, a partial stream of the chlorohydrin-containing solution which leaves the reaction chamber is returned to the anode chamber of the electrochemical system, another partial stream and alkaline catholyte withdrawn from the electrochemical system are reacted to form oxirane and alkali chloride, the oxirane is removed from the solution and the latter is then returned to the anode and cathode chambers of the electrochemical system, characterized in that the electrolysis is carried out in an electrochemical system in which the anolyte and catholyte are separated by a membrane consisting of a cationpermeable polyfluorohydrocarbon which contains electronegative groups.