The direct epoxidation of propene by molten salts

The epoxidation of propene using molten salts has been investigated. This m anner of direct propene epoxidation has been developed by Olin, claiming pr opene oxide selectivities of up to 65% at 15% propene conversion. A number of different molten salt mixtures were applied and several components were added in an attempt to increase selectivity. By comparing the epoxidation r esults in the molten salts to experiments using the same, but empty reactor s, an attempt was made to clarify the mode of operation of the salt. It was concluded that the salt acts as a catalyst in the formation of free radica ls, necessary for the homogeneous gas-phase oxidation taking place in the g as bubbles present in the molten salt medium. The salt, therefore, does not actually take part in the oxidation reaction, but only acts as an initiato r to the radical reaction process. (C) 2000 Elsevier Science B.V. All right s reserved.