US Patent 7365228 Method for producing unsaturated fatty acids

Disclosed is a method for producing unsaturated fatty acids from unsaturated aldehydes by means of fixed-bed catalytic partial oxidation in a shell-and-tube reactor, characterized in that the reactor includes a reaction zone for producing unsaturated fatty acids, the reaction zone having an inactive material layer inserted into a position where a hot spot is to be generated in a reaction tube. A fixed-bed shell-and-tube reactor for use in the above method is also disclosed. According to the present invention, at least one layer of inactive material is packed at the point of a hot spot to control the hot spot temperature efficiently, thereby increasing the lifetime of a catalyst and producing unsaturated fatty acids with high yield.