An anisotropic structured fixed-bed divided into 2 reactor parts is a bundle reactor consisting of fiber-bundle. The fiber-bundle ordered in the flow direction are formed from filaments; the diam. of the fiber-bundle is smaller than its length and bigger than its interspace diam. A catalyst is deposited on the fiber-bundle. The reactor is esp. suitable for catalytic dehydrogenation of propane to propene with oxygen. [on SciFinder (R)]