of u03b1 alumina particles 1 in nearly regular shape were arranged compactly and orderly as shown in fig1 wherein 1a represents a fine particle constituting the u03b1 alumina particle and 2 represents the carrier in the catalyst carrier obtained as described above comprising granular u03b1 alumina a great number of u03b1 alumina particles 1 in elongated shape intertwined with one another forming a network structure as shown in fig2 wherein 3 represents a void one kilogram of gibbsite al 2 o 3 3h 2 o which had been ground in a ball mill to a particle size of about 3 u03bc was added to 1 kg of gibbsite of a particle size of about 40 u03bc and mixed thoroughly to obtain the first material 270 grams of water was added in small portions with stirring to the first material and then thoroughly mixed in the same manner as described in example vi the mixture obtained above was granulated and the boehmite was transformed into u03b1 alumina which was sintered 308 grams of a 1 aqueous solution of methylcellulose was added to 2 kg of gibbsite which has been ground in a ball mill to a particle size of 3 u03bc and then thoroughly mixed in the same manner as described in example vi the mixture obtained above was granulated and the boehmite was transformed into u03b1 alumina which was sintered 270 grams of water was added to 2 kg of gibbsite which had been ground in a ball mill to a particle size of 3 u03bc and thoroughly mixed in the same manner as described.