HYDRODESULFURIZATION CATALYSTS BASED ON SUPPORTS PREPARED FROM REHYDRATABLE ALUMINA

A method of preparing hydrotreating catalysts for catalytic hydrodesulfurization of petroleum, having activated alumina supports, comprising; preparing a partially dehydrated, rehydratable alumina by flash calcining Bayer process hydrated alumina; rehydrating said partially dehydrated alumina with water which contains acid at pH below 7 at rehydration temperature, for the time needed for rehydration; solidifying the rehydrated alumina; mulling the solidified rehydrated alumina with sufficient water to make a mulled mixture suitable for particle forming, forming particles of desired size and configuration from the mulled mixture; drying the formed alumina particles and then calcining same by heating to calcining temperature; impregnating the calcined particles with liquid solutions of soluble compounds which are thermally decomposable to oxides of cobalt or nickel and to oxides of molybdenum or tungsten; and activating the impregnated alumina particles by calcining heat treatment to form hydrotreating catalysts.