Abstract: A process for hydrodesulfurization of heavy hydrocarbon oil containing asphaltenes and heavy metals in large amounts is disclosed. The heavy oil is hydrotreated in a continuous 2-step process. In the first step the heavy oil is subjected to hydrodemetallization and selective cracking of asphaltenes by the use of a catalyst having a unique selectivity therefor. In the second step the effluent from the first step is subjected to hydrodesulfurization to produce desulfurized oils of high grade by the use of a catalyst having a pore volume and pore size distribution particularly adapted for the hydrodesulfurization of the effluent.

Abstract: A method of softening or loosening caked catalyst pellets used for the desulfurization of a residual oil regardless of the sizes and shapes of the catalyst pellets and without the need of mechanically crushing the caked catalyst comprising contacting the caked catalyst with a washing oil containing an organic amine and/or ammonia gas absorbed therein.

Abstract: This invention relates to a catalyst for hydrotreatment of hydrocarbons comprising one or more of metals selected from the group consisting of transition metals and metals of group IIb of the periodic table supported on sepiolite. More particularly it relates to a catalyst effective in the selective demetallization treatment of hydrocarbons.