Abstract: An improved process for the hydrodesulfurization of hydrocarbons employing a catalyst comprising Group VI-B and Group VIII metals supported on a refractory oxide and promoted with a minor amount of titanium by contacting the refractory oxide with an aqueous solution of a titanium salt.

Abstract: A shutdown procedure for residual hydrocarbon hydrodesulfurization process which employs a catalyst comprising Group VI-B and Group VIII metals, in sulfided form, supported on a refractory oxide and promoted with a minor amount of titanium.

Abstract: A process for hydrodesulfurizing a residual oil by passing the oil downwardly through a catalytic reaction zone at a hydrogen pressure which is sufficiently high that demetallization occurs rapidly so that at end-of-run the upstream catalyst region is more nearly metals-saturated than the downstream catalyst region. At the end of the catalyst cycle, the more nearly metals-saturated upstream portion of the catalyst is removed from the process while the less nearly metals-saturated downstream portion of the catalyst is passed to a guard chamber where during further operation of the process it approaches metals-saturation. In this manner, no portion of catalyst is removed from the process until it has an elevated metals content.