Residual oil hydrodesulfurization process

Claim 2

The process of claim 1, wherein the fresh catalyst is introduced as a catalyst slurry in a hydrocarbon oil boiling substantially above 350*C.

Claim 3

The process of claim 3, wherein hydrocarbon slurrying oil is selected from the group consisting of the residual hydrocarbon oil to be hydroprocessed, the hydroprocessed oil product and mixtures thereof and the fresh catalyst or slurry of fresh catalyst which is introduced into the reactor is at elevated temperature.

Claim 4

The process of claim 1, wherein the temperature is from 300* to 475*C, the total pressure is from 30 to 350 kg/cm2, the weight hourly space velocity is from 0.1 to 10 parts by weight of residual oil per part by volume of catalyst per hour, and the quantity of hydrogen supplied is from 10 to 10,000 Nl per kg of residual oil.

Claim 5

The process of claim 1, wherein a desulfurization level of at least 40%w is obtained.

Claim 6

The process of claim 1, wherein the residual oil flows upwardly through the catalyst bed and wherein the catalyst bed is brought in turbulent motion at least during the discharging procedure.

Claim 7

The process of claim 1, in which the residual oil has a sulfur content of at least 1.0 percent and a sodium content of less than 50 ppmw.

Claim 8

A substantially liquid phase continuous process for the hydrodesulfurization of a sulfur-containing residual hydrocarbon oil which comprises: a. Passing said oil and a hydrogen-containing gas co-currently through a reaction zone under hydrodesulfurization conditions, said reaction zone containing a substantially fixed-bed of hydrodesulfurization catalyst; b. Introducing fresh catalyst periodically at the top of the catalyst bed as required to maintain catalyst activity while passing said oil and hydrogen-containing gas through the reaction zone; c. Withdrawing spent catalyst periodically from the bottom of the catalyst bed as required to maintain a desired catalyst level in the reaction zone while passing said oil and hydrogen-containing gas through the reaction zone.

Claim 9

In the process of claim 9 wherein the reaction zone is a high-pressure vessel having a feed inlet and a product outlet and having connected to the top and bottom thereof by conduits a high-pressure vessel for containing fresh catalyst and a high-pressure vessel for receiving spent catalyst, respectively, wherein each conduit connecting the vessels is provided with at least one solids-handling valve; and wherein the fresh catalyst vessel contains at least one inlet for fresh catalyst and liquid and the spent catalyst vessel contains at least one outlet for spent catalyst and liquid; the improvement which comprises: a. Introducing an amount of fresh catalyst and liquid hydrocarbon oil into the fresh catalyst vessel at about the same temperature and pressure as that employed in the reaction vessel; b. Opening the solids-handling valves in the conduits connecting the reaction vessel to the fresh and spent catalyst vessels, thereby introducing fresh catalyst and liquid hydrocarbon oil to the top of the bed and withdrawing spent catalyst and liquid hydrocarbon oil from the bottom of the bed. c. Closing the solids-handling valves in said conduits when the desired amount of fresh catalyst has been added to the top of the substantially fixed catalyst bed and the desired amount of spent catalyst has been withdrawn from the bottom of said catalyst bed; d. Withdrawing spent catalyst and liquid hydrocarbon oil from the vessel for regeneration or disposal.