Spent catalysts removed from a catalytic hydrogenation process for hydrocarbon feedstocks, and containing undesired metals contaminants deposits, are regenerated. Following solvent washing to remove process oils, the catalyst is treated either with chemicals which form sulfate or oxysulfate compounds with the metals contaminants, or with acids which remove the metal contaminants, such as 5-50 W % sulfuric acid in aqueous solution and 0-10 W % ammonium ion solutions to substantially remove the metals deposits. The acid treating occurs within the temperature range of 60°-250° F. for 5-120 minutes at substantially atmospheric pressure. Carbon deposits are removed from the treated catalyst by carbon burnoff at 800°-900° F. temperature, using 1-6 V % oxygen in an inert gas mixture, after which the regenerated catalyst can be effectively reused in the catalytic process.

Catalyst regeneration process including metal contaminants removal

A process for removing metal contaminants from a hydroconversion catalyst, said catalyst containing at least one metal from Groups VIB, VIIB or VIII supported on a refractory inorganic oxide. The process comprises contacting the contaminated catalyst with a buffered oxalic acid solution wherein contaminant is removed without dissolving the support.

Removal of metal comtaminants from catalysts using buffered oxalic acid

Deactivated hydrorefining catalysts are regenerated by incorporation of as phosphorus component followed by combustive coke-removal from the catalyst. The regenerated catalyst is useful for promoting hydrodesulfurization reactions, particularly those involving demetallation of hydrocarbons.

Regeneration and reactivation of deactivated hydrorefining catalyst

Contacting deactivated hydrodesulfurization catalyst, such as Co-Mo supported on alumina, with a heteropoly acid, such as molybdophosphoric acid or tungstosilicic acid, to which dilute hydrogen peroxide is added, results in a significant enhancement in the rate and extent of carbon and metals removal. Forms of deposited vanadium intractable by other treatments are also removed. The process results in substantially complete regeneration of catalytic activity.

Regeneration of spent hydrodesulfurization catalysts with heteropoly acids and hydrogen peroxide

Spent catalysts removed from a catalytic hydrogenation process for hydrocarbon feedstocks, and containing carbon undesired metals contaminants deposits, are rejuvenated for reuse. Following solvent washing to remove process oils, the catalyst is treated either with chemicals which form sulfate or oxysulfate compounds with the metals contaminants, or with acids which remove the metal contaminants, such as 5-50 W % sulfuric acid in aqueous solution and 0-10 W % ammonium ion solutions to substantially remove the metals deposits. The acid treating occurs within the temperature range of 60°-250° F. for 5-120 minutes at substantially atmospheric pressure, after which the rejuvenated catalyst containing carbon deposits can be effectively reused in the catalytic hydrogenation process.

Catalyst rejuvenation process for removal of metal contaminants

PROCESS FOR REMOVING VANADIUM SULFIDE FROM USED HYDROTREATING CATALYST PARTICLES COMPRISING GROUP VI OR GROUP VIII METALS BY CONTACTING SAID CATALYST PARTICLES WITH AN AQUEOUS SOLUTION COMPRISING OXATILIC ACID BEFORE BURNING COKE FROM THE USED CATALYST PARTICLES

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Papers

Catalyst rejuvenation with oxalic acid