Electrochemical catalyst recovery method

An electrochemical method of recovering catalyst material from solid latent catalyst material comprising the following steps:

• combining latent catalyst material solids with a liquid acid anolyte solution and a redox material which is soluble in the acid anolyte solution to form an anolyte mixture;
• in an anode chamber of a minimum two chamber electrolytic cell, electrochemically oxidizing the redox material within anolyte the mixture into a dissolved oxidant, the oxidant having a potential for oxidation which is effectively higher than that of the latent catalyst material;
• reacting the oxidant with the latent catalyst material to oxidize the solid latent catalyst material into at least one oxidized species which dissolves within the anolyte mixture and to reduce the oxidant back into dissolved redox material;
• recovering catalyst material from the oxidized species of the anolyte mixture;
• and
• the latent catalyst material comprising copper chromite, and the dissolved oxidant comprising at least one of Ce.sup.4+, Ag.sup.2+, Co.sup.3+, and Mn.sup.3+.

An electrochemical method of recovering catalyst material from solid latent catalyst material comprising the following steps:

• combining solid latent catalyst material with a liquid acid anolyte solution and a redox material which is soluble in the acid anolyte solution to form an anolyte mixture;
• in an anode chamber of a minimum two chamber electrolytic cell, electrochemically oxidizing the redox material within the anolyte mixture into a dissolved oxidant, the oxidant having a potential for oxidation which is effectively higher than that of the latent catalyst material;
• reacting the oxidant with the solid latent catalyst material to oxidize the solid latent catalyst material into at least one oxidized species which dissolves within the anolyte mixture and to reduce the oxidant back into dissolved redox material;
• recovering catalyst material from the oxidized species of the anolyte mixture;
• and
• the latent catalyst material comprising copper chromite, the dissolved oxidant comprising cerium in the form of Ce.sup.4+, and the step of recovering including adding ammonium hydroxide to the mixture containing the oxidized catalyst species to precipitate cerium hydroxide out from such mixture;
• and recovering copper and chromium from the mixture out of which cerium hydroxide has precipitated.

An electrochemical method of recovering catalyst material from solid latent catalyst material comprising the following steps:

• combining solid latent catalyst material with a liquid acid anolyte solution and a redox material which is soluble in the acid anolyte solution to form an anolyte mixture;
• in an anode chamber of a minimum two chamber electrolytic cell, electrochemically oxidizing the redox material within the anolyte mixture into a dissolved oxidant, the oxidant having a potential for oxidation which is effectively higher than that of the latent catalyst material;
• reacting the oxidant with the solid latent catalyst material to oxidize the solid latent catalyst material into at least one oxidized species which dissolves within the anolyte mixture and to reduce the oxidant back into dissolved redox material;
• recovering catalyst material from the oxidized species of the anolyte mixture;
• and
• the latent catalyst material comprising copper chromite, the dissolved oxidant comprising silver in the form of Ag.sup.2+, and the step of recovering including adding hydrochloric acid to the mixture containing the oxidized catalyst species to precipitate silver chloride out from such mixture;
• and recovering copper and chromium from the mixture out of which silver chloride has precipitated

An electrochemical method of recovering catalyst material from reaction waste material solids, the reaction waste material solids comprising solid spent catalyst material having adhered reaction waste products, the method comprising the following steps:

• combining reaction waste material solids with a liquid acid anolyte solution and a redox material which is soluble in the acid anolyte solution to form an anolyte mixture;
• in an anode chamber of a minimum two chamber electrolytic cell, the anode chamber being defined by an electrolyte membrane barrier, electrochemically oxidizing the redox material within the anolyte mixture in the anode chamber into a dissolved oxidant, the oxidant having a potential for oxidation which is effectively higher than that of the spent catalyst material and adhered reaction waste products;
• reacting the oxidant with the solid spent catalyst material to oxidize the solid spent catalyst material into at least one oxidized species which dissolves within the anolyte mixture in the anode chamber and to reduce the oxidant back into dissolved redox material;
• reacting the oxidant with the adhered reaction waste products;
• and
• recovering catalyst material from the oxidized species of the anolyte mixture.

An electrochemical method of recovering petroleum hydroprocessing catalyst material from petroleum hydroprocessing reaction waste material solids, the waste material solids comprising solid spent catalyst material having adhered sulfides, carbon and hydrocarbons, the method comprising the following steps:

• combining petroleum hydroprocessing reaction waste material solids with a liquid acid anolyte solution and a redox material which is soluble in the acid anolyte solution to form an anolyte mixture;
• in an anode chamber of a minimum two chamber electrolytic cell, the anode chamber being defined by an electrolyte membrane barrier, electrochemically oxidizing the redox material within the anolyte mixture in the anode chamber into a dissolved oxidant, the oxidant having a potential for oxidation which is effectively higher than that of the spent catalyst material and adhered sulfides, carbon and hydrocarbons;
• reacting the oxidant with the solid spent catalyst material to oxidize the solid spent catalyst material into at least one oxidized species which dissolves within the anolyte mixture in the anode chamber and to reduce the oxidant back into dissolved redox material;
• reacting the oxidant with the sulfides to form anolyte mixture soluble forms of oxidized sulfur;
• reacting the oxidant with the hydrocarbons and with the carbon to form gaseous forms of oxidized carbon which are expelled from the anolyte mixture;
• and
• recovering catalyst material from the oxidized species of the anolyte mixture.