The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
May. 22, 1990
Filed:
Jun. 26, 1985
Paul J Marcantonio, Novato, CA (US);
Chevron Research Company, San Francisco, CA (US);
Abstract
A process is disclosed to extract metal values selected from the group consisting of cobalt, molybdenum, nickel, tungsten, and vanadium from metal-containing particles, such as spent hydroprocessing catalyst particles containing carbon residue. In this process, the spent catalyst particles are roasted in an oxygen-containing gas at a temperature of from 400.degree. C. to 600.degree. C., and then the roasted catalyst particles are contacted with an aqueous solution of ammonia, ammonium salt, and hydrogen peroxide. That aqueous solution has an initial pH of at least 9.5 and an initial hydrogen peroxide concentration of from 0.02 to 0.2 M. That aqueous solution is maintained at a pH of greater than 9.5.