Metal valorization from the waste produced in the manufacturing of Co/Mo catalysts: leaching and selective precipitation

• Published in: Journal of material cycles and waste management Vol. 21; no. 3; pp. 525 - 538
• Main Authors: Hamza, Mohammed F., Roux, Jean-Claude, Guibal, Eric
• Format: Journal Article
• Language: English
• Published: Tokyo Springer Japan 01.05.2019; Springer Nature B.V
• Subjects: Acids; Alkaline leaching; Catalysis; Catalysts; Civil Engineering; Cobalt; Engineering; Environmental Management; Heavy metals; Leachates; Leaching; Manufacturing; Manufacturing industry; Materials recovery; Metals; Molybdenum; Original Article; Poisoning; Precipitates; Sodium; Sulfides; Waste Management/Waste Technology; X-ray diffraction; Hydrodesulfurization catalyst; Alkaline leaching; Co and Mo selective recovery; Sulfide precipitation; Acidic leaching
• ISSN: 1438-4957; 1611-8227
• DOI: 10.1007/s10163-018-0811-9

Two different strategies have been designed for the acid and alkaline leaching steps of hydrodesulphurization catalysts. Tests have been performed on out-of-range catalysts issued from catalyst manufacturing process. Experimental conditions have been screened for these different processes considering the effects of concentration, temperature, solid/liquid ratio, etc. The best conditions have been used for producing two leachates that were treated by precipitation for recovery of valuable metals such as cobalt and molybdenum. Post-treatments have also been designed for the selective separation of Co from Mo: X-ray diffraction analyses on selective precipitates (as sulfide) confirm the purity of produced materials. Two flow sheets are proposed that allow selectively recovering more than 95% of the valuable metals.