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Title Extraction and Recovery of Metals from Spent HDS Catalysts: Lab- and Pilot-Scale Results of the Overall Process
ID_Doc 24270
Authors Xhaferaj, N; Ippolito, NM; Maggiore, F; Ferella, F
Title Extraction and Recovery of Metals from Spent HDS Catalysts: Lab- and Pilot-Scale Results of the Overall Process
Year 2022
Published Metals, 12, 12
DOI 10.3390/met12122162
Abstract The present study proposes an overall recycling process for spent hydrodesulfurization (HDS) catalysts. These catalysts contain valuable metals like cobalt (Co), molybdenum (Mo), nickel (Ni), and vanadium (V). In particular, one Co-Mo catalyst was treated in order to optimize the roasting step (time, soda ash, and temperature) at a pilot scale and thus maximize the extraction yield of molybdenum (Mo) and vanadium (V). In particular, a dry Co-Mo catalyst was used. After roasting at 700 degrees C for 2.5 h, the best conditions, the catalysts underwent water leaching, separating Mo and V from Co and the alumina carrier, which remained in the solid residue. The pregnant solution was treated to remove arsenic (As) and phosphorus (P), representing the main impurities for producing steel alloys. V was precipitated as NH4Cl, and further calcined to obtain commercial-grade V2O5, whereas Mo was recovered as molybdic acid by further precipitation at a pH of around one. Thus, molybdic acid was calcined and converted into commercial-grade MoO3 by calcination. The hydrometallurgical section was tested on a lab scale. The total recovery yield was nearly 61% for Mo and 68% for V, respectively, compared with their initial concentration in the spent Co-Mo catalysts.
Author Keywords catalyst; molybdenum; vanadium; cobalt; hydrodesulfurization; HDS; recycling; circular economy
Index Keywords Index Keywords
Document Type Other
Open Access Open Access
Source Science Citation Index Expanded (SCI-EXPANDED)
EID WOS:000902704100001
WoS Category Materials Science, Multidisciplinary; Metallurgy & Metallurgical Engineering
Research Area Materials Science; Metallurgy & Metallurgical Engineering
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