The paper aims to present a techno-economic analysis to recover nickel, molybdenum, and vanadium from spent hydrodesulfurization (HDS) catalysts. Some of these catalysts are wet because of residual naphtha or other hydrocarbon fractions, in a 5-13% concentration range. Others, instead, are dried and dusty, mainly containing coke and sulfur. Some are based on active metals like Ni-Mo, others on Co-Mo. The plant, with a 6000 tons/year capacity, is based on a industrial process with pre-treatment thermal stages tested on a pilot scale. In contrast, the hydrometallurgical section was studied at the University of L\\\'Aquila. The simulations were carried out using lab- and pilot-scale experimental data. Only wet Ni-Mo catalyst was used as the plant\\\'s feedstock, producing 1272 tons/year of V2O5 98%wt, 239 tons/year of MoO3 57%wt, and 227 tons/year of Ni-V-Mo alloy with an approximate composition of 72-25-3%wt, respectively. The investment is highly profitable, with a net profit of around 14.1 MEUR/year, gross margin of 37.2%, return on investment equal to 23.9%, and a payback time slightly greater than 4 years.

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