Metal recovery from spent Ni-Mo-V hydrodesulphurisation catalyst in oxalic acid media by mechanochemical treatment

The spent hydrodesulphurisation (HDS) catalysts used for the removal of sulphur from petroleum products can be a secondary source of especially Mo and V. This work describes the mechanochemical extraction of Mo, Ni, V, Al and P from spent petrochemical catalysts in H2C2O4. The effect of rotational speed, H2C2O4 concentration, ball to the dust weight ratio and solid-to-liquid ratio on the extraction rate of roasted spent catalyst was investigated. The reactions proceed with an increase in H2C2O4 concentration for extraction of Mo, V and P. The reactions for the extraction of Mo, V and P proceed with an increase in H2C2O4 concentration, but the dissolution behaviour of Ni is different from other elements. 87% of Mo, 44% of Ni, 82% of V, 36% of Al and 78% of P were extracted at optimum experimental conditions.

Automated summary

This study focuses on the mechanochemical extraction of Mo, Ni, V, Al, and P from spent hydrodesulphurisation (HDS) catalysts using H2C2O4. The extraction rate was influenced by rotational speed, H2C2O4 concentration, ball to dust weight ratio, and solid-to-liquid ratio. The reactions for Mo, V, and P extraction increased with H2C2O4 concentration, but the dissolution behavior of Ni was different. At optimum conditions, the extraction efficiencies reached 87% Mo, 44% Ni, 82% V, 36% Al, and 78% P.