Experimental Study on Factors Affecting the Recovery of Nickel fromSpent Catalyst

In this study, the recovery of nickel from spent NiMo/Al2O3 catalyst was investigated using 1 L stainless steel autoclave batch reactor. The effect of leaching process parameters such as temperature (40-80°C), time (1-4 h), pressure (1-3 bar), average particle size (69-550 μm) and agitation speed (400-600 min-1) on nickel extraction. The nickel percent in spent catalyst was found about 2.18%. The results obtained show that recovery of about 94% of nickel from spent catalyst was accomplished under the following conditions: temperature 80°C, pressure 1 bar, average particle size 200 μm, agitation speed 600 min-1, nitric acid concentration 40% and solid to liquid ratio1:50 after 4 h.