| 摘要 |
<p>Metal values, including at least one metal of Group VIII and at least one metal of Group Vb or Group VIb of the Periodic Table, contained in spent hydroprocessing catalyst particles are recovered by first roasting the particles at between 400 and 600 DEG C and then leaching them with a first aqueous solution of ammonia and an ammonium salt to form a first pregnant liquor. The once-leached catalysts are leached with a second aqueous solution of sulfur dioxide forming a second pregnant liquor. The metal values are precipitated from this with hydrogen sulfide and this is roasted with unroasted spent hydroprocessing catalysts. The metal values of Group Vb and Group VIb in the first pregnant liquor are transferred into a first organic solution by liquid ion exchange. The first organic solution is stripped by an aqueous strip solution and the metal values separated by sequential precipitation. The metals of Group VIII are separated and purified by serial liquid ion exchange.</p> |
