초록 ▼

A process for recovering the metal values from spent hydroprocessing catalyst particles. The metal values will include at least one metal of Group VIII of the Periodic Table and at least one metal of Group Vb or Group VIb of the Periodic Table. The spent catalyst particles are first roasted at betwe

A process for recovering the metal values from spent hydroprocessing catalyst particles. The metal values will include at least one metal of Group VIII of the Periodic Table and at least one metal of Group Vb or Group VIb of the Periodic Table. The spent catalyst particles are first roasted at between 400°C. and 600°C. and then contacted with a first aqueous solution of ammonia and an ammonium salt forming a first pregnant liquor. The once-leached spent hydroprocessing catalysts are contacted with a second aqueous solution of sulfur dioxide forming a second pregnant liquor. The metal values are precipitated from the second pregnant liquor with hydrogen sulfide and the precipitate 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.

대표청구항 ▼

A process to recover the metal values from spent hydroprocessing catalyst particles, said values including: (i) at least one metal value selected from the Group consisting of cobalt and nickel; and (ii) at least one metal value selected from the Group consisting of vanadium, molybdenum and tungsten;

A process to recover the metal values from spent hydroprocessing catalyst particles, said values including: (i) at least one metal value selected from the Group consisting of cobalt and nickel; and (ii) at least one metal value selected from the Group consisting of vanadium, molybdenum and tungsten; comprising: (a) roasting the particles in an atmosphere containing molecular oxygen at a temperature in the range of between 400°C. and 600°C.; (b) leaching the particles with a first aqueous solution of ammonia and an ammonium salt at a temperature less than the atmospheric boiling point of said first aqueous solution, forming a first pregnant liquor and once-leached particles; (c) separating the once-leached particles from the first pregnant solution; (d) leaching the once-leached particles with a second aqueous solution containing sulfur dioxide, forming a second pregnant liquor and twice-leached particles; (e) separating the second pregnant liquor from the twice-leached particles; (f) precipitating metal sulfides from the second pregnant liquor by the addition of hydrogen sulfide; and (g) roasting said precipitated metal sulfides with fresh spent catalyst in step (a); (h) transferring said molybdenum, tungsten and vanadium metal values from said first pregnant liquor into a first organic solution by means of a first organic liquid extractant comprising a quaternary ammonium compound; (i) stripping said first organic solution with a first aqueous ammonium bicarbonate stripping solution to form an aqueous solution containing said molybdenum, tungsten and vanadium metal values; (j) transferring nickel values from said first pregnant liquor into a second organic solution by means of an organic nickel extractant comprising an oxime; (k) reducing cobalt metal values in said pregnant liquor to divalent cobalt; (l) transferring cobalt metal values from said pregnant liquor into a third organic solution by means of an organic cobalt extractant selected from the group consisting of dioximes, hydroxy-oximes, and beta-diketones; (m) stripping each of said second and third organic solutions with aqueous stripping solutions to form a cobalt-containing aqueous solution and a nickel-containing aqueous solution.