US 7,846,404 B2Granted

Process for separating and recovering base metals from used hydroprocessing catalyst

AssigneeChevron U.S.A. Inc.

InventorsRahul S. Bhaduri, John Stiksma, Roman Berezowsky

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Abstract

A method is disclosed for separating and recovering base metals from a used hydroprocessing catalyst originating from Group VIB and Group VIII metals and containing at least a Group VB metal. In one embodiment, the used catalyst is contacted with an ammonia leaching solution to dissolve and separate the Group VIB and VIII metals from the Group VB metal complex and coke associated with the used catalyst. The resulting Group VIB and VIII metal containing solution is processed through at least two additional precipitation and liquid/solid separation steps to produce, in separate processing streams, a Group VIB metal product solution (such as ammonium molybdate) and a Group VIII metal product solution (such as nickel sulfate). Additionally, two separate filtrate streams are generated from liquid-solid separation steps, which filtrate streams are combined and subjected to hydrolysis and oxidation (oxydrolysis) to generate a purified ammonium sulfate solution for further processing, such as for fertilizer.

Claims34

Dependent claims

A method of recovering metals from a used catalyst comprising the steps of:

(a) leaching a Group VB metal, a Group VIB metal and a Group VIII metal from the used catalyst with an ammonia containing leach solution at a temperature and a pressure sufficient to form a pressure leach slurry comprising at least a Group VIB soluble metal complex and at least a Group VIII soluble metal complex and a first solid residue;
(b) separating and removing the first solid residue from the pressure leach slurry to form a first pressure leach solution comprising the Group VIB soluble metal complex and the Group VIII soluble metal complex;
(c) precipitating from the first pressure leach solution a second solid residue comprising at least a portion of the Group VIB soluble metal complex to form a first slurry comprising the second solid residue and at least a portion of the Group VIII soluble metal complex;
(d) separating from the first slurry the second solid residue and a primary filtrate substantially free of Group VB, Group VIB and the Group VIII metals;
(e) dissolving the second solid residue to form a group VIB metal precipitate and a group VIII metal containing solution;
(f) separating the group VIB metal precipitate from the Group VIII metal containing solution of step (e);
(g) dissolving said Group VIB metal precipitate in a dilute base at a sufficient temperature to form a Group VIB metal product.

4 more elements

A method of recovering metals from a used catalyst originating from a hydroprocessing catalyst having a general formula (X)a(M)b[(CH3CH2)cN(CH3)3]dOz and containing at least a group VB metal, wherein X is a Group VIII non-noble metal, M is a group VIB metal selected from Mo and W and combinations thereof, c is an integer from 10 to 40, the molar ratio of a:b is from 0.5/1 to 3/1, the method comprising the steps of:

(a) leaching a Group VB metal, a Group VIB metal and a Group VIII metal from the used catalyst with an ammonia containing leach solution at a first selected pH and at a temperature and a pressure sufficient to form a pressure leach slurry comprising at least a Group VIB soluble metal complex and at least a Group VIII soluble metal complex and a first solid residue;
(b) separating and removing the first solid residue from the pressure leach slurry to form a first pressure leach solution comprising the Group VIB soluble metal complex and the Group VIII soluble metal complex;
(c) precipitating from the first pressure leach solution a second solid residue comprising at least a portion of the Group VIB soluble metal complex to form a first slurry comprising at least a portion of the Group VIII soluble metal complex;
(d) separating from the first slurry the second solid residue and a primary filtrate substantially free of Group VB, Group VIB and the Group VIII metals;
(e) dissolving the second solid residue to form a group VIB metal precipitate and a group VIII metal containing solution;
(f) separating the group VIB metal precipitate from the Group VIII metal containing solution of step (e) and
(g) dissolving said Group VIB metal precipitate in a dilute base at a sufficient temperature to form a Group VIB metal product.

4 more elements

Dependencies are inferred from the claim text.

Facts

Application: 12/340,404Filed 19 Dec 2008 · continuation in part
Priority: 28 Nov 2007
Published: US 2009/0133536 A128 May 2009
Granted: 7 Dec 2010
Term ends: Not estimatedThe source records don’t support an estimate.

Classification8 codes

C22B 7/008
Wet processes: by an alkaline or ammoniacal leaching
C22B 3/14
In inorganic alkaline solutions: containing ammonia or ammonium salts
C22B 7/009
Working up raw materials other than ores, e.g. scrap, to produce non-ferrous metals and compounds thereof; Methods of a general interest or…:…
C22B 23/0461
Treatment or purification of solutions, e.g. obtained by leaching: by chemical methods

Family

Application11/946,736Parent of this continuation-in-part · filed 28 Nov 2007
US 2009/0133536 A1Pre-grant publication · published 28 May 2009
US 7,658,895 B2Parent of this continuation-in-part
US 2009/0136399 A1Published application
US 7,846,404 B2This patent

From the US filing history. Foreign family members aren’t listed.