Method for recovering valuable metals in waste residue oil hydrogenation catalyst

Abstract

The invention belongs to the technical field of waste catalyst recovery, and particularly relates to a method for recovering valuable metals in a waste residue oil hydrogenation catalyst, which comprises the following steps: (1) mixing choline chloride and benzenesulfonic acid monohydrate to obtain a eutectic solvent system; (2) grinding and drying the waste residue oil hydrogenation catalyst to obtain waste catalyst powder; mixing the waste catalyst powder with a deep eutectic solvent system, and reacting at 50-90 DEG C for 2-6 hours, wherein the waste residue oil hydrogenation catalyst is a mixture of a composite metal oxide Ni (MoO4) and MoV2O8; and (3) centrifuging the reaction solution obtained in the step (2) to obtain a leachate containing Mo ions, Ni ions and V ions. The valuable metal recovery method has a good recovery effect on Mo, V and Ni, the leaching efficiency of Mo is close to 100%, the leaching efficiency of Ni and V is also larger than 90%, the leaching temperature is low, and the leaching time is short.

Description

Technical Field

[0001] The invention belongs to the technical field of waste catalyst recovery, and particularly relates to a method for recovering valuable metals in waste residual oil hydrogenation catalysts. Background Art

[0002] With the development of the chemical industry, especially the development of chemical industries such as oil refining and chemical industry that use a large amount of catalysts, a large amount of waste catalysts will be generated. At the same time, with the increasingly stringent environmental regulations, the treatment of these waste catalysts has become an important problem.

[0003] A large amount of spent hydrogenation catalysts are produced during the petroleum refining process. These catalysts contain a large amount of useful metals such as Mo, V, and Ni, and are important secondary resources.

[0004] Due to economic and environmental considerations, the recovery of metals from secondary resources is gaining attention. In order to reduce the amount of spent catalysts produced and prevent environmental pollution, it is necessary to recycle spent catalysts. Pyrometallurgy and hydrometallurgy are the two main methods for catalyst recycling. Despite this, the use of traditional technologies still faces practical challenges. The pyrometallurgical route has high energy consumption. The selectivity of inorganic acids and alkaline solutions in the hydrometallurgical route is low, resulting in contamination of the leaching solution. Since both pyrometallurgical and hydrometallurgical methods have environmental problems, it is crucial to develop alternative processes that can meet both efficient leaching and reduce environmental risks. The Mo, V, and Ni metal oxides in these catalysts mainly exist in the form of composite metal oxides Ni (MoO4) and MoV2O8. Compared with layered oxides (metals mainly exist in the form of simple cations), the leaching of metals from waste residue oil hydrogenation catalysts is difficult.

[0005] Deep eutectic solvents, a new type of green solvent, are composed of two or more components that form a eutectic system through hydrogen bonding, resulting in a lower melting point than a single component. These solvents not only possess low toxicity, a wide liquid phase range, high thermal stability, and designability, but also exhibit broad application prospects in metal resource recovery due to their simple preparation process, readily available raw materials, and low cost. Therefore, it is necessary to design deep eutectic solvents suitable for the recovery of metal resources from spent hydrogenation catalysts. Summary of the Invention

[0006] In view of the problems and shortcomings in the prior art, the present invention aims to provide a method for recovering valuable metals in waste residue oil hydrogenation catalysts.

[0007] In order to achieve the purpose of the present invention, the technical solution adopted by the present invention is as follows:

[0008] The present invention provides a method for recovering valuable metals in a waste residue oil hydrogenation catalyst, comprising the following steps:

[0009] (1) mixing choline chloride and benzenesulfonic acid monohydrate to obtain a deep eutectic solvent system;

[0010] (2) grinding and drying the waste residue oil hydrogenation catalyst to obtain a waste catalyst powder; mixing the waste catalyst powder with a low eutectic solvent system and reacting at 50 to 90° C. for 2 to 6 hours, wherein the waste residue oil hydrogenation catalyst is a mixture of composite metal oxides Ni(MoO4) and MoV2O8;

[0011] (3) Centrifuging the reaction solution obtained in step (2) to obtain a leachate containing Mo ions, Ni ions and V ions.

[0012] Preferably, the leachate in step (3) contains molybdate ions MoO4 2- , polymolybdate ions, divalent nickel ions Ni 2+ 、Vanadium ion VO2 + , polyvanadate ion leachate

[0013] Polymolybdate ions and polyvanadate ions may exist as a single ion or a mixture of multiple ions, in which the polymolybdate ions are mainly Mo7O 24 6- and Mo8O 26 4- The polyvanadate ions are mainly V6O 19 8- and V 10 O 28 6- .

[0014] Preferably, the molar ratio of choline chloride to benzenesulfonic acid monohydrate in step (1) is (1-2):(1-3).

[0015] More preferably, the molar ratio of choline chloride to benzenesulfonic acid monohydrate in step (1) is 1:3.

[0016] Preferably, in step (2), the ratio of the spent catalyst powder to the low eutectic solvent system is (10-50) g:1 L.

[0017] More preferably, the ratio of the waste catalyst powder to the low eutectic solvent system in step (2) is 20 g:1 L.

[0018] Preferably, the reaction temperature in step (2) is 70° C. and the reaction time is 5 h.

[0019] Preferably, in step (2), the waste residue oil hydrogenation catalyst is ground to a particle size of 0.45 mm.

[0020] Preferably, the reaction solution is centrifuged in step (3) at a rate of 8000-9000 rpm for 10-20 min.

[0021] Compared with the prior art, the present invention has the following advantages:

[0022] (1) The waste oil hydrogenation catalyst of the present invention mainly exists in the form of composite metal oxides Ni (MoO4) and MoV2O8. After leaching, the metal is mainly in the form of MoO4 2- 、Polymolybdate ions (Mo7O 24 6- or Mo8O 26 4- ), Ni 2+ , VO2 + 、Polyvanadate ion (V6O 19 8- or V 10 O 28 6- ) exists, the present invention uses a binary deep eutectic solvent system formed by choline chloride and benzenesulfonic acid monohydrate to effectively and simultaneously recover Mo, V, and Ni in one go, with high recovery efficiency. Furthermore, the present application eliminates the need for strong acidic or alkaline leaching processes, eliminating the need for corrosive acids and bases to overcome the limitations of previous hydrometallurgical technologies, thereby minimizing equipment corrosion and reducing environmental impact by minimizing wastewater generation.

[0023] (2) The valuable metal recovery method of the present invention has a good recovery effect on Mo, V and Ni. Under the action of the low eutectic solvent of the present invention, the Mo leaching efficiency is close to 100%, and the Ni and V leaching efficiencies are also greater than 90%. In addition, the leaching temperature is low and the leaching time is short. BRIEF DESCRIPTION OF THE DRAWINGS

[0024] Figure 1 is the X-ray diffraction (XRD) pattern of waste residue oil hydrogenation catalyst;

[0025] Figure 2 The present invention is a flow chart for recovering valuable metals from waste residue oil hydrogenation catalyst;

[0026] Figure 3 The leaching rate diagram of Mo, Ni and V by different deep eutectic solvents;

[0027] Figure 4 This is a comparison chart of the leaching rates of choline chloride, benzenesulfonic acid monohydrate, and deep eutectic solvent. DETAILED DESCRIPTION

[0028] The X-ray diffraction (XRD) pattern test of the waste residue oil hydrogenation catalyst of the present invention is as follows Figure 1 As shown by Figure 1It can be seen that the waste catalyst of the present invention mainly exists in the form of composite metal oxides Ni (MoO4) and MoV2O8. The waste residue oil hydrogenation catalyst mainly contains metals Mo and V. After leaching, it mainly exists in the form of MoO4. 2- 、Polymolybdate ions (Mo7O 24 6- or Mo8O 26 4- ), VO2 + 、Polyvanadate ion (V6O 19 8- or V 10 O 28 6- )exist.

[0029] Example 1

[0030] A method for recovering valuable metals from waste oil hydrogenation catalyst, the process is as follows Figure 2 As shown, the specific steps are:

[0031] (1) Choline chloride and benzenesulfonic acid monohydrate were mixed in a molar ratio of 1:3, and stirred at 70°C for 30 minutes by heating in a water bath to obtain a uniform solution, which is a deep eutectic solvent (DES);

[0032] (2) Grinding the waste oil hydrogenation catalyst to a particle size of 0.45 mm and drying at 60° C. to obtain a waste catalyst powder; adding 0.1 g of the waste catalyst powder to 5 mL of the low eutectic solvent of step (1); reacting in a constant temperature water bath at 70° C. for 5 h to obtain a reaction solution;

[0033] (3) The obtained reaction solution is centrifuged at a centrifugal rate of 8000 rpm for 20 min to obtain a leachate containing valuable metals.

[0034] The valuable metal leaching rate in Example 1 was determined by first determining the metal content in the waste residual oil hydrogenation catalyst. The specific steps were as follows: 0.1g of the waste residual oil hydrogenation catalyst was mixed with 10mL of aqua regia and 3mL of hydrofluoric acid and digested at 120°C for 2h. After the digestion solution was free of solid particles, the acid was removed. The digestion solution was then transferred to a 100mL volumetric flask and brought to volume. The solution in the volumetric flask was then diluted 25-fold. Atomic absorption spectrometry determined the solution to have a Mo concentration of 12.71mg / L, a Ni concentration of 1.913mg / L, and a V concentration of 6.639mg / L.

[0035] The calculated contents of main elements in waste residue oil hydrogenation catalyst are shown in Table 1.

[0036] Table 1 Metal element content in waste residue oil hydrogenation catalyst

[0037] element Mo Ni V content% 31.78 4.78 16.60

[0038] 200 μL of the leachate of Example 1 was diluted 250 times with deionized water. The concentrations of Mo, Ni, and V in the solution were measured by atomic absorption spectrometry to be 25.22 mg / L, 3.47 mg / L, and 12.43 mg / L, respectively. The leaching rate of valuable metals was further calculated based on the metal element content in the waste residue oil hydrogenation catalyst. The leaching rates of Mo, Ni, and V were calculated to be 99.21%, 90.70%, and 93.61%, respectively.

[0039] Example 2

[0040] A method for recovering valuable metals in a waste residue oil hydrogenation catalyst, comprising the following steps:

[0041] (1) Preparation of a deep eutectic solvent: Choline chloride and benzenesulfonic acid monohydrate were mixed in a molar ratio of 1:3, and stirred at 70°C in a water bath for 30 minutes to obtain a uniform solution, which is a deep eutectic solvent (DES);

[0042] (2) Leaching of waste residue oil hydrogenation catalyst: Grind the waste residue oil hydrogenation catalyst to a particle size of 0.45 mm, dry it at 60° C. to obtain a waste catalyst powder, add 0.1 g of the waste catalyst powder to 5 mL of the low eutectic solvent of step (1), and react in a constant temperature water bath at 60° C. for 6 h to obtain a reaction solution;

[0043] (3) The obtained reaction solution is centrifuged at a centrifugal rate of 8000 rpm for 15 min to obtain a leachate containing valuable metals.

[0044] Determination of the leaching rate of valuable metals: 200 μL of the leachate of Example 2 was diluted 250 times with deionized water. The concentrations of Mo, Ni, and V in the solution were determined by atomic absorption spectrometry to be 21.71 mg / L, 3.26 mg / L, and 10.08 mg / L, respectively. The leaching rate of valuable metals was further calculated based on the metal element content in the waste residue oil hydrogenation catalyst. The leaching rates of Mo, Ni, and V were calculated to be 85.40%, 85.21%, and 75.91%, respectively.

[0045] Example 3

[0046] A method for recovering valuable metals in a waste residue oil hydrogenation catalyst, comprising the following steps:

[0047] (1) Preparation of a deep eutectic solvent: Choline chloride and benzenesulfonic acid monohydrate were mixed in a molar ratio of 1:3, and stirred at 70°C in a water bath for 30 minutes to obtain a uniform solution, which is a deep eutectic solvent (DES);

[0048] (2) Leaching of waste residue oil hydrogenation catalyst: Grind the waste residue oil hydrogenation catalyst to a particle size of 0.45 mm, dry at 60° C. to obtain waste catalyst powder, add 0.15 g of the waste catalyst powder to 5 mL of the low eutectic solvent of step (1), and react in a constant temperature water bath at 60° C. for 5 h to obtain a reaction solution;

[0049] (3) The obtained reaction solution is centrifuged at a centrifugal rate of 8000 rpm for 20 min to obtain a leachate containing valuable metals.

[0050] Determination of the leaching rate of valuable metals: 200 μL of the leachate of Example 3 was diluted 250 times with deionized water. The concentrations of Mo, Ni, and V in the solution were determined by atomic absorption spectrometry to be 35.11 mg / L, 4.83 mg / L, and 16.17 mg / L, respectively. The leaching rate of valuable metals was further calculated based on the metal element content in the waste residue oil hydrogenation catalyst. The leaching rates of Mo, Ni, and V were calculated to be 92.08%, 84.16%, and 81.18%, respectively.

[0051] Example 4

[0052] A method for recovering valuable metals in a waste residue oil hydrogenation catalyst, comprising the following steps:

[0053] (1) Preparation of a deep eutectic solvent: Choline chloride and benzenesulfonic acid monohydrate were mixed in a molar ratio of 1:3, and stirred at 70°C in a water bath for 30 minutes to obtain a uniform solution, which is a deep eutectic solvent (DES);

[0054] (2) Leaching of waste residue oil hydrogenation catalyst: Grind the waste residue oil hydrogenation catalyst to a particle size of 0.45 mm, dry at 60° C. to obtain waste catalyst powder, add 0.15 g of the waste catalyst powder to 5 mL of the low eutectic solvent of step (1), and react in a constant temperature water bath at 90° C. for 5 h to obtain a reaction solution;

[0055] (3) The obtained reaction solution is centrifuged at a centrifugal rate of 8000 rpm for 20 min to obtain a leachate containing valuable metals.

[0056] Determination of the leaching rate of valuable metals: 200 μL of the leachate of Example 4 was diluted 250 times with deionized water. The concentrations of Mo, Ni, and V in the solution were determined by atomic absorption spectrometry to be 25.25 mg / L, 3.74 mg / L, and 12.30 mg / L, respectively. The leaching rate of valuable metals was further calculated based on the metal element content in the waste residue oil hydrogenation catalyst. The leaching rates of Mo, Ni, and V were calculated to be 99.33%, 97.75%, and 92.63%, respectively.

[0057] The main metals Mo and V in the waste residue oil hydrogenation catalyst are leached to form polyacid anions (such as Mo7O24 6- or Mo8O 26 4- 、V6O 19 8- or V 10 O 28 6- ) exists, and the leaching process requires strong acid or oxidizing conditions to destroy its structure. The present invention uses a deep eutectic solvent for leaching, reducing the corrosiveness of strong acids such as sulfuric acid and hydrochloric acid on the tube wall. The Mo leaching efficiency is close to 100%, and the Ni and V leaching efficiency is also greater than 90%.

[0058] Comparative Example 1

[0059] A method for recovering valuable metals in a waste residue oil hydrogenation catalyst is basically the same as that of Example 1, except that the composition of the deep eutectic solvent is different. The composition of the deep eutectic solvent in Comparative Example 1 is: hydrogen acceptor: L-carnitine hydrochloride, hydrogen donor: benzenesulfonic acid monohydrate, the molar ratio of hydrogen acceptor to hydrogen donor is 1:2, and the hydrogen donor is added with 20% water.

[0060] Comparative Example 2

[0061] A method for recovering valuable metals from a waste residue oil hydrogenation catalyst is substantially the same as that of Example 1, except that the composition of the deep eutectic solvent is different. The composition of the deep eutectic solvent in Comparative Example 2 is as follows: a hydrogen acceptor: triethylmethylammonium chloride, a hydrogen donor: benzenesulfonic acid monohydrate, and a molar ratio of the hydrogen acceptor to the hydrogen donor of 1:2.

[0062] Comparative Example 3

[0063] A method for recovering valuable metals in a waste residue oil hydrogenation catalyst is basically the same as that of Example 1, except that the composition of the deep eutectic solvent is different. The composition of the deep eutectic solvent in Comparative Example 3 is: hydrogen acceptor: betaine hydrochloride, hydrogen donor: benzenesulfonic acid monohydrate, the molar ratio of hydrogen acceptor to hydrogen donor is 1:2, and the hydrogen donor is added with 20% water.

[0064] Comparative Example 4

[0065] A method for recovering valuable metals from a waste residue oil hydrogenation catalyst is substantially the same as that of Example 1, except that the composition of the deep eutectic solvent is different. The composition of the deep eutectic solvent in Comparative Example 4 is as follows: a hydrogen acceptor: polyethylene glycol (PEG-400), a hydrogen donor: p-toluenesulfonic acid, and a molar ratio of the hydrogen acceptor to the hydrogen donor of 1:1.

[0066] Comparative Example 5

[0067] A method for recovering valuable metals from a waste residue oil hydrogenation catalyst is substantially the same as that of Example 1, except that the composition of the deep eutectic solvent is different. The composition of the deep eutectic solvent in Comparative Example 5 is as follows: a hydrogen acceptor: choline chloride, a hydrogen donor: p-toluenesulfonic acid, and a molar ratio of the hydrogen acceptor to the hydrogen donor of 2:1.

[0068] Comparative Example 6

[0069] A method for recovering valuable metals from a waste residue oil hydrogenation catalyst is substantially the same as that of Example 1, except that the composition of the deep eutectic solvent is different. The composition of the deep eutectic solvent in Comparative Example 6 is as follows: hydrogen acceptor: choline chloride, hydrogen donors: p-toluenesulfonic acid and ethylene glycol, and the molar ratio of choline chloride to p-toluenesulfonic acid and ethylene glycol is 1:2:1.

[0070] Comparative Example 7

[0071] A method for recovering valuable metals from a waste residue oil hydrogenation catalyst is substantially the same as that of Example 1, except that the composition of the deep eutectic solvent is different. The composition of the deep eutectic solvent in Comparative Example 7 is as follows: hydrogen acceptor: choline chloride, hydrogen donor: ethylene glycol, and a molar ratio of hydrogen acceptor to hydrogen donor of 1:2.

[0072] Comparative Example 8

[0073] A method for recovering valuable metals from a waste residue oil hydrogenation catalyst is substantially the same as that of Example 1, except that the composition of the deep eutectic solvent is different. The composition of the deep eutectic solvent in Comparative Example 8 is as follows: hydrogen acceptor: choline chloride, hydrogen donor: urea, and the molar ratio of hydrogen acceptor to hydrogen donor is 1:2.

[0074] The compositions of the deep eutectic solvents of Example 1 and Comparative Examples 1 to 8 are shown in Table 2.

[0075] Table 2 Composition of deep eutectic solvents of Example 1 and Comparative Examples 1 to 8

[0076] serial number Deep eutectic solvents Hydrogen acceptor (HBA) Hydrogen donor (HBD) Molar ratio (HBA:HBD) Example 1 1 Choline chloride Benzenesulfonic acid monohydrate 1:3 Comparative Example 1 2 L-Carnitine Hydrochloride Benzenesulfonic acid monohydrate 1:2 (add 20wt% water) Comparative Example 2 3 Triethylmethylammonium chloride Benzenesulfonic acid monohydrate 1:2 Comparative Example 3 4 Betaine hydrochloride Benzenesulfonic acid monohydrate 1:2 (add 20wt% water) Comparative Example 4 5 Polyethylene glycol (PEG-400) p-Toluenesulfonic acid 1:1 Comparative Example 5 6 Choline chloride p-Toluenesulfonic acid 2:1 Comparative Example 6 7 Choline chloride p-Toluenesulfonic acid:ethylene glycol 1:2:1 Comparative Example 7 8 Choline chloride Ethylene glycol 1:2 Comparative Example 8 9 Choline chloride urea 1:2

[0077] The leaching rates of Mo, Ni and V in Example 1 and Comparative Examples 1 to 8 were tested, and the results were as follows: Figure 3 As shown by Figure 3 It can be seen that the leaching efficiency of low-melting eutectic-1 for Mo, Ni and V is very high (greater than 90%), and the simultaneous leaching of the three can be achieved, and the types of leached valuable metals are many and the leaching efficiency is high.

[0078] from Figure 3It can be clearly seen that other types of deep eutectic solvents cannot achieve efficient leaching of three metal ions simultaneously, and can only efficiently leach two or even one metal ion of Mo, Ni, and V, and the leaching rate of the corresponding metal is also significantly lower than that of Example 1. In particular, the leaching rate of Ni in the comparative example is relatively low, basically not exceeding 30%. However, the present application not only achieves simultaneous leaching of Mo, Ni, and V, but also achieves a leaching rate of more than 90%, which is much higher than the deep eutectic solvents in each comparative example.

[0079] Comparative Example 9

[0080] A method for recovering valuable metals in a waste residue oil hydrogenation catalyst is substantially the same as that of Example 1, except that the deep eutectic solvent is replaced with choline chloride.

[0081] Comparative Example 10

[0082] A method for recovering valuable metals in a waste residue oil hydrogenation catalyst is substantially the same as that of Example 1, except that the deep eutectic solvent is replaced with benzenesulfonic acid monohydrate.

[0083] The leaching rates of Mo, Ni and V in Example 1 and Comparative Examples 9-10 were tested, and the results were as follows: Figure 4 As shown by Figure 4 As can be seen, choline chloride alone is nearly incapable of leaching metal ions. Under pure benzenesulfonic acid monohydrate conditions, the leaching efficiencies for Mo, Ni, and V were 45.68%, 2.36%, and 55.19%, respectively. However, when the molar ratio of choline chloride to benzenesulfonic acid monohydrate was 1:3, all key metals (Mo, Ni, and V) were almost completely leached. Therefore, the leaching efficiency of deep eutectic solvents is higher than that of single components.

Claims

1. A method for recovering valuable metals from waste residue oil hydrogenation catalyst, characterized in that: The following steps are involved: (1) mixing choline chloride and benzenesulfonic acid monohydrate to obtain a deep eutectic solvent system; (2) grinding and drying the waste residue oil hydrogenation catalyst to obtain a waste catalyst powder; mixing the waste catalyst powder with a low eutectic solvent system and reacting at 50 to 90° C. for 2 to 6 hours, wherein the waste residue oil hydrogenation catalyst is a mixture of composite metal oxides Ni(MoO4) and MoV2O8; (3) The reaction solution obtained in step (2) is centrifuged to obtain a leachate containing Mo ions, Ni ions and V ions.

2. The preparation method according to claim 1, characterized in that Step (3) the leachate contains molybdate ions MoO4 2- , polymolybdate ions, divalent nickel ions Ni 2+ 、Vanadium ion VO2 + , the leachate of polyvanadate ions.

3. The recycling method according to claim 1, wherein: The molar ratio of choline chloride to benzenesulfonic acid monohydrate in step (1) is (1-2):(1-3).

4. The recycling method according to claim 3, characterized in that In step (1), the molar ratio of choline chloride to benzenesulfonic acid monohydrate is 1:

3.

5. The recycling method according to claim 4, characterized in that: In step (2), the ratio of the waste catalyst powder to the low eutectic solvent system is (10-50) g:1 L.

6. The recycling method according to claim 5, characterized in that The ratio of the waste catalyst powder to the low eutectic solvent system in step (2) is 20 g:1 L.

7. The recycling method according to claim 6, characterized in that: In step (2), the reaction temperature is 70° C. and the reaction time is 5 h.

8. The recycling method according to claim 4, characterized in that: In step (2), the waste oil hydrogenation catalyst is ground to a particle size of 0.45 mm.

9. The recycling method according to claim 8, characterized in that: In step (3), the reaction solution is centrifuged at a rate of 8000-9000 rpm for 10-20 min.

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