Method for recovering nickel through alkaline sodium salt roasting of FCC waste catalyst

Abstract

The invention relates to a method for recovering nickel through alkaline sodium salt roasting of an FCC waste catalyst, and relates to the technical field of waste catalyst recycling, the method for recovering nickel through alkaline sodium salt roasting of the FCC waste catalyst comprises the following steps: stirring and mixing an FCC waste catalyst raw material and an alkaline sodium salt agent to obtain sodium salt roasting mixed powder; the sodium salt roasting mixed powder is roasted, and roasted powder is obtained; and adding a sodium hydroxide solution into the roasted powder for heating and leaching treatment, and then filtering and washing to obtain nickel oxide. According to the method for recovering nickel through alkaline sodium salt roasting of the FCC waste catalyst, the ideal nickel enrichment effect can be achieved at the temperature of 900 DEG C in the roasting process, compared with a reduction smelting method, the process temperature is low in energy consumption, and the problems that a traditional high-temperature reduction roasting method is large in energy consumption and high in cost are solved.

Description

Technical Field

[0001] The invention relates to the technical field of waste catalyst recycling, and in particular to a method for recovering nickel by alkaline sodium roasting of FCC waste catalyst. Background Art

[0002] The core of oil refining is the catalyst. The most widely used catalyst in the oil refining industry is FCC (fluid catalytic cracking) catalyst, whose main component is silicon-aluminum composite oxide, and also contains a certain amount of rare earth elements and inorganic elements such as Ni, V, Fe, Ca, Mg and a small amount (1-2%) of coke. With the long-term operation of FCC equipment, the enrichment of heavy metals such as Ni and V leads to the deactivation of the catalyst and the generation of FCC waste catalyst. These waste catalysts have a high content of soluble heavy metals, are difficult to handle, have a high risk of pollution, and pose a serious threat to the human living environment.

[0003] Nickel (Ni) is a heavy metal that is difficult to degrade in nature and is easily enriched in the human body, causing serious health problems. In addition, nickel is also a valuable precious metal. In recent years, it has been widely used as a positive electrode material for lithium batteries. With the rapid development of the new energy industry, the price of nickel has continued to rise, and its value has become increasingly higher. FCC waste catalysts usually contain 0.1wt% to 2.5wt% nickel. If improperly disposed of, it will occupy a large amount of land resources, increase storage costs, and even bring pollution risks to the surrounding environment. In addition, the valuable elements contained therein are not effectively recycled and utilized, which will also cause a great waste of valuable resources. Therefore, the comprehensive recovery of nickel in FCC waste catalysts is of great significance. Studies have shown that the nickel in FCC waste catalysts mainly exists in the form of nickel aluminum spinel NiAl2O4. This structure is very stable and cannot be directly dissolved in acid and alkali. It is very difficult to recycle. At present, the high-temperature reduction roasting method is mainly used to destroy its structure and convert NiAl2O4 into soluble nickel salts to achieve nickel recovery. However, this method has a very high temperature (above 1100°C), high energy consumption, high requirements on the temperature resistance of the equipment, and high cost, which is not conducive to large-scale industrial application. Summary of the invention

[0004] In order to solve the above problems, the present invention provides a method for recovering nickel by alkaline sodium roasting of FCC waste catalyst.

[0005] In a first aspect, the present invention provides a method for recovering nickel by alkaline sodium roasting of FCC waste catalyst, the method comprising the following steps:

[0006] The FCC waste catalyst raw material and the alkaline sodium agent are stirred and mixed to obtain a sodium-treated roasted mixed powder;

[0007] calcining the sodium-calcined mixed powder to obtain a calcined powder;

[0008] A sodium hydroxide solution is added to the calcined powder to perform a heating leaching treatment, followed by filtering and washing to obtain nickel oxide.

[0009] Furthermore, the weight ratio of the FCC waste catalyst raw material to the alkaline sodium agent is 1:(0.2-5).

[0010] Furthermore, the weight ratio of the FCC waste catalyst raw material to the alkaline sodium agent is 1:2.5.

[0011] Furthermore, the alkaline sodium agent includes at least one of sodium carbonate, sodium hydroxide and sodium bicarbonate.

[0012] Furthermore, the working condition parameters of the roasting include: a roasting temperature of 800-950° C. and a roasting time of 30-180 min.

[0013] Furthermore, the working condition parameters of the roasting include: a roasting temperature of 900° C. and a roasting time of 90 minutes.

[0014] Furthermore, the working condition parameters of the heating leaching treatment include: leaching temperature of 25-95° C., and leaching time of 10-60 min.

[0015] Furthermore, the working condition parameters of the heating leaching treatment include: the leaching temperature is 70° C. and the leaching time is 40 minutes.

[0016] Furthermore, when sodium hydroxide solution is added to the calcined powder, the weight percentage concentration of the sodium hydroxide solution is 0.5-40wt%, and the weight of the added sodium hydroxide solution accounts for 0.5-10 times the weight of the calcined powder.

[0017] Furthermore, the washing solvent is a sodium hydroxide solution with a concentration of 1 to 20 wt %.

[0018] The above technical solution provided by the embodiment of the present invention has at least the following advantages compared with the prior art:

[0019] The embodiment of the present invention provides a method for recovering nickel by alkaline sodium roasting of FCC waste catalyst. The method provided by the present invention can achieve a relatively ideal nickel enrichment effect at only 900°C during the roasting process. The process temperature has lower energy consumption than the reduction smelting method, and the aluminum in the FCC waste catalyst is converted into soluble aluminum salt, which can be used to synthesize pseudo-boehmite to achieve the regeneration of catalyst raw materials. The method provided by the present invention has a simple post-processing process, and can achieve efficient separation of nickel from silicon and aluminum main impurities through alkaline leaching and impurity removal. The nickel element is enriched in the alkaline leaching residue in the form of nickel oxide and can be recovered, and the comprehensive recovery rate of nickel reaches more than 90%. BRIEF DESCRIPTION OF THE DRAWINGS

[0020] The accompanying drawings, which are incorporated in and constitute a part of this specification, illustrate embodiments consistent with the invention and, together with the description, serve to explain the principles of the invention.

[0021] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. Obviously, for ordinary technicians in this field, other drawings can be obtained based on these drawings without paying any creative labor.

[0022] Figure 1 A schematic flow chart of a method for recovering nickel from alkaline sodium roasting of FCC waste catalyst provided in an embodiment of the present invention.

[0023] Figure 2 This is a SEM image of the FCC spent catalyst before alkaline sodium calcination in an embodiment of the present invention.

[0024] Figure 3 This is a SEM image of the FCC spent catalyst after alkaline sodium calcination in an embodiment of the present invention. DETAILED DESCRIPTION

[0025] In order to make the purpose, technical solution and advantages of the embodiments of the present invention clearer, the technical solution in the embodiments of the present invention will be clearly and completely described below in conjunction with the drawings in the embodiments of the present invention. Obviously, the described embodiments are part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0026] Unless otherwise specified, various raw materials, reagents, instruments and equipment used in the present invention can be purchased from the market or prepared by existing methods.

[0027] In a first aspect, the present invention provides a method for recovering nickel by alkaline sodium roasting of FCC spent catalyst, such as Figure 1 As shown, the method for recovering nickel by alkaline sodium roasting of FCC waste catalyst comprises the following steps:

[0028] The method for recovering nickel by alkaline sodium roasting of FCC waste catalyst comprises the following steps:

[0029] The FCC waste catalyst raw material and the alkaline sodium agent are stirred and mixed to obtain a sodium-treated roasted mixed powder;

[0030] calcining the sodium-calcined mixed powder to obtain a calcined powder;

[0031] A sodium hydroxide solution is added to the calcined powder to perform a heating leaching treatment, followed by filtering and washing to obtain nickel oxide.

[0032] The embodiment of the present invention provides a method for recovering nickel by alkaline sodium roasting of FCC waste catalyst. The method provided by the present invention can achieve a relatively ideal nickel enrichment effect at only 900°C during the roasting process. The process temperature has lower energy consumption than the reduction smelting method, and the aluminum in the FCC waste catalyst is converted into soluble aluminum salt, which can be used to synthesize pseudo-boehmite to achieve the regeneration of catalyst raw materials. The method provided by the present invention has a simple post-processing process, and can achieve efficient separation of nickel from silicon and aluminum main impurities through alkaline leaching and impurity removal. The nickel element is enriched in the alkaline leaching residue in the form of nickel oxide and can be recovered, and the comprehensive recovery rate of nickel reaches more than 90%.

[0033] In some specific embodiments, the spent FCC catalyst may come from an oil company.

[0034] In some specific embodiments, the weight ratio of the FCC waste catalyst feedstock to the alkaline sodium agent is 1:(0.2-5).

[0035] In some specific embodiments, the weight ratio of the FCC spent catalyst feedstock to the alkaline sodium agent is 1:2.5.

[0036] In some specific embodiments, the alkaline sodium agent includes at least one of sodium carbonate, sodium hydroxide and sodium bicarbonate.

[0037] In some specific embodiments, the working condition parameters of the calcination include: a calcination temperature of 800-950° C. and a calcination time of 30-180 min.

[0038] In some specific embodiments, the working condition parameters of the calcination include: a calcination temperature of 900° C. and a calcination time of 90 min.

[0039] In some specific embodiments, the working condition parameters of the heating leaching treatment include: the leaching temperature is 25-95° C., and the leaching time is 10-60 min.

[0040] In some specific embodiments, the working condition parameters of the heating leaching treatment include: the leaching temperature is 70° C. and the leaching time is 40 min.

[0041] In some specific embodiments, when adding sodium hydroxide solution to the calcined powder, the weight percentage concentration of the sodium hydroxide solution is 0.5-40wt%, and the weight of the added sodium hydroxide solution accounts for 0.5-10 times the weight of the calcined powder.

[0042] In some specific embodiments, the washing solvent is a sodium hydroxide solution with a concentration of 1 to 20 wt %.

[0043] It should be noted that in the method for recovering nickel by alkaline sodium roasting of FCC waste catalyst provided in the embodiment of the present invention, the raw materials involved, unless otherwise specified or limited, can all be commercially available products; at the same time, the process steps and parameters involved can be carried out in accordance with the existing FCC waste catalyst recovery process or using existing equipment in a conventional operating manner.

[0044] The present invention will be further described below in conjunction with specific examples. It should be understood that these examples are intended only to illustrate the present invention and are not intended to limit the scope of the present invention. The experimental methods in the following examples that do not specify specific conditions are usually measured according to national standards. If there is no corresponding national standard, then the conditions recommended by the manufacturer are followed.

[0045] Example 1

[0046] This example provides a method for recovering nickel by alkaline sodium roasting of FCC spent catalyst, comprising the following steps:

[0047] (1) mixing the FCC waste catalyst raw material with sodium hydroxide and sodium carbonate (mixed evenly in a mass ratio of 1:1) and a mixed alkali in a mass ratio of 1:0.2 to obtain an alkaline sodium roasting mixed powder;

[0048] (2) The alkaline sodium calcined mixed powder is calcined at 850° C. for 180 min to obtain a calcined powder, a 40 wt % sodium hydroxide solution is added to the powder, and the mixture is stirred and leached at 25° C. for 10 min, filtered, and a 20 wt % sodium hydroxide solution whose weight is 10 times that of the calcined powder is added to wash and remove soluble substances such as sodium aluminate and sodium silicate to obtain an enriched crude nickel oxide product.

[0049] Example 2

[0050] This example provides a method for recovering nickel by alkaline sodium roasting of FCC waste catalyst, comprising the following steps:

[0051] (1) mixing the FCC waste catalyst raw material with sodium carbonate and sodium bicarbonate (mixed uniformly in a mass ratio of 1:1) and a mixed alkali in a mass ratio of 1:2 to obtain a sodium-roasted mixed powder;

[0052] (2) The alkaline sodium calcined mixed powder is calcined at 950° C. for 80 min to obtain a calcined powder, a 25 wt % sodium hydroxide solution is added to the powder, and the mixture is stirred and leached at 60° C. for 30 min, and then filtered. A 15 wt % sodium hydroxide solution whose weight is 5 times the weight of the calcined powder is added to remove soluble substances such as sodium aluminate and sodium silicate, thereby obtaining an enriched nickel oxide crude product.

[0053] Example 3

[0054] This example provides a method for recovering nickel by alkaline sodium roasting of FCC waste catalyst, comprising the following steps:

[0055] (1) mixing the FCC waste catalyst raw material with sodium carbonate, sodium bicarbonate (mixed evenly in a mass ratio of 1:2.5) and a mixed alkali in a mass ratio of 1:2.5 to obtain a sodium-roasted mixed powder;

[0056] (2) The alkaline sodium calcined mixed powder is calcined at 900° C. for 60 min to obtain a calcined powder, a 15 wt % sodium hydroxide solution is added to the powder, stirred and leached at 70° C. for 40 min, and then filtered, and a 10 wt % sodium hydroxide solution whose weight is 8 times the weight of the calcined powder is added to remove soluble substances such as sodium aluminate and sodium silicate to obtain an enriched nickel oxide crude product.

[0057] Example 4

[0058] This example provides a method for recovering nickel by alkaline sodium roasting of FCC waste catalyst, comprising the following steps:

[0059] (1) mixing the FCC waste catalyst raw material with sodium carbonate and sodium bicarbonate (mixed uniformly in a mass ratio of 1:1) in a mass ratio of 1:4 to obtain a sodium-roasted mixed powder;

[0060] (2) The alkaline sodium calcined mixed powder is calcined at 850° C. for 80 min to obtain a calcined powder, a 5 wt % sodium hydroxide solution is added to the powder, stirred and leached at 95° C. for 10 min, and then filtered, and a 5 wt % sodium hydroxide solution whose weight is twice that of the calcined powder is added to remove soluble substances such as sodium aluminate and sodium silicate to obtain an enriched nickel oxide crude product.

[0061] Example 5

[0062] This example provides a method for recovering nickel by alkaline sodium roasting of FCC waste catalyst, comprising the following steps:

[0063] (1) mixing the FCC waste catalyst raw material with sodium hydroxide and sodium carbonate (mixed evenly in a mass ratio of 1:1) in a mass ratio of 1:3 to obtain a sodium-roasted mixed powder;

[0064] (2) The alkaline sodium-calcined mixed powder is calcined at 800° C. for 120 min to obtain a calcined powder, a 3 wt % sodium hydroxide solution is added to the powder, stirred and leached at 85° C. for 20 min, and then filtered, and a 3 wt % sodium hydroxide solution whose weight is 0.5 times the weight of the calcined powder is added to remove soluble substances such as sodium aluminate and sodium silicate to obtain an enriched nickel oxide crude product.

[0065] Example 6

[0066] This example provides a method for recovering nickel by alkaline sodium roasting of FCC waste catalyst, comprising the following steps:

[0067] (1) mixing the FCC waste catalyst raw material with sodium hydroxide and sodium carbonate (mixed evenly in a mass ratio of 1:1) in a mass ratio of 1:1 to obtain a sodium-roasted mixed powder;

[0068] (2) The alkaline sodium calcined mixed powder is calcined at 880° C. for 100 min to obtain a calcined powder, to which a 0.5 wt % sodium hydroxide solution is added, stirred at 40° C. for leaching for 40 min, and then filtered, and a 1 wt % sodium hydroxide solution whose weight is 3 times the weight of the calcined powder is added to remove soluble substances such as sodium aluminate and sodium silicate to obtain an enriched crude nickel oxide product.

[0069] Comparative Example 1

[0070] This example provides a method for recovering nickel from FCC waste catalyst by alkaline sodium roasting, which differs from Example 2 only in that the mixed alkali of sodium carbonate / sodium bicarbonate is replaced by a single alkali of sodium carbonate in step 1; the remaining steps and parameters are the same.

[0071] Comparative Example 2

[0072] Benli provides a method for recovering nickel from FCC waste catalyst by alkaline sodium calcination, which is different from Example 3 only in that the alkaline sodium calcination mixed powder is calcined at 950°C for 180 minutes; the remaining steps and parameters are the same.

[0073] The leaching solutions and nickel oxide leaching residues prepared in Examples 1-6 and Comparative Examples 1 and 2 were analyzed and tested, and the comprehensive recovery rate of nickel was calculated and compared. The results are shown in Table 1.

[0074] Table 1

[0075] Group Comprehensive recovery rate of nickel (%) Example 1 86.0 Example 2 90.2 Example 3 91.3 Example 4 88.6 Example 5 86.7 Example 6 85.8 Comparative Example 1 75.4 Comparative Example 2 73.3

[0076] It can be seen from Table 1 that, by optimizing the alkaline sodium-forming agent and alkaline sodium-forming roasting process parameters, the comprehensive recovery rate of nickel in Examples 1-6 is increased by more than 10% compared with Comparative Examples 1 and 2.

[0077] In addition, the SEM images of the FCC spent catalyst before and after alkaline sodium calcination in Example 3 are shown in Figures 1 and 2. Figure 2 and Figure 3 As shown in the figure, it can be seen that the FCC waste catalyst is a regular and stable micron-sized spherical structure before calcination. After calcination, the waste catalyst is tightly combined with the alkaline sodium agent and reacts, and the morphology and structure change, which is conducive to the extraction and recovery of nickel inside the FCC waste catalyst.

[0078] In summary, the present invention destroys the regular and stable micron-sized spherical structure of the FCC waste catalyst by mixing the FCC waste catalyst with an alkaline sodium agent and using a lower temperature than the reduction smelting method. The skeleton structure of the waste catalyst is converted into a soluble salt under the action of the alkaline sodium agent, and a simple alkaline leaching and impurity removal process is used to expose the nickel inside the catalyst in the form of nickel oxide so that it can be recovered. The traditional high-temperature reduction smelting method is avoided, and the problems of high temperature, complex process flow, high energy consumption, and high cost are avoided, and the efficient extraction and recovery of nickel is achieved. The comprehensive recovery rate of nickel is more than 90%, and the industrial application prospect is good.

[0079] Various embodiments of the present invention may be presented in the form of a range; it should be understood that the description in the form of a range is only for convenience and brevity and should not be understood as a rigid limitation on the scope of the present invention; therefore, the range description should be considered to have specifically disclosed all possible sub-ranges and single numerical values ​​within the range. For example, the range description from 1 to 6 should be considered to have specifically disclosed sub-ranges, such as from 1 to 3, from 1 to 4, from 1 to 5, from 2 to 4, from 2 to 6, from 3 to 6, etc., as well as single numbers within the range, such as 1, 2, 3, 4, 5 and 6, which apply regardless of the range. In addition, whenever a numerical range is indicated in this article, it is meant to include any quoted numbers (fractions or integers) within the indicated range. In this article, relational terms such as "first" and "second" are used only to distinguish one entity or operation from another entity or operation, and do not necessarily require or imply any such actual relationship or order between these entities or operations.

[0080] The foregoing is merely a specific embodiment of the present invention, which enables those skilled in the art to understand or implement the present invention. Various modifications to these embodiments will be apparent to those skilled in the art, and the general principles defined herein may be implemented in other embodiments without departing from the spirit or scope of the present invention. Therefore, the present invention will not be limited to the embodiments shown herein, but rather to the widest scope consistent with the principles and novel features claimed herein.

Claims

1. A method for recovering nickel from FCC waste catalyst by alkaline sodium roasting. It is characterized in that The method for recovering nickel by alkaline sodium roasting of FCC spent catalyst comprises the following steps: The FCC waste catalyst raw material and the alkaline sodium agent are stirred and mixed to obtain a sodium-treated roasted mixed powder; calcining the sodium-calcined mixed powder to obtain a calcined powder; A sodium hydroxide solution is added to the calcined powder to perform a heating leaching treatment, followed by filtering and washing to obtain nickel oxide.

2. The method for recovering nickel from FCC waste catalyst by alkaline sodium roasting according to claim 1, It is characterized in that The weight ratio of the FCC waste catalyst raw material to the alkaline sodium agent is 1:(0.2-5).

3. The method for recovering nickel from FCC waste catalyst by alkaline sodium roasting according to claim 2, It is characterized in that The weight ratio of the FCC waste catalyst raw material to the alkaline sodium agent is 1:2.

5.

4. The method for recovering nickel from FCC waste catalyst by alkaline sodium roasting according to claim 1, It is characterized in that The alkaline sodium agent includes at least one of sodium carbonate, sodium hydroxide and sodium bicarbonate.

5. The method for recovering nickel from FCC waste catalyst by alkaline sodium roasting according to claim 1, It is characterized in that The working condition parameters of the roasting include: a roasting temperature of 800-950° C. and a roasting time of 30-180 min.

6. The method for recovering nickel from FCC waste catalyst by alkaline sodium roasting according to claim 1, It is characterized in that The working condition parameters of the calcination include: a calcination temperature of 900° C. and a calcination time of 90 minutes.

7. The method for recovering nickel from FCC waste catalyst by alkaline sodium roasting according to claim 1, It is characterized in that The working condition parameters of the heating leaching treatment include: leaching temperature of 25-95° C., and leaching time of 10-60 min.

8. The method for recovering nickel from FCC waste catalyst by alkaline sodium roasting according to claim 1, It is characterized in that The working condition parameters of the heating leaching treatment include: the leaching temperature is 70° C. and the leaching time is 40 minutes.

9. The method for recovering nickel from FCC waste catalyst by alkaline sodium roasting according to claim 1, It is characterized in that When adding sodium hydroxide solution to the calcined powder, the weight percentage concentration of the sodium hydroxide solution is 0.5-40%, and the weight of the added sodium hydroxide solution accounts for 0.5-10 times the weight of the calcined powder.

10. The method for recovering nickel from FCC waste catalyst by alkaline sodium roasting according to claim 1, It is characterized in that The washing solvent is a sodium hydroxide solution with a concentration of 1 to 20 wt %.

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