Method for manufacturing a catalyst and the catalyst produced thereby

Abstract

This invention provides a catalyst that can significantly reduce impurities containing Na, and a method for producing the same. [Solution] The present invention discloses a method for producing a catalyst. The method includes the steps of: producing a first slurry by deposition-precipitation of an activated metal precursor onto a support; filtering the first slurry to obtain a first catalyst cake; repulping the catalyst cake to produce a second slurry; filtering the second slurry to obtain a second catalyst cake having an electrical conductivity of 300 μS or less of the filtered solution; and drying and calcining the catalyst cake.

Description

Technical Field

[0001] The present invention relates to a method for producing a catalyst and a catalyst produced thereby. More specifically, the present invention relates to a method for producing a hydrogenation catalyst produced by the deposition-precipitation method, which can minimize the content of impurities containing Na and improve the activity of the catalyst, and a catalyst produced thereby.

Background Art

[0002] Hydrogenation catalysts can be produced by various methods such as the coprecipitation method and the deposition-precipitation method. Among them, the deposition-precipitation method (DP method) has the advantage that since a carrier with adjusted particle size can be used, it is easy to produce a catalyst having particle size, size distribution, surface area, pore structure, etc. suitable for the reaction.

[0003] However, when producing a catalyst by the DP method, precipitants such as Na2CO3, NaOH, and NaHCO3 are required. If Na is present in the catalyst, the catalyst activity is significantly reduced. Therefore, it is necessary to sufficiently remove Na, which is an impurity, in the filtration / washing process after precipitation.

[0004] Therefore, a method of repeatedly performing filtration and washing to remove Na impurities has been proposed, but there is a limit to reducing the Na content to less than 200 ppm. When an impurity, Na, remains in the finished catalyst in this way, it leads to a decrease in hydrogenation activity and acts as a problem of the DP method.

[0005] Therefore, there is a need to develop a method for producing a catalyst that has the advantages of the DP method and can significantly reduce the Na content and improve the catalyst activity.

[0006] As a related prior art, there is KR10-2703588.

Prior Art Documents

[0007] [Patent Document 1] No. KR10-2703588 [Overview of the project] [Problems that the invention aims to solve]

[0008] The object of the present invention is to provide a catalyst that can significantly reduce impurities containing Na, and a method for producing the same.

[0009] Another object of the present invention is to provide a catalyst and a method for producing the same that have excellent catalytic activity, while also possessing the advantages of the DP method, such as high active metal content and controllable particle size.

[0010] Another object of the present invention is to provide a method for reducing the Na content of a hydrogenation catalyst produced by deposition-precipitation.

[0011] All of the aforementioned and other objectives of the present invention can be achieved by the present invention as described below. [Means for solving the problem]

[0012] 1. One aspect of the present invention relates to a method for producing a catalyst. The method includes the steps of: producing a first slurry by deposition-precipitation of an activated metal precursor onto a support; filtering the first slurry to obtain a first catalyst cake; repulping the catalyst cake to produce a second slurry; filtering the second slurry to obtain a second catalyst cake having an electrical conductivity of 300 μS or less of the filtered solution; and drying and calcining the catalyst cake.

[0013] 2. In the specific example of paragraph 1 above, the method can be repeated two or more times such that the electrical conductivity of the filtered solution is 300 μS or less.

[0014] 3. In the specific examples of 1 to 2 above, the repulping can be carried out at 60°C to 80°C.

[0015] 4. In the specific examples of 1 to 3 above, the first slurry can have a pH of 7 to 9.

[0016] 5. In the specific examples of 1 to 4 above, when the drying temperature is T1 and the firing temperature is T2, the following formula 1 can be satisfied:

[0017] [Formula 1] T1 × 3.1 ≤ T2 ≤ T1 × 3.9

[0018] (In formula 1, T1 is the drying temperature (°C) and T2 is the firing temperature (°C)).

[0019] 6. In the specific examples of 1 to 5 above, after firing, a reduction step can further be included.

[0020] 7. In the specific examples of 1 to 6 above, after reduction, an immobilization step can further be included.

[0021] [[ID=ID=33]]8. In the specific examples of 1 to 7 above, the immobilization can be carried out with a nitrogen mixed gas containing 0.1% to 20% by volume of oxygen.

[0022] 9. In the specific examples of 1 to 8 above, the active metal precursor can include a nickel compound.

[0023] 10. In the specific examples of 1 to 9 above, the active metal precursor can further include a copper compound, a cerium compound, or a combination thereof.

[0024] 11. In the specific examples of 1 to 10 above, the carrier can include silica powder.

[0025] 12. In the specific examples of 1 to 11 above, the silica powder has a specific surface area of 200 m / g~400m 2 / g, it can have a pore size of 10 nm to 30 nm.

[0026] 13. Another aspect of the present invention relates to a catalyst produced by the above specific examples 1 to 12. The catalyst can have a Na content of less than 200 ppm.

[0027] 14. In the specific example of 13 above, the catalyst can have a Na content of less than 50 ppm.

[0028] 15. In the specific examples of 13 to 14 above, the catalyst can be used for hydrogenation reactions.

[0029] 16. Another aspect of the present invention relates to a method for reducing the Na content of a hydrogenation catalyst produced by the deposition-precipitation method. The method includes filtering the obtained first slurry after deposition-precipitation to obtain a catalyst cake, repulping the catalyst cake to produce a second slurry; and repeating repulping and filtration until the electrical conductivity of the filtrate of the second slurry becomes 300 μS or less.

[0030] 17. In the specific example of 16 above, the repulping can be performed at 60 °C to 80 °C.

Advantages of the Invention

[0031] The present invention can significantly reduce impurities containing Na, enables high content of active metal and particle size control, which are the advantages of the DP method, and has the effect of providing a catalyst with excellent catalytic activity and a method for producing the same. <00001b>

Brief Description of the Drawings

[0032] [Figure 1] It is a flowchart of a method for producing a catalyst according to one specific example of the present invention.

Embodiments for Carrying Out the Invention

[0033] The present invention will be described in more detail below. When "includes," "has," "becomes," etc., as used herein, other parts may be added unless "only" is used. When a component is expressed singularly, it may include multiple components unless otherwise explicitly stated.

[0034] In interpreting the constituent elements, even without further explicit mention, they shall be interpreted as including a margin of error.

[0035] The following describes in detail the method for producing the catalyst according to the present invention.

[0036] Catalyst manufacturing method

[0037] One aspect of the present invention relates to a method for producing a catalyst. The method includes the steps of: producing a first slurry by deposition-precipitation of an activated metal precursor on a support; filtering the first slurry to obtain a first catalyst cake; repulping the catalyst cake to produce a second slurry; filtering the second slurry to obtain a second catalyst cake having an electrical conductivity of 300 μS or less of the filtered solution; and drying and calcining the catalyst cake.

[0038] Figure 1 is a flowchart of a method for producing a catalyst according to one specific example of the present invention.

[0039] A first slurry can be produced by precipitation-precipitation of an active metal precursor onto a support. In this deposition-precipitation method, a metal precursor salt solution and a pH adjusting agent react in a support dispersion to form a precipitate, which is then adsorbed and solidified on the surface of the support. The deposition-precipitation method (DP method) is incomparably superior to metal catalysts produced by existing coprecipitation and impregnation methods in terms of catalyst uniformity. Therefore, when producing a catalyst by the DP method using a support with a uniform particle size distribution, it has the advantage of being easy to select and optimize a support with particle size, size distribution, surface area, porosity structure, etc., that are suitable for the reaction.

[0040] In one specific example, the active metal precursor may include a nickel compound. The nickel compound may include, but is not limited to, nickel sulfate, nickel nitrate, nickel chloride, etc. In another specific example, the nickel compound may further include a copper compound, a cerium compound, or a combination thereof. Examples of such compounds include copper nitrate, copper sulfate, copper chloride, cerium nitrate, cerium sulfate, and cerium chloride.

[0041] In a specific example, the carrier may include silica powder. The silica powder has a specific surface area of ​​200 m². 2 / g~400m 2 The silica powder can have pore sizes ranging from 10 nm to 30 nm per gram. Within this range, activity and catalyst lifetime can be improved, and an optimal effect of improving the efficiency of the product-catalyst separation process can be achieved. The silica powder may have an average particle size D10 of 2 μm or more, a D50 of 5 μm to 7 μm, and a D90 of 15 μm or less. In this way, excellent activity and catalyst lifetime can be obtained by using a silica support with a uniform particle size distribution.

[0042] In specific examples, 5 to 20 parts by weight of the carrier can be applied to 100 parts by weight of the active metal precursor. Because the DP method is applied in this invention, the content of the active metal can be increased. Therefore, excellent catalytic activity and dispersibility can be ensured. Furthermore, sulfur or other substances can be used as accelerators as needed. In specific examples, the accelerator can be used in amounts of 0.1 to 3.0 parts by weight per 100 parts by weight of the active substance.

[0043] The activated metal precursor and the carrier are mixed with water and stirred, after which a precipitating agent is added. The precipitating agent may be, but is not limited to, sodium carbonate, sodium hydroxide, sodium bicarbonate, sodium sulfide, or sodium phosphate. These can be used individually or in combination of two or more.

[0044] In one specific example, the mixture of the active metal precursor and the support can be heated to 60°C to 90°C before adding the precipitating agent.

[0045] The first slurry formed after the aforementioned precipitation is complete may have a pH of 7 to 9, and in specific cases, a pH of 8 to 8.9.

[0046] In a specific example, the first slurry can undergo an aging process before filtration. This aging process can be carried out for 30 minutes to 2 hours. Within this range, more uniform particle formation becomes possible.

[0047] The first slurry can be used to obtain a first catalyst cake through a filtration process. This filtration can preferably be performed using a vacuum filtration apparatus.

[0048] The first catalyst cake is used to produce a second slurry through a repulping process.

[0049] In a specific example, the repulping involves redispersing the first catalyst cake in a solvent and stirring. In this way, by pulverizing and redispersing the catalyst cake, impurities present in the cake dissolve into the solvent, enabling the filtration solution to achieve an electrical conductivity of 300 μS or less. The solvent can be water, preferably distilled water. In a specific example, the stirring can be performed at 300 rpm to 1,000 rpm. Within this range, uniform washing can be completed, and the Na content of the final manufactured catalyst can be reduced to less than 200 ppm.

[0050] In one specific example, the repulping can be carried out at 60°C to 80°C. Within this range, the Na content of the catalyst can be achieved to less than 100 ppm, preferably less than 50 ppm.

[0051] A second slurry is formed through the repulping process, and the second slurry undergoes another filtration process. In a specific example, the filtration and repulping steps can be repeated.

[0052] In a specific example, as shown in Figure 1, the second slurry is filtered to produce a second catalyst cake, and at this time, the electrical conductivity of the filtered solution is measured to confirm that it is 300 μS or less. If the electrical conductivity exceeds 300 μS, the repulping and filtering process is repeated. Once the electrical conductivity of the filtered solution reaches 300 μS or less, it undergoes a drying and calcination process. At this time, the critical (threshold) electrical conductivity is preferably 300 μS or less, and if it exceeds 300 μS, it becomes difficult to achieve the Na content in the final catalyst, which is the target of this invention, to be less than 200 ppm.

[0053] When the electrical conductivity of the filtered solution reaches 300 μS or less, it undergoes a drying process. This drying can be carried out in a drying oven, for example, at 100°C to 150°C. Once the drying is complete, it undergoes a firing process. This firing can be carried out at 310°C to 395°C. In a specific example, when the drying temperature is T1 and the firing temperature is T2, the following equation 1 can be satisfied:

[0054] [Formula 1] T1 × 3.1 ≤ T2 ≤ T1 × 3.9

[0055] (In the above formula 1, T1 is the drying temperature (°C) and T2 is the firing temperature (°C).)

[0056] Within the aforementioned range, a decrease in catalytic activity can be prevented, and a superior lifespan can be achieved.

[0057] After the calcination is complete, a reduction step may be further included. This reduction can be carried out in a hydrogen atmosphere at 350°C to 450°C. Excellent catalytic activity is observed within this range.

[0058] After the reduction is complete, the procedure may further include a deactivation step. This deactivation can be performed with a nitrogen gas mixture containing 0.1% to 20% by volume of oxygen.

[0059] The catalyst produced by the above method has a Na content of less than 200 ppm, specifically less than 100 ppm, preferably less than 50 ppm, and more preferably 1 ppm to 45 ppm.

[0060] In a specific example, the particle size distribution of the catalyst may have an average particle diameter of 2 μm or more for D10, 5 μm to 7 μm for D50, and 15 μm or less for D90.

[0061] Furthermore, the mesopore size is 4.5 nm or larger, and the BET specific surface area is 200 m². 2 At concentrations of 0.25 cm³ / g or higher, the cumulative adsorption volume of BJH may exceed 0.25 cm³ / g.

[0062] Furthermore, the nickel content of the catalyst may be 50% by weight or more of the total catalyst weight, and in specific cases, it may be 60% to 80% by weight.

[0063] The catalyst can have both a low Na content and a high Ni content, and because the catalyst particle size is uniform, it can be preferably applied to hydrogenation reactions.

[0064] The present invention will be described more specifically below through examples and comparative examples, but such examples are for illustrative purposes only and should not be construed as limiting the present invention.

[0065] Examples

[0066] Example 1

[0067] 12 g of amorphous silica powder, 168 g of nickel sulfate, 2 g of copper sulfate, and 600 ml of distilled water were placed in a precipitation vessel, stirred, and heated to 80°C. 500 ml of a precipitant solution containing 87 g of sodium carbonate was injected entirely into the raw material solution reactor using a syringe pump over a period of 1 hour. After precipitation was complete, the slurry pH was 8.5, and it was aged for 1 hour to allow for uniform particle formation. The slurry containing the catalyst cake was filtered using a vacuum filter. The filtered catalyst cake was redispersed in 2 L of distilled water and repulped by stirring at room temperature for 30 minutes. The slurry containing the repulped catalyst cake was filtered using a vacuum filter. The filtration / repulping process was repeated three times to thoroughly wash the catalyst cake until the electrical conductivity of the catalyst cake filtration solution reached 100 μS. The catalyst cake was then dried in a drying oven at 105°C for at least 12 hours. After drying, the sample was filtered to a specific particle size using a standard, divided into smaller portions, and then calcined at 350°C in an air atmosphere. These portions were then divided again and reduced at 400°C in a hydrogen atmosphere. After reduction, the nickel-based catalyst was produced by immobilization using a nitrogen mixed gas containing 1 vol.% oxygen.

[0068] Example 2

[0069] The procedure was carried out in the same manner as in Example 1, except that the repulping and filtration process was interrupted when the electrical conductivity of the catalyst cake filtration solution reached the range of 200 μS to 300 μS, and the subsequent steps were performed.

[0070] Comparative Example 1

[0071] After precipitation was complete, the process of washing the catalyst cake was omitted, and the catalyst was manufactured by drying and calcining in the same manner as in Example 1.

[0072] Comparative Example 2

[0073] The procedure was the same as in Example 1, except that the filtration / precipitation process was performed only once to adequately wash the catalyst cake.

[0074] Comparative Example 3

[0075] The procedure was carried out in the same manner as in Example 1, except that the repulping and filtration process was interrupted when the electrical conductivity of the catalyst cake filtration solution reached 3,000 μS to 4,000 μS, and the subsequent steps were performed.

[0076] The physical properties of the manufactured catalyst were evaluated using the following method, and the results are shown in Table 1.

[0077] (1)ICP-AES analysis

[0078] For ICP-AES analysis, the catalyst was completely dissolved using nitric acid and hydrofluoric acid, and this solution was diluted 500-fold before ICP-AES analysis was performed.

[0079] (2) Experiments on catalyst activity

[0080] The hydrogenation reaction was carried out using a 300 mL autoclave equipped with a hollow shaft stirrer and having a stirring speed of 1,200 rpm. 75 g of a solution was prepared by dissolving non-hydrogenated petroleum resin in Esol D15 at 30% by weight. Then, the solution was hydrogenated at 230°C and 80 bar with the addition of a catalyst prepared at 0.5% of the petroleum resin's mass for 1 hour. After the reaction, the petroleum resin was degassed, and the aromatics, olefin, and alphatic content were analyzed by 1H-NMR. The catalyst activity was calculated according to the degree of saturation of the unsaturated bonds in the aromatics and olefins.

[0081] [Table 1]

[0082] As shown in Table 1 above, the catalyst produced by the method of the present invention achieves a Na content of less than 200 ppm and exhibits excellent catalytic activity. On the other hand, in Comparative Examples 1 to 3, where the electrical conductivity of the final filtrate exceeded the range of the present invention, it can be confirmed that the Na content in the catalyst increased significantly and the catalytic activity also decreased.

[0083] Simple modifications and alterations of the present invention can be readily carried out by a person with ordinary skill in the art, and all such modifications and alterations can be considered to fall within the scope of the present invention.

Claims

1. A step of producing a first slurry by precipitation-precipitation of an active metal precursor on a support; The first step of filtering the first slurry to obtain the first catalyst cake; A step of repulping the catalyst cake to produce a second slurry; The steps include: filtering the second slurry to obtain a second catalyst cake in which the electrical conductivity of the filtered solution is 300 μS or less; and A step of drying and baking the catalyst cake; A method for producing a catalyst, including the following:

2. The method for producing a catalyst according to claim 1, wherein the repulping and filtration are repeated two or more times so that the electrical conductivity of the filtered solution is 300 μS or less.

3. The method for producing a catalyst according to claim 1, wherein the repulping is carried out at 60°C to 80°C.

4. The method for producing a catalyst according to claim 1, wherein the first slurry has a pH of 7 to 9.

5. A method for producing a catalyst according to claim 1, wherein when the drying temperature is T1 and the firing temperature is T2, the following formula 1 is satisfied: [Formula 1] T1 × 3.1 ≤ T2 ≤ T1 × 3.9 (In the above formula 1, T1 is the drying temperature (°C) and T2 is the firing temperature (°C).)

6. The method for producing a catalyst according to claim 1, further comprising the step of reduction after the calcination.

7. The method for producing a catalyst according to claim 6, further comprising the step of immobilizing the catalyst after the reduction.

8. The method for producing a catalyst according to claim 7, wherein the immobilization is performed using a nitrogen mixed gas containing 0.1 volume% to 20 volume% oxygen.

9. The method for producing a catalyst according to claim 1, wherein the activated metal precursor contains a nickel compound.

10. The method for producing a catalyst according to claim 9, wherein the active metal precursor further comprises a copper compound, a cerium compound, or a combination thereof.

11. The method for producing a catalyst according to claim 1, wherein the carrier contains silica powder.

12. The silica powder has a specific surface area of ​​200 m². ２ / g to 400m ２ A method for producing a catalyst according to claim 11, wherein the catalyst has a pore size of 10 nm to 30 nm at a concentration of / g.

13. A catalyst produced by the method according to any one of claims 1 to 12, having a Na content of less than 200 ppm.

14. The catalyst according to claim 13, wherein the catalyst has a Na content of less than 50 ppm.

15. The catalyst according to claim 13, wherein the catalyst is used in a hydrogenation reaction.

16. A method for reducing the Na content of a hydrogenation catalyst produced by the deposition-precipitation method, wherein the method is After precipitation and deposition, the obtained first slurry is filtered to obtain a catalyst cake. The catalyst cake is repulped to produce a second slurry; and A method comprising the step of repeating repulping and filtration until the electrical conductivity of the filtered solution of the second slurry is 300 μS or less.

17. The method according to claim 16, wherein the repulping is carried out at 60°C to 80°C.

Images