Method for producing a catalyst for selective hydrogenation of cyclododecatriene and catalyst produced by said method

Abstract

The present invention relates to a method for producing a catalyst for the selective hydrogenation of cyclododecatriene and a catalyst produced by the method. The method for preparing a catalyst for the selective hydrogenation of cyclododecatriene of the present invention includes the steps of (S1) reacting ruthenium chloride with formaldehyde to prepare a ruthenium complex, and (S2) adding triphenylphosphine to the ruthenium complex and then reacting the resulting mixture.

Description

[Technical field]

[0001] The present invention relates to a method for producing a catalyst for the selective hydrogenation of cyclododecatriene and a catalyst produced by the method. [Background technology]

[0002] The synthesis of cyclododecene (CDEN) by selective hydrogenation of cyclododecatriene (CDT) has been frequently described in the literature, and various studies have been carried out to improve the yield of cyclododecene.

[0003] For the selective hydrogenation reaction, a metal-ligand catalyst known as Wilkinson catalyst has been used, that is, a catalyst in which a metal such as rubidium (Ru), rhodium (Rh), cobalt (Co), or nickel (Ni) is combined with a ligand such as triphenylphosphine (TPP) or CO and a halogen element.

[0004] Such catalysts play a key role throughout the entire reaction, such as by not reacting themselves in selective hydrogenation reactions, activating the overall reaction to proceed quickly, or by increasing the yield of products, and therefore various catalyst-related research is being conducted.

[0005] In the US Patent No. 7838705, ruthenium chloride (RuCl3), triphenylphosphine (TPP), formaldehyde, acetic acid, ethanol, etc. are added to a cyclododecatriene hydrogenation reactor, and a ruthenium composite catalyst is synthesized in-situ under hydrogenation reaction conditions and used. This catalyst manufacturing method aims to manufacture a ruthenium composite catalyst that can increase the yield of cyclododecene, but has the disadvantage that hydrochloric acid is generated as a by-product during the catalyst manufacturing process, and reaction residues such as methanol, water, and formaldehyde remain, so that the product separated after the selective hydrogenation reaction contains a large amount of impurities.

[0006] In addition, various solvents are used during the preparation of the catalyst, which makes it difficult to manage and use the solvents, and therefore the entire process is complicated. Summary of the Invention [Problem to be solved by the invention]

[0007] An object of the present invention is to provide a method for producing a catalyst for the selective hydrogenation of cyclododecatriene, which enables the production of a high-purity catalyst through a simple process and gives a high catalyst production yield.

[0008] Another object of the present invention is to provide a catalyst for the selective hydrogenation of cyclododecatriene, which, when used in the selective hydrogenation reaction, can produce cyclododecene in a short period of time with high selectivity and high yield. [Means for solving the problem]

[0009] The method for preparing a catalyst for selective hydrogenation of cyclododecatriene of the present invention includes the steps of (S1) reacting ruthenium chloride with formaldehyde to prepare a ruthenium complex, and (S2) adding triphenylphosphine to the ruthenium complex and reacting the resulting mixture.

[0010] In the method for preparing a catalyst for selective hydrogenation of cyclododecatriene according to one embodiment of the present invention, the step (S1) may be carried out at a temperature of 40°C to 80°C.

[0011] In the method for preparing a catalyst for selective hydrogenation of cyclododecatriene according to one embodiment of the present invention, in the step (S1), the molar ratio of ruthenium chloride:formaldehyde may be 1:20-400.

[0012] In the method for preparing a catalyst for selective hydrogenation of cyclododecatriene according to one embodiment of the present invention, in step (S1), a CO ligand may be formed by the reaction of ruthenium chloride with formaldehyde.

[0013] In the method for preparing a catalyst for selective hydrogenation of cyclododecatriene according to one embodiment of the present invention, the reaction of step (S2) may be carried out at a vaporization temperature of the formaldehyde.

[0014] In the method for preparing a catalyst for selective hydrogenation of cyclododecatriene according to one embodiment of the present invention, in the step (S2), a molar ratio of the ruthenium chloride to the triphenylphosphine added may be 1:1 to 300.

[0015] In the method for preparing a catalyst for selective hydrogenation of cyclododecatriene according to one embodiment of the present invention, in step (S2), a PPh3 ligand may be formed by reacting a ruthenium complex with triphenylphosphine.

[0016] The present invention relates to a catalyst for the selective hydrogenation of cyclododecatriene, which is produced by the above-mentioned method.

[0017] In the catalyst for selective hydrogenation of cyclododecatriene according to one embodiment of the present invention, the catalyst may be added in an amount of 40 ppm to 200 ppm based on ruthenium relative to cyclododecatriene during the selective hydrogenation of cyclododecatriene.

[0018] The catalyst for the selective hydrogenation of cyclododecatriene according to one embodiment of the present invention may be RuH(PPh3)3COCl. Effect of the Invention

[0019] The method for producing a catalyst for the selective hydrogenation of cyclododecatriene according to the present invention can produce a high-purity catalyst in high yield using only relatively simple steps without using a separate solvent.

[0020] The catalyst prepared by the preparation method according to the present invention has excellent catalytic activity, and therefore, when used in the selective hydrogenation of cyclododecatriene, it can shorten the selective hydrogenation time of cyclododecatriene and produce cyclododecene in a high yield. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0021] Unless otherwise defined, technical and scientific terms used in this specification have the meanings that are commonly understood by those having ordinary knowledge in the technical field to which the present invention belongs, and descriptions of known functions and configurations that may obscure the gist of the present invention in the following description and the attached drawings are omitted.

[0022] Also, as used herein, the singular forms "a," "an," and "the" are intended to include the plural forms as well, unless the context indicates otherwise.

[0023] Furthermore, units used in this specification without any special mention are based on weight, and as an example, a unit of % or ratio means % by weight or weight ratio, and % by weight means the weight % that any one component of the entire composition occupies in the composition, unless otherwise defined.

[0024] In addition, the numerical ranges used herein include lower and upper limits and all values ​​within the range, increments logically derived from the form and width of the ranges defined, all values ​​that are doubly limited, and all possible combinations of upper and lower limits of numerical ranges that are limited in different forms. Unless otherwise specified in the specification of the present invention, values ​​outside the numerical ranges that may occur due to experimental error or rounding of values ​​are also included in the defined numerical ranges.

[0025] As used herein, the term "comprising" is an open-ended term having the same meaning as expressions such as "comprising," "containing," "having," or "characterized by," and does not exclude further unrecited elements, materials, or steps.

[0026] Also, as used herein, the term "substantially" means that other elements, materials or steps not listed along with a particular element, material or step may be present in an amount or degree that does not unacceptably affect at least one basic and novel technical idea of ​​the invention.

[0027] The present invention relates to a method for preparing a catalyst for the selective hydrogenation of cyclododecatriene, comprising the steps of (S1) reacting ruthenium chloride with formaldehyde to prepare a ruthenium complex, and (S2) adding triphenylphosphine to the ruthenium complex and then reacting it.

[0028] Conventionally, ruthenium composite catalysts have been synthesized in-situ under hydrogenation conditions by adding ruthenium chloride (RuCl3), triphenylphosphine (TPP), formaldehyde, acetic acid, ethanol, etc. to a cyclododecatriene hydrogenation reactor. This catalyst manufacturing method has the disadvantage that hydrochloric acid is generated as a by-product during the catalyst manufacturing process, and reaction residues such as methanol, water, and formaldehyde remain, so that the product separated after the selective hydrogenation reaction contains a large amount of impurities. In addition, various solvents are used during the catalyst manufacturing process, which makes it difficult to manage and use the solvents, and therefore the overall process is complicated.

[0029] However, the present invention can produce a catalyst for the selective hydrogenation of cyclododecatriene (CDT) from ruthenium chloride, formaldehyde and triphenylphosphine (TPP) in a relatively simple process without using a separate solvent. In addition, since by-products such as HCl are removed during the catalyst production process, a separate separation process is not required to obtain a high-purity catalyst, and the catalyst can be immediately introduced into the selective hydrogenation of cyclododecatriene after production. Furthermore, the present invention can produce a catalyst in high yield during catalyst production, demonstrating excellent process efficiency.

[0030] Furthermore, the catalyst produced by the production method according to the present invention has excellent catalytic activity, and therefore, when used in the selective hydrogenation of cyclododecatriene, it can shorten the selective hydrogenation reaction time of cyclododecatriene and produce cyclododecene in a high yield.

[0031] Specifically, the present invention first performs a step (S1) of reacting ruthenium chloride with formaldehyde to prepare a ruthenium complex. Here, as ruthenium chloride (RuCl3) reacts with formaldehyde (CHO), a CO ligand (carbonyl) can be formed. That is, the ruthenium complex can include a CO ligand and ruthenium.

[0032] The temperature of step (S1) is not limited as long as it is within a range in which ruthenium chloride and formaldehyde react with each other, but it is preferably performed at a temperature of 40° C. to 80° C., and more preferably 50° C. to 60° C. Within this range, ruthenium chloride and formaldehyde can react smoothly in a relatively short time to produce a ruthenium composite.

[0033] In addition, in step (S1), the reaction time can be 10 minutes to 1 hour, specifically 20 minutes to 40 minutes, but is not particularly limited as long as it is a time that allows the reaction of ruthenium chloride and formaldehyde to be completed.

[0034] In step (S1), the molar ratio of ruthenium chloride:formaldehyde may be, but is not limited to, 1:20-400, specifically 1:80-350, and more specifically 1:100-150. However, in the above range, the ruthenium complex produced by the reaction of ruthenium chloride and formaldehyde is dissolved in formaldehyde, and the reaction is smoothly carried out in step (S2) described below. In addition, the ruthenium complex can be formed without consuming ruthenium chloride, which is relatively expensive.

[0035] In step (S1), the ruthenium chloride may be in the form of a dark brown or black powder, and the formaldehyde may be pure formaldehyde or an aqueous formaldehyde solution, etc., and the aqueous formaldehyde solution may have a concentration of 5 wt% to 40 wt%, but is not limited thereto.

[0036] In step (S1), the formation of the CO ligand and the production of the ruthenium complex can be confirmed by visually observing the color change. For example, when ruthenium chloride powder is mixed with a formaldehyde solution, it shows a reddish-brown color before the reaction, but shows a dark green color after the reaction.

[0037] In the present invention, after the step (S1), a catalyst for selective hydrogenation of cyclododecatriene can be prepared by carrying out a step (S2) of adding triphenylphosphine to the ruthenium complex and reacting the resulting mixture. By carrying out the step (S2), a PPh3 ligand can be formed by the reaction of the ruthenium complex with triphenylphosphine. That is, the prepared catalyst can contain the above-mentioned CO ligand and PPh3 ligand.

[0038] Specifically, by carrying out step (S1), molten triphenylphosphine is added to formaldehyde in which a ruthenium complex is dissolved, to obtain a heterogeneous liquid mixture. Here, the molten triphenylphosphine is not specifically limited as long as it is melted at a temperature of 80° C. or higher, which is the melting point, but preferably, a completely molten triphenylphosphine can be used. Next, the ruthenium complex and triphenylphosphine are reacted to produce a catalyst for the selective hydrogenation of cyclododecatriene.

[0039] In step (S2), the reaction may be carried out at the vaporization temperature of formaldehyde. The reaction of the ruthenium complex and triphenylphosphine may be carried out as the formaldehyde is vaporized. The temperature is not limited as long as the formaldehyde is vaporized, but specifically, the reaction may be carried out at a temperature equal to or higher than the melting temperature of triphenylphosphine, preferably 80°C to 200°C, more preferably 100°C to 140°C. In the above range, the remaining formaldehyde, water, methanol, and HCl generated in step (S1), which do not participate in the reaction in step (S1), which do not participate in the reaction, are vaporized, and the ruthenium complex and triphenylphosphine react smoothly in a relatively short time, and the ruthenium complex can be generated in a short time.

[0040] In addition, in step (S2), the reaction time may be any time that allows all of the formaldehyde to evaporate.

[0041] In step (S2), the amount of triphenylphosphine added may be based on the amount of ruthenium chloride added in (S1). Specifically, the molar ratio of ruthenium chloride to triphenylphosphine added may be, but is not limited to, 1:1 to 300, specifically 1:4.5 to 230. However, within the above range, a catalyst having excellent catalytic activity can be produced.

[0042] The present invention also relates to a catalyst produced by the above method, and the catalyst produced by the above method will be described in detail below.

[0043] The catalyst prepared by the above-mentioned method is for selective hydrogenation of cyclododecatriene and can be represented by the chemical formula RuH(PPh3)3COCl. Since such a catalyst has excellent catalytic activity, when it is used in selective hydrogenation of cyclododecatriene, it can shorten the selective hydrogenation time of cyclododecatriene and produce cyclododecene in a high yield.

[0044] Specifically, in the selective hydrogenation of cyclododecatriene, the catalyst of the present invention may be added without limitation as long as the reaction of the reactants can be sufficiently carried out, and may be added in an amount of 40 ppm to 200 ppm, specifically 50 ppm to 150 ppm based on ruthenium, relative to cyclododecatriene. Within this range, the catalyst may have excellent catalytic activity compared to the amount of catalyst added, and cyclododecene (CDEN) may be efficiently produced from cyclododecatriene.

[0045] The selective hydrogenation reaction of cyclododecatriene using the catalyst of the present invention can be carried out under conditions of a temperature of 100 to 200°C and a pressure of 10 to 80 bar, more preferably under conditions of a temperature of 140 to 180°C and a pressure of 20 to 60 bar, and further preferably under conditions of a temperature of 150 to 175°C and a pressure of 20 to 40 bar. However, this is a preferred example for improving the yield of cyclododecene, and it goes without saying that the present invention is not limited thereto.

[0046] The method for preparing a catalyst for selective hydrogenation of cyclododecatriene according to the present invention will be described in more detail with reference to the following examples. However, the following examples are merely a reference for describing the present invention in detail, and the present invention is not limited thereto and may be realized in various forms.

[0047] In addition, unless otherwise defined, all technical and scientific terms have the same meaning as commonly understood by one of ordinary skill in the art to which the present invention belongs. The terms used in the description in this application are merely for the purpose of effectively describing specific embodiments and are not intended to limit the present invention. In addition, the unit of additives not specifically described in the specification may be % by weight.

[0048] Example 1 A reaction solution was prepared by dissolving 31.0 g of RuCl in 119.7 g of formaldehyde (37% formaldehyde aqueous solution), and reacted for 30 minutes at 60° C. After it was confirmed that the reaction solution had changed from reddish brown to dark green, 3.27 g of triphenylphosphine (TPP) that had been completely melted at 100° C. was added and mixed, and the remaining formaldehyde was evaporated at 100° C. to prepare a catalyst.

[0049] Example 2 A catalyst was prepared in the same manner as in Example 1, except that 4.91 g of triphenylphosphine (TPP) was used instead of 3.27 g.

[0050] Example 3 A catalyst was prepared in the same manner as in Example 1, except that 205.7 g of triphenylphosphine (TPP) was used instead of 3.27 g.

[0051] (Experimental Example) In order to evaluate the catalytic performance of the examples, they were introduced as catalysts in the selective hydrogenation reaction of cyclododecatriene, and the reaction time, conversion, and selectivity and yield of cyclododecene were measured.

[0052] The loading conditions for each Example are as shown in Table 1 below. Here, the total amount of TPP used in each Example, including the TPP contained in the catalyst, was fixed at 230 times that of Ru. In the Comparative Example, the loading amount (mol) of CDT was the same as in the Examples, and 30.08 g of RuCl, 9.58 g of formaldehyde (37% formaldehyde aqueous solution), and 20.0 g of TPP were loaded in situ.

[0053] [Table 1]

[0054] After stirring the reaction solution under 6 bar hydrogen, selective hydrogenation was carried out for 2 hours at 180°C and 20 bar, in which the reaction was carried out in a stirred tank reactor equipped with a gas-inducing hollow stirrer. After selective hydrogenation for 1.5 hours, the reaction solution was cooled to below 30°C under nitrogen and then recovered.

[0055] The conversion was calculated according to the following formula 1, the selectivity according to the following formula 2, and the yield according to the following formula 3. The results are shown in Table 2 below.

[0056] [Formula 1] Conversion rate (%) = (CDT0-CDT1-CDDN1) / CDT0 x 100

[0057] In the formula 1, CDT0 is the moles of cyclododecatriene introduced, CDT1 is the moles of cyclododecatriene after the reaction, and CDDN1 is the moles of cyclododecatriene. Here, cyclododecadiene (CDDN) is a product of incomplete hydrogenation in which only one of the three double bonds of cyclododecatriene is hydrogenated and two double bonds remain.

[0058] [Formula 2] Selectivity (%) = CDEN1 / (CDEN1+CDAN1) x 100

[0059] In the above calculation formula 2, CDEN1 is the number of moles of cyclododecene produced, and CDAN1 is the number of moles of cyclododecane, which is a by-product, produced.

[0060] [Formula 3] Yield (%) = Conversion rate x Selectivity

[0061] [Table 2]

[0062] Referring to Table 2, it was confirmed that the catalyst of the present invention can produce cyclododecene with a high conversion rate and selectivity similar to that of the comparative example, and can produce cyclododecene in a high yield in a short reaction time compared to the comparative example.

[0063] The present invention has been described above with reference to specific and limited examples and drawings, but these are provided to facilitate a more general understanding of the present invention. The present invention is not limited to the above examples, and various modifications and variations are possible from such descriptions by those having ordinary knowledge in the field to which the present invention pertains.

[0064] Therefore, the concept of the present invention should not be limited to the above-described embodiments, and it can be said that not only the scope of the claims described below, but also all modifications that are equivalent or equivalent to the scope of the claims fall within the scope of the concept of the present invention.

Claims

1. (S1) reacting ruthenium chloride with formaldehyde to produce a ruthenium composite dissolved in formaldehyde; (S2) adding triphenylphosphine to the ruthenium complex and then reacting the same; In the step (S1), a CO ligand is formed by the reaction of ruthenium chloride with formaldehyde; The reaction of the step (S2) is carried out at a vaporization temperature of the formaldehyde.

2. The method for preparing a catalyst for the selective hydrogenation of cyclododecatriene according to claim 1, wherein the step (S1) is carried out at a temperature of 40°C to 80°C.

3. 2. The method for producing a catalyst for selective hydrogenation of cyclododecatriene according to claim 1, wherein in the step (S1), the molar ratio of ruthenium chloride:formaldehyde is 1:20-400.

4. 2. The method for producing a catalyst for selective hydrogenation of cyclododecatriene according to claim 1, wherein in the step (S2), a molar ratio of the ruthenium chloride to the triphenylphosphine is 1:1 to 300.

5. In the step (S2), PPh is obtained by reacting a ruthenium complex with triphenylphosphine. ３ The method for producing a catalyst for the selective hydrogenation of cyclododecatriene according to claim 1, wherein a ligand is formed.

6. The catalyst is RuH(PPh ３ ) ３ A method for producing the catalyst for the selective hydrogenation of cyclododecatriene according to claim 1, wherein the catalyst is COCl.

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