Preparation method of octadiene monomethyl ether and used catalyst
By introducing fluorine atoms outside the catalyst ligand ring, the electron-withdrawing and steric hindrance effects are enhanced, solving the problem of low activity and selectivity in the catalytic synthesis of octadiene monomethyl ether, and realizing the efficient preparation of octadiene monomethyl ether.
Patent Information
- Application Number
- CN202411084420.2
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2024-08-08
- Publication Date
- 2026-02-10
AI Technical Summary
In existing technologies, the catalysts for the catalytic synthesis of octadiene monomethyl ether have low activity and selectivity, resulting in low production efficiency of 1-octene, especially in the first step of the telomerization reaction.
A catalyst was prepared using palladium-containing compounds and ligands with specific structures. Fluorine atoms were introduced outside the ligand ring to enhance electron-withdrawing ability and steric hindrance effect, and the reaction conditions were mild.
Under mild reaction conditions, butadiene conversion reached 100% and octadiene monomethyl ether selectivity reached 94%, significantly improving catalytic activity and selectivity.
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Abstract
Description
TECHNICAL FIELD
[0001] The present application relates to the field of 1-octene production, and particularly relates to a preparation method of octadiene monomethyl ether (1-MOD) and a catalyst for catalytically synthesizing octadiene monomethyl ether. BACKGROUND
[0002] 1-octene is an important comonomer and organic raw material, mainly used for producing high-end polyethylene, POE elastomer, PAO base oil, plasticizer, surfactant and other high value-added products, and widely applied in plastic, rubber and textile fields, and thus has a high demand. However, 1-octene is difficult to produce, has high technical barriers and is highly monopolized in the industry.
[0003] 1-octene production technologies mainly include wax cracking method, ethylene oligomerization method, Fischer-Tropsch synthesis method and butadiene telomerization method. The wax cracking method was the first to realize industrial production, but it has been eliminated because of its complex product components, purification difficulties and lack of competitiveness in economy and product quality. The ethylene oligomerization method has high product purity and good atom economy, but has problems such as easy generation of oligomers in the reaction and low product selectivity. The Fischer-Tropsch synthesis method contains a certain amount of high-carbon alpha-olefins in the product, but the olefins and alkanes have similar boiling points and are difficult to separate, so the purity of 1-octene is low. Therefore, in 1992, DOW Company developed a new route for producing 1-octene by cracking methyl octyl ether, which improved the preparation process of 1-octene. The reaction structure is shown below. First, two butadiene molecules and one methanol molecule undergo telomerization to form 1-MOD; then 1-MOD forms methyl octyl ether, and finally methyl octyl ether is cracked to obtain the target product 1-octene. According to the existing technical data, the second and third steps have high efficiency and high selectivity, and the related products can almost achieve quantitative conversion. Therefore, the efficiency of the whole process mainly depends on the first step, i.e. the telomerization of 1,3-butadiene and methanol.
[0004]
[0005] EP0561779B1 discloses a method for producing 1-octene, comprising the following steps: (i) reacting 1,3-butadiene with a compound containing active hydrogen atoms and having the formula R-H in the presence of a telomerization catalyst to form 1-substituted-2,7-octadiene, wherein R represents the residue of a primary aliphatic alcohol or an aromatic hydroxyl compound; (ii) hydrogenating the 1-substituted-2,7-octadiene formed in step (i) in the presence of a hydrogenation catalyst to form 1-substituted octane; and (iii) decomposing the 1-substituted octane formed in step (ii) in the presence of a suitable catalyst to form 1-octene. The n / i ratio of the 1-octene obtained by this method is low.
[0006] CN115007217A discloses a heterogeneous solid polymer palladium catalyst, a preparation method thereof, and a method for preparing 2,7-octadiene methyl ether by catalyzing butadiene telomerization. The polymer palladium catalyst comprises metal palladium as an active component and a carrier polymer as a carrier, wherein the carrier polymer is polymerized from styrene and vinyl-functionalized triphenylphosphine. The catalyst has good stability and can be recycled, and the conversion rate is up to 90%. However, the reaction activity of the catalyst is slightly low.
[0007] Therefore, further research is still needed in the art on catalysts for catalyzing the synthesis of octadiene monomethyl ether and methods for preparing octadiene monomethyl ether. SUMMARY
[0008] The main purpose of the present application is to provide a method for preparing octadiene monomethyl ether and a catalyst for catalyzing the synthesis of octadiene monomethyl ether. The catalyst of the present application has high catalytic activity and is used for catalyzing the synthesis of octadiene monomethyl ether, which has high conversion rate and selectivity.
[0009] In order to achieve the above purpose, the present application provides a catalyst for catalyzing the synthesis of octadiene monomethyl ether, comprising a palladium-containing compound and a ligand, wherein the ligand has the following formula I structure:
[0010]
[0011] wherein the substituents R1, R2, R3, R4, R5, R6, R7, R8, R9, R 10 , R 11 , R 12 , R 13 , R 14 , R 15 are independently selected from fluorine, methyl and hydrogen, and at least one substituent is fluorine.
[0012] The catalyst for catalyzing the synthesis of octadiene monomethyl ether according to the present application, wherein the molar ratio of the palladium-containing compound to the ligand is 0.5-5:1-10; the palladium-containing compound is at least one of palladium acetylacetonate, palladium acetate and palladium chloride.
[0013] In order to achieve the above purpose, the present application further provides a method for preparing octadiene monomethyl ether, comprising the following steps:
[0014] Mixing butadiene, methanol, a solvent and the catalyst for catalyzing the synthesis of octadiene monomethyl ether according to claim 1 or 2, reacting to obtain octadiene monomethyl ether.
[0015] The method for preparing octadiene monomethyl ether according to the present application, wherein the solvent is at least one of methanol, hexane and cyclohexane.
[0016] The preparation method of octadiene monomethyl ether, wherein the molar ratio of the palladium-containing compound to butadiene is 0.005%-0.05%.
[0017] The preparation method of octadiene monomethyl ether, wherein the molar ratio of the ligand to butadiene is 0.01%-0.1%.
[0018] The preparation method of octadiene monomethyl ether, wherein a promoter is further added in the reaction mixture, the promoter is an alkaline substance, and the molar ratio of the promoter to butadiene is 0.1%-0.7%.
[0019] The preparation method of octadiene monomethyl ether, wherein the promoter is at least one of sodium methoxide, potassium methoxide, sodium carbonate, potassium carbonate, sodium formate and sodium hydroxide.
[0020] The preparation method of octadiene monomethyl ether, wherein the reaction temperature is 25-110°C, and the reaction time is 0.5-6h.
[0021] The preparation method of octadiene monomethyl ether, wherein the molar ratio of the methanol to butadiene is 1-3:3-1.
[0022] The present application has the following advantages:
[0023] The present application introduces F atoms on the substituents outside the ligand ring, strengthens the electron-withdrawing ability of the ligand, improves the catalytic activity of the catalyst, and reduces the requirements for the reaction conditions. In addition, by introducing F atoms, the steric hindrance effect of the ligand is strengthened, and the selectivity of the catalyst can be improved.
[0024] The catalyst of the present application is used for catalytically synthesizing octadiene monomethyl ether, and under mild reaction conditions, the butadiene conversion rate can reach 100%, and the 1-MOD selectivity can reach 94%. BRIEF DESCRIPTION OF DRAWINGS
[0025] In order to more clearly illustrate the specific embodiments of the present application or the technical solutions in the prior art, the drawings needed in the specific embodiments or prior art description will be briefly introduced below. Obviously, the drawings in the following description are some embodiments of the present application, and those skilled in the art can also obtain other drawings according to these drawings without creative labor.
[0026] Figure 1 The gas chromatogram of the reaction mixture after Example 1 of the present application. DETAILED DESCRIPTION
[0027] The technical solutions of the present application are described in detail below. The following embodiments are implemented on the premise of the technical solutions of the present application, and detailed implementation processes are given. However, the protection scope of the present application is not limited to the following embodiments. The structures or experimental methods not specified in the following embodiments are usually implemented according to conventional conditions.
[0028] The present application provides a catalyst for catalytically synthesizing octadiene monomethyl ether, which comprises a palladium-containing compound and a ligand having the following formula I:
[0029]
[0030] wherein the substituents R1, R2, R3, R4, R5, R6, R7, R8, R9, R 10 , R 11 , R 12 , R 13 , R 14 , R 15 are independently selected from fluorine, methyl and hydrogen, and at least one substituent is fluorine.
[0031] The present application strengthens the electron-withdrawing ability of the ligand by introducing F atoms to the substituents outside the ring of the ligand, thereby improving the catalytic activity of the catalyst and reducing the requirements for the reaction conditions. In addition, the introduction of F atoms strengthens the steric hindrance effect of the ligand, thereby improving the selectivity of the catalyst.
[0032] The present application does not particularly limit the number of fluorine substituents in the ligand, which may be, for example, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14 or 15. In an embodiment, the substituents at specific positions of the ligand of the present application are fluorine, which can further strengthen the electron-withdrawing ability of the ligand and improve the catalytic activity of the catalyst. For example, the substituents on the three benzene rings connected to phosphorus are the same. Specifically, for example, R5, R 10 , R 15 are fluorine, and the rest are hydrogen, i.e. tris(2-fluorophenyl) phosphine, as shown below L1; more for example, R4, R9, R 12 are fluorine, and the rest are hydrogen, i.e. tris(3-fluorophenyl) phosphine, as shown below L2; still more for example, R1-R 15 are all fluorine, i.e. all substituents are fluorine, i.e. tris(pentafluorophenyl) phosphine, as shown below L3.
[0033]
[0034] The present application does not particularly limit the source of the ligand, which may be a commercially available product or prepared according to the prior art.
[0035] The palladium compound in the present application plays a main catalytic role. In one embodiment, the palladium-containing compound is at least one of palladium acetylacetonate, palladium acetate, and palladium chloride, preferably palladium chloride.
[0036] In one embodiment, the molar ratio of the palladium-containing compound to the ligand is 0.5-5:1-10.
[0037] In the present application, the palladium-containing compound and the ligand can be added into the reactor separately to obtain the catalyst in situ.
[0038] The present application also provides a method for preparing 1-methyl octadiene, which uses the catalyst described above and comprises the following steps:
[0039] The butadiene, methanol, a solvent, and the catalyst described above for catalyzing the synthesis of 1-methyl octadiene are mixed and reacted to obtain 1-methyl octadiene.
[0040] In one embodiment, the methanol, the solvent, and the catalyst described above for catalyzing the synthesis of 1-methyl octadiene are mixed first, and then the butadiene is introduced and reacted.
[0041] In one embodiment, the solvent is at least one of organic solvents such as methanol, hexane, and cyclohexane, preferably methanol. The amount of the solvent is not particularly limited in the present application and can be adjusted according to conventional techniques in the art. The source of the butadiene is not particularly limited in the present application, which can be a commercially available product. In another embodiment, the purity of the butadiene is 99.5%.
[0042] In one embodiment, the molar ratio of the palladium-containing compound to the butadiene is 0.005%-0.05%, the molar ratio of the ligand to the butadiene is 0.01%-0.1%, and the molar ratio of the methanol to the butadiene is 1-3:3-1.
[0043] In one embodiment, a promoter is further added to the reaction mixture, which is an alkaline substance such as at least one of sodium methoxide, potassium methoxide, sodium carbonate, potassium carbonate, sodium formate, and sodium hydroxide, preferably sodium methoxide. The molar ratio of the promoter to the butadiene is 0.1%-0.7%.
[0044] In one embodiment, the reaction temperature is 25-110°C, preferably 40-90°C, and the reaction time is 0.5-6h, preferably 1-3h.
[0045] In one embodiment, the reaction is carried out in a high-pressure reactor, but the present application is not limited thereto.
[0046] In the method of the present application, the conversion rate of the raw material butadiene can reach 100%, and the selectivity of 1-MOD can reach 94%. The reaction has a high activity and can be fully reacted in 0.5-6h at a low temperature.
[0047] The technical solutions of the present application will be further described in detail below through specific examples.
[0048] Example 1
[0049] In a 500 mL stainless steel autoclave, add methanol 112 mL, palladium chloride 0.010 g (0.056 mmol), tris (3-fluorophenyl) phosphine 0.027 g (0.085 mmol), sodium methoxide 0.3 g, replace with nitrogen for 3 times, pump in butadiene 56 g, react at 60 ℃ for 4 h, cool down to room temperature and stop the reaction, take 2 mL of the reaction liquid into a headspace bottle, quantify by gas chromatography, the conversion rate of butadiene is 100%, and the selectivity of 1-MOD is 94%.
[0050] Example 2
[0051] In a 500 mL stainless steel autoclave, add methanol 112 mL, palladium chloride 0.010 g (0.056 mmol), tris (3-fluorophenyl) phosphine 0.027 g (0.085 mmol), sodium methoxide 0.3 g, replace with nitrogen for 3 times, pump in butadiene 56 g, react at 60 ℃ for 4 h, cool down to room temperature and stop the reaction, take 2 mL of the reaction liquid into a headspace bottle, quantify by gas chromatography, the conversion rate of butadiene is 100%, and the selectivity of 1-MOD is 94%.
[0052] Example 3
[0053] In a 500 mL stainless steel autoclave, add methanol 112 mL, palladium chloride 0.010 g (0.056 mmol), tris (3-fluorophenyl) phosphine 0.027 g (0.085 mmol), sodium methoxide 0.3 g, replace with nitrogen for 3 times, pump in butadiene 56 g, react at 60 ℃ for 4 h, cool down to room temperature and stop the reaction, take 2 mL of the reaction liquid into a headspace bottle, quantify by gas chromatography, the conversion rate of butadiene is 100%, and the selectivity of 1-MOD is 94%.
[0054] Example 4
[0055] In a 500 mL stainless steel autoclave, add methanol 112 mL, palladium chloride 0.010 g (0.056 mmol), tris (3-fluorophenyl) phosphine 0.027 g (0.085 mmol), sodium methoxide 0.3 g, replace with nitrogen for 3 times, pump in butadiene 56 g, react at 60 ℃ for 4 h, cool down to room temperature and stop the reaction, take 2 mL of the reaction liquid into a headspace bottle, quantify by gas chromatography, the conversion rate of butadiene is 100%, and the selectivity of 1-MOD is 94%.
[0056] Example 5
[0057] In a 500 mL stainless steel autoclave, add methanol 112 mL, palladium chloride 0.030 g (0.168 mmol), tris(3-fluorophenyl)phosphine 0.027 g (0.085 mmol), sodium methoxide 0.3 g, replace with nitrogen for 3 times, pump in butadiene 56 g, react at 60 °C for 4 h, cool down to room temperature and stop the reaction, take 2 mL of the reaction liquid into a headspace bottle, quantify by gas chromatography, the conversion of butadiene is 100%, the selectivity of 1-MOD is 88%.
[0058] Example 6
[0059] In a 500 mL stainless steel autoclave, add methanol 112 mL, palladium chloride 0.010 g (0.056 mmol), tris(2-fluorophenyl)phosphine 0.027 g (0.085 mmol), sodium methoxide 0.3 g, replace with nitrogen for 3 times, pump in butadiene 56 g, react at 60 °C for 4 h, cool down to room temperature and stop the reaction, take 2 mL of the reaction liquid into a headspace bottle, quantify by gas chromatography, the conversion of butadiene is 95%, the selectivity of 1-MOD is 91%.
[0060] Example 7
[0061] In a 500 mL stainless steel autoclave, add methanol 112 mL, palladium chloride 0.010 g (0.056 mmol), tris(pentafluorophenyl)phosphine 0.045 g (0.085 mmol), sodium methoxide 0.3 g, replace with nitrogen for 3 times, pump in butadiene 56 g, react at 60 °C for 4 h, cool down to room temperature and stop the reaction, take 2 mL of the reaction liquid into a headspace bottle, quantify by gas chromatography, the conversion of butadiene is 100%, the selectivity of 1-MOD is 85%.
[0062] Example 8
[0063] In a 500 mL stainless steel autoclave, add methanol 112 mL, palladium chloride 0.010 g (0.056 mmol), tris(3-fluorophenyl)phosphine 0.054 g (0.17 mmol), sodium methoxide 0.3 g, replace with nitrogen for 3 times, pump in butadiene 56 g, react at 60 °C for 4 h, cool down to room temperature and stop the reaction, take 2 mL of the reaction liquid into a headspace bottle, quantify by gas chromatography, the conversion of butadiene is 92%, the selectivity of 1-MOD is 95%.
[0064] Example 9
[0065] In a 500 mL stainless steel autoclave, add methanol 112 mL, palladium chloride 0.010 g (0.056 mmol), tris(3-fluorophenyl)phosphine 0.081 g (0.255 mmol), sodium methoxide 0.3 g, replace with nitrogen for 3 times, pump in butadiene 56 g, react at 60 °C for 4 h, cool down to room temperature and stop the reaction, take 2 mL of the reaction liquid into a headspace bottle, quantify by gas chromatography, the conversion of butadiene is 90%, the selectivity of 1-MOD is 96%.
[0066] Example 10
[0067] In a 500 mL stainless steel autoclave, add methanol 112 mL, palladium chloride 0.010 g (0.056 mmol), tris(3-fluorophenyl)phosphine 0.027 g (0.085 mmol), sodium methoxide 0.15 g, replace with nitrogen for 3 times, pump in butadiene 56 g, react at 60 °C for 4 h, cool down to room temperature and stop the reaction, take 2 mL of the reaction liquid into a headspace bottle, quantify by gas chromatography, the conversion of butadiene is 96%, the selectivity of 1-MOD is 92%.
[0068] Example 11
[0069] In a 500 mL stainless steel autoclave, add methanol 112 mL, palladium chloride 0.010 g (0.056 mmol), tris(3-fluorophenyl)phosphine 0.027 g (0.085 mmol), sodium methoxide 0.10 g, replace with nitrogen for 3 times, pump in butadiene 56 g, react at 60 °C for 4 h, cool down to room temperature and stop the reaction, take 2 mL of the reaction liquid into a headspace bottle, quantify by gas chromatography, the conversion of butadiene is 91%, the selectivity of 1-MOD is 89%.
[0070] Example 12
[0071] In a 500 mL stainless steel autoclave, add methanol 112 mL, palladium chloride 0.010 g (0.056 mmol), tris(3-fluorophenyl)phosphine 0.027 g (0.085 mmol), sodium methoxide 0.3 g, replace with nitrogen for 3 times, pump in butadiene 56 g, react at 100 °C for 4 h, cool down to room temperature and stop the reaction, take 2 mL of the reaction liquid into a headspace bottle, quantify by gas chromatography, the conversion of butadiene is 100%, the selectivity of 1-MOD is 87%.
[0072] Example 13
[0073] In a 500 mL stainless steel autoclave, methanol 112 mL, palladium chloride 0.010 g (0.056 mmol), tri(3-fluorophenyl)phosphine 0.027 g (0.085 mmol), sodium methoxide 0.3 g, nitrogen replacement for 3 times, butadiene 56 g was pumped in, 60 °C for 3 h, cooling to room temperature and stopping the reaction, 2 mL of the reaction liquid was taken into a headspace bottle, quantified by gas chromatography, butadiene conversion was 97%, the selectivity of 1-MOD was 94%.
[0074] Example 14
[0075] In a 500 mL stainless steel autoclave, methanol 112 mL, palladium chloride 0.010 g (0.056 mmol), tri(3-fluorophenyl)phosphine 0.027 g (0.085 mmol), sodium methoxide 0.3 g, nitrogen replacement for 3 times, butadiene 56 g was pumped in, 60 °C for 6 h, cooling to room temperature and stopping the reaction, 2 mL of the reaction liquid was taken into a headspace bottle, quantified by gas chromatography, butadiene conversion was 100%, the selectivity of 1-MOD was 93%.
[0076] Example 15
[0077] In a 500 mL stainless steel autoclave, methanol 112 mL, palladium chloride 0.010 g (0.056 mmol), tri(3-fluorophenyl)phosphine 0.027 g (0.085 mmol), sodium methoxide 0.3 g, nitrogen replacement for 3 times, butadiene 56 g was pumped in, 60 °C for 6 h, cooling to room temperature and stopping the reaction, 2 mL of the reaction liquid was taken into a headspace bottle, quantified by gas chromatography, butadiene conversion was 100%, the selectivity of 1-MOD was 94%.
[0078] Comparative Example 1
[0079] In a 500 mL stainless steel autoclave, methanol 112 mL, palladium chloride 0.010 g (0.056 mmol), tri(3-fluorophenyl)phosphine 0.027 g (0.085 mmol), sodium methoxide 0.3 g, nitrogen replacement for 3 times, butadiene 56 g was pumped in, 60 °C for 4 h, cooling to room temperature and stopping the reaction, 2 mL of the reaction liquid was taken into a headspace bottle, quantified by gas chromatography, butadiene conversion was 85%, the selectivity of 1-MOD was 90%.
[0080] Comparative Example 2
[0081] In a 500 mL stainless steel autoclave, 112 mL of methanol, 0.017 g (0.056 mmol) of palladium acetylacetonate, 0.027 g (0.085 mmol) of triphenylphosphine, and 0.3 g of sodium methoxide were added. The mixture was purged with nitrogen three times, and 56 g of butadiene was pumped in. The reaction was carried out at 60 °C for 4 h. The mixture was then cooled to room temperature and the reaction was stopped. 2 mL of the reaction solution was transferred to a headspace vial and quantified by gas chromatography. The butadiene conversion rate was 81%, and the selectivity for 1-MOD was 83%.
[0082] Comparative Example 3
[0083] In a 500 mL stainless steel autoclave, 112 mL of methanol, 0.0126 g (0.056 mmol) of palladium acetate, 0.027 g (0.085 mmol) of triphenylphosphine, and 0.3 g of sodium methoxide were added. The mixture was purged with nitrogen three times, and 56 g of butadiene was pumped in. The reaction was carried out at 60 °C for 4 h. The mixture was then cooled to room temperature and the reaction was stopped. 2 mL of the reaction solution was transferred to a headspace vial and quantified by gas chromatography. The butadiene conversion rate was 65%, and the selectivity for 1-MOD was 90%.
[0084] Of course, the present invention may have other various embodiments. Without departing from the spirit and essence of the present invention, those skilled in the art can make various corresponding changes and modifications according to the present invention, but these corresponding changes and modifications should all fall within the protection scope of the claims of the present invention.
Claims
1. A catalyst for the catalytic synthesis of octadiene monomethyl ether, characterized in that, It includes a palladium-containing compound and a ligand, said ligand having the structure of Formula I: Among them, the substituents R1, R2, R3, R4, R5, R6, R7, R8, R9, R 10 R 11 R 12 R 13 R 14 R 15 It is independently selected from fluorine, methyl and hydrogen, and at least one substituent is fluorine.
2. The catalyst for the catalytic synthesis of octadiene monomethyl ether according to claim 1, characterized in that, The molar ratio of the palladium-containing compound to the ligand is 0.5-5:1-10; the palladium-containing compound is at least one of palladium acetylacetone, palladium acetate, and palladium chloride.
3. A method for preparing octadiene monomethyl ether, characterized in that, Includes the following steps: Butadiene, methanol, solvent and the catalyst for the catalytic synthesis of octadiene monomethyl ether as described in claim 1 or 2 are mixed and reacted to obtain octadiene monomethyl ether.
4. The method for preparing octadiene monomethyl ether according to claim 3, characterized in that, The solvent is at least one of methanol, hexane, and cyclohexane.
5. The method for preparing octadiene monomethyl ether according to claim 3, characterized in that, The molar ratio of the palladium-containing compound to butadiene is 0.005%-0.05%.
6. The method for preparing octadiene monomethyl ether according to claim 3, characterized in that, The molar ratio of the ligand to butadiene is 0.01%-0.1%.
7. The method for preparing octadiene monomethyl ether according to claim 3, characterized in that, An accelerator, which is an alkaline substance, was also added to the reaction mixture, and the molar ratio of the accelerator to butadiene was 0.1%-0.7%.
8. The method for preparing octadiene monomethyl ether according to claim 7, characterized in that, The accelerator is at least one of sodium methoxide, potassium methoxide, sodium carbonate, potassium carbonate, sodium formate, and sodium hydroxide.
9. The method for preparing octadiene monomethyl ether according to claim 3, characterized in that, The reaction temperature is 25-110℃, and the reaction time is 0.5-6h.
10. The method for preparing octadiene monomethyl ether according to claim 3, characterized in that, The molar ratio of methanol to butadiene is 1-3:3-1.