Process for hydroformylation of olefins

Abstract

The invention provides an olefin hydroformylation method. The method comprises the following steps: mixing CO, H2, an olefin raw material and a complex catalyst to obtain a mixed raw material, and carrying out a hydroformylation reaction to obtain an aldehyde product; the complex catalyst comprises a transition metal raw material and a phosphite ester type bidentate phosphine ligand containing an aryl ether structure, and the phosphite ester type bidentate phosphine ligand containing the aryl ether structure has a structure as shown in a general formula (1). By optimizing the structure of the phosphine ligand of the catalyst, the hydroformylation reaction can realize higher conversion rate, higher selectivity and higher normal / isomeric ratio under the conditions of low reaction pressure and low reaction temperature; in the industrial application process, the method disclosed by the invention has the advantages of low metal loss and low ligand loss, and the operation cost of the device can be remarkably reduced; the production efficiency of a target product can be remarkably improved through the high normal-different ratio, the production cost is reduced, the product performance is more stable, and market popularization is facilitated.

Description

Technical Field

[0001] The invention relates to the technical field of coal chemical industry, and in particular to a method for hydroformylation of olefins. Background Art

[0002] The hydroformylation reaction is a reaction in which olefins react with carbon monoxide and hydrogen in the presence of a catalyst to generate an aldehyde with one more carbon atom than the raw olefin. Aldehydes are important intermediates that can be further processed into high-value-added fine chemicals, such as alcohols, carboxylic acids and other chemicals, plasticizers, edible flavors, pharmaceutical intermediates, etc., with high economic value and application value. The low-carbon alcohols (C3-C4) obtained by aldehyde reduction are used to produce solvents, intermediate alcohols (C5-C12) are used as plasticizers, and higher alcohols (C13-C17) can be converted into surfactants. Therefore, the hydroformylation reaction of olefins has received widespread attention.

[0003] Butene is hydroformylated to synthesize valeraldehyde, which is then condensed and hydrogenated to generate a plasticizer alcohol with excellent performance, namely 2-propylheptyl alcohol (2-PH). The plasticizer di(2-propylheptyl) phthalate (DPHP) synthesized from 2-PH has low volatility, is beneficial to environmental protection, and can be used to produce plastics with good weather resistance and thermal stability. It is also a new method for comprehensive utilization of butene and increasing economic benefits. However, most of the valeraldehyde raw materials currently rely on imports or self-built small-scale production equipment for small-scale production. In recent years, the demand for valeraldehyde has increased year by year, and the demand for its downstream products has also shown an increasing trend year by year. Simply relying on imports is far from meeting the increasing domestic demand. Therefore, realizing independent large-scale production of valeraldehyde and exploring a technology for the utilization of butene hydroformylation that is adapted to local conditions have become the focus of attention. The C5-C12 products produced by the OXO process are also used as plasticizer alcohols. This family is mainly composed of isononyl alcohol, isodecanol and linear C7-C11 alcohols. n-Butanol or its derivatives (ie, butyl acetate, butyl acrylate, or ethylene glycol butyl ester) are used as solvents or surface coating additives.

[0004] The metal active center used in the catalyst for the hydroformylation of butene is mainly a transition metal of the main group VIII that can form carbonyl compounds, but the activity of different metals varies greatly. Cobalt (Co), rhodium (Rh), platinum (Pt), and ruthenium (Ru) are the four metals with the highest activity for the hydroformylation of olefins. At present, industrial catalysts are based on compounds of cobalt and rhodium, and platinum and ruthenium are only used in laboratory research. The first generation of catalysts is a carbonyl cobalt catalyst or a carbonyl cobalt catalyst modified by a tertiary phosphine ligand, the second generation of catalysts is a low-pressure rhodium-phosphine complex catalyst, and the third generation of catalysts is a water-soluble rhodium-phosphine complex catalyst. The prior art also uses phosphite ligands instead of the original triphenylphosphine ligands for the hydroformylation of butene to synthesize valeraldehyde, and obtains a higher reaction rate and selectivity. The rhodium catalyst modified by the phosphite ligand has a decisive advantage over the traditional olefin hydroformylation catalyst in catalyzing the butene reaction, and has extraordinary activity and regioselectivity in the olefin hydroformylation reaction. In recent years, people have devoted themselves to studying the role of phosphite ligands and phosphinamide ligands in olefin hydroformylation, and have improved the stability of catalyst ligands, the activity of the reaction, and the selectivity of linear aldehydes by combining ligands, changing the structure of ligands, and adding second metals.

[0005] Chinese patent CN102574878A discloses a gas phase hydroformylation method, in which an aldehyde product is prepared in the presence of a transition metal-ligand complex hydroformylation catalyst and water vapor, wherein the ligand includes an organic phosphite ligand, the catalyst is physically adsorbed on a carrier, a trace amount of water is included in the feed stream to maintain the catalyst activity, and the catalyst can be regenerated by treating the catalyst with a buffer. Chinese patent CN111344274A discloses a hydroformylation method, invents a hydroformylation method for reducing the recycle flow of a rhodium-phosphite complex catalyst, and during liquid recirculation, the precipitation of rhodium in the complex catalyst solution is minimized or can be avoided. Chinese patent CN13385236A discloses an olefin hydroformylation catalyst composition and a hydroformylation method, using a catalyst composition comprising three components, the three components being a metal complex with a monophosphite (or monodentate phosphite) as a ligand, a free monophosphite (or monodentate phosphite) ligand, and a trivalent organic phosphine compound.

[0006] However, in the process of industrial application of the above technical solution, there is still a lot of metal loss and ligand loss in the catalyst, resulting in high production costs. In addition, the reaction conditions are relatively harsh, the reaction selectivity and positive-isolation are relatively low, and the product performance is unstable. Summary of the invention

[0007] The main purpose of the present invention is to provide a method for olefin hydroformylation to solve the problems of high cost and poor product performance caused by high metal loss and ligand loss of olefin hydroformylation catalyst in the prior art.

[0008] In order to achieve the above object, according to one aspect of the present invention, a method for hydroformylation of olefins is provided, wherein CO, H2, an olefin raw material and a complex catalyst are mixed to obtain a mixed raw material, and then a hydroformylation reaction is carried out to obtain an aldehyde product; the complex catalyst comprises a transition metal raw material and a phosphite-type bidentate phosphine ligand containing an aromatic ether structure, and the phosphite-type bidentate phosphine ligand containing an aromatic ether structure has a structure shown in the general formula (1):

[0009]

[0010] Among them, X 1 , X 2 and X 3 are independently selected from a blank, O, S; R 1 , R 2 , R 3 , R 4 , R 5 and R 6 are independently selected from hydrogen, halogen, substituted or unsubstituted C1-C10 straight or branched alkyl, substituted or unsubstituted adamantyl, substituted or unsubstituted C6-C18 aryl; Ar 1 ,Ar 2 ,Ar 3 and Ar 4 Each is independently selected from substituted or unsubstituted C6-C18 aryl groups.

[0011] Furthermore, in the general formula (1), R 1 , R 2 , R 3 , R 4 , R 5 and R 6 are independently selected from hydrogen, halogen, substituted or unsubstituted C1-C4 straight-chain alkyl, substituted or unsubstituted adamantyl, substituted or unsubstituted C6-C12 aryl; preferably, R 1 , R 3 , R 4 and R 6 are independently selected from substituted or unsubstituted adamantyl; and / or Ar 1 ,Ar 2 ,Ar 3 and Ar 4 Each is independently selected from substituted or unsubstituted C6-C12 aryl groups.

[0012] Furthermore, the phosphite-type bidentate phosphine ligand containing an aromatic ether structure has a structure shown in general formula (2):

[0013]

[0014] Among them, X 1 , X 2 , X 3 are independently selected from O, S; R 1 , R 2 , R 3 , R 4 , R 5 , R 6 , R 7 , R 8 , R 9 , R 10 , R 11 , R 12 , R 13 , R 14 , R 15 , R 16 , R 17 , R 18 , R 19 , R 20 , R 21 and R 22 Each is independently selected from hydrogen, halogen, substituted or unsubstituted C1-C10 straight or branched alkyl, substituted or unsubstituted adamantyl, and substituted or unsubstituted C6-C18 aryl.

[0015] Furthermore, in the general formula (2), R 1 , R 2 , R 3 , R 4 , R 5 , R 6 , R 7 , R 8 , R 9 , R 10 , R 11 , R 12 , R 13 , R 14 , R 15 , R 16 , R 17 , R 18 , R 19 , R 20 , R 21 and R 22 are independently selected from hydrogen, halogen, substituted or unsubstituted C1-C4 straight-chain alkyl, substituted or unsubstituted adamantyl, substituted or unsubstituted C6-C12 aryl; preferably, R 1 , R 3 , R 4 and R 6 are each independently selected from a substituted or unsubstituted adamantyl group.

[0016] Furthermore, the phosphite-type bidentate phosphine ligand containing an aryl ether structure has the following structure:

[0017]

[0018] Furthermore, the molar ratio of the transition metal in the transition metal raw material to the phosphite-type bidentate phosphine ligand containing an aromatic ether structure is 1:(2-50), preferably 1:(7-15); and / or the molar ratio of the olefin raw material to the complex catalyst is (1000-10000):1.

[0019] Furthermore, the mass concentration of the transition metal in the transition metal raw material is 1 to 1000 ppm in the mixed raw material; and / or the transition metal in the transition metal raw material includes one or more of iron, cobalt, nickel, ruthenium, rhodium, palladium, osmium, iridium and platinum; preferably, the transition metal raw material includes one or more of acetylacetonato dicarbonyl rhodium, rhodium chloride and rhodium acetate.

[0020] Furthermore, the temperature of the hydroformylation reaction is 20-200° C., and the time is 3-5 h; and / or the sum of the pressures of CO and H2 is 0.5-6 MPa, and the pressure ratio of CO and H2 is 1:(0.1-10).

[0021] Further, the olefin feedstock comprises olefins and / or alkane-olefin mixtures, the olefins being selected from C2 to C25 α-olefins or internal olefins; and / or the alkane-olefin mixture comprises, by weight percentage, 38 to 33% of n-undecane, 20 to 25% of n-dodecane, 20 to 25% of 1-undecene and 20 to 25% of 1-dodecene; preferably, the olefins comprise n-pentene and / or 2-butene.

[0022] Furthermore, the aldehyde product includes normal aldehyde and isomeric aldehyde, and the molar ratio of normal aldehyde to isomeric aldehyde is (10-50):1.

[0023] By applying the technical solution of the present invention, the structure of the catalyst phosphine ligand is optimized, so that the hydroformylation reaction can achieve a higher conversion rate, higher selectivity and higher normal-iso ratio under the conditions of low reaction pressure and low reaction temperature. In the process of industrial application, the method of the present invention has the advantages of less metal loss and less ligand loss, and can significantly reduce the operating cost of the device. A higher normal-iso ratio can significantly improve the production efficiency of the target product, reduce the production cost, make the product performance more stable, and facilitate market promotion. DETAILED DESCRIPTION

[0024] It should be noted that, in the absence of conflict, the embodiments and features in the embodiments of the present application can be combined with each other. The present invention will be described in detail below in conjunction with the embodiments.

[0025] As described in the background of the present invention, the prior art has the problem of high metal loss and ligand loss in olefin hydroformylation catalysts, resulting in high cost and poor product performance. In order to solve the above problems, in a typical embodiment of the present invention, a method for olefin hydroformylation is provided, CO, H2, olefin raw materials and complex catalysts are mixed to obtain a mixed raw material, which is used for hydroformylation reaction to obtain an aldehyde product; the complex catalyst includes a transition metal raw material and a phosphite-type bidentate phosphine ligand containing an aromatic ether structure, and the phosphite-type bidentate phosphine ligand containing an aromatic ether structure has a structure shown in the general formula (1):

[0026]

[0027] Among them, X 1 , X 2 and X 3 are independently selected from a blank, O, S; R 1 , R 2 , R 3 , R 4 , R 5 and R 6 are independently selected from hydrogen, halogen, substituted or unsubstituted C1-C10 straight or branched alkyl, substituted or unsubstituted adamantyl, substituted or unsubstituted C6-C18 aryl; Ar 1 ,Ar 2 ,Ar 3 and Ar 4 Each is independently selected from substituted or unsubstituted C6-C18 aryl groups.

[0028] In the olefin hydroformylation reaction, the stability of the catalyst directly affects the metal loss and ligand loss, which in turn affects the cost and efficiency of the reaction. The active center of the catalyst is usually a transition metal, and its binding tightness and stability with the ligand are crucial. The present invention optimizes the structure of the catalyst phosphine ligand, wherein the transition metal forms a complex with a phosphite-type bidentate phosphine ligand containing an aryl ether structure.

[0029] The specific structural selection of the above-mentioned ligand can reduce metal loss and ligand loss, thereby significantly reducing production costs. The stability of the catalyst in the reaction increases, which means that its life is extended, and it is not necessary to frequently replenish or replace it, thereby reducing the usage of expensive transition metals and ligands and reducing the operating costs of the device. In addition, the reaction can be carried out at a lower reaction pressure and temperature, which also helps to reduce energy consumption and further reduce production costs. The specific structural selection of the above-mentioned ligand can also significantly improve the conversion rate and selectivity of olefin hydroformylation reaction. This is because the ligand of the above-mentioned specific structure can more effectively stabilize the transition metal active center, promote the reaction along the target path, and suppress undesirable side reactions. The increase in the ratio of normal / isomerized product aldehydes (i.e., normal-isomeric ratio) means that the product distribution is more inclined to normal aldehydes, which is very valuable in industrial applications because normal aldehydes usually have better physical properties and higher market demand.

[0030] The present invention improves the conditions of the hydroformylation reaction by optimizing the structure of the catalyst phosphine ligand and enhancing the stability and activity of the catalyst, that is, achieving a higher conversion rate, selectivity and normal-iso ratio at a lower reaction pressure and temperature, thereby improving product performance, while significantly reducing the loss of metals and ligands, and ultimately reducing production costs, so that the hydroformylation reaction can achieve a higher conversion rate, higher selectivity and higher normal-iso ratio under the conditions of low reaction pressure and low reaction temperature. In the process of industrial application, the method of the present invention has the advantages of less metal loss and less ligand loss, and can significantly reduce the operating cost of the device. A higher normal-iso ratio can significantly improve the production efficiency of the target product, reduce production costs, make product performance more stable, and be conducive to market promotion.

[0031] In a preferred embodiment, in the general formula (1), R 1 , R 2 , R 3 , R 4 , R 5 and R 6 are independently selected from hydrogen, halogen, substituted or unsubstituted C1-C4 straight-chain alkyl, substituted or unsubstituted adamantyl, substituted or unsubstituted C6-C12 aryl; preferably, R 1 , R 3 , R 4 and R 6 are independently selected from substituted or unsubstituted adamantyl; and / or Ar 1 ,Ar 2 ,Ar 3 and Ar 4 They are independently selected from substituted or unsubstituted C6-C12 aromatic groups. The selection of the above ligand structure is beneficial to further improve the activity, selectivity and stability of the catalyst, so as to further reduce the catalyst loss and reduce the cost.

[0032] In particular, the steric effect of the adamantyl group can provide additional protection to prevent the transition metal active center from being oxidized or reacting unnecessarily with other reactants, thereby reducing metal loss. In addition, its three-dimensional structure helps maintain the conformational stability of the catalyst, preventing the ligand from falling off the metal center, thereby reducing ligand loss. The electronic properties and steric hindrance of the C6-C12 aromatic groups have a significant effect on the activity of the catalyst. These groups can provide electrons to the transition metal center, enhancing its catalytic activity. At the same time, the larger steric hindrance can prevent side reactants from approaching the active center, thereby improving the selectivity of the target product (normal aldehyde). This is also conducive to maintaining the stability of the catalyst at low reaction temperature and pressure. The larger spatial structure can also resist structural distortion or damage caused by changes in temperature and pressure.

[0033] In order to further improve product performance, reduce costs, and make the hydroformylation process more economical and environmentally friendly, in a preferred embodiment, the phosphite-type bidentate phosphine ligand containing an aromatic ether structure has a structure shown in general formula (2):

[0034]

[0035] Among them, X 1 , X 2 , X 3 are independently selected from O, S; R 1 , R 2 , R 3 , R 4 , R 5 , R 6 , R 7 , R 8 , R 9 , R 10 , R 11 , R 12 , R 13 , R 14 , R 15 , R 16 , R 17 , R 18 , R 19 , R 20 , R 21 and R 22 Each is independently selected from hydrogen, halogen, substituted or unsubstituted C1-C10 straight or branched alkyl, substituted or unsubstituted adamantyl, and substituted or unsubstituted C6-C18 aryl.

[0036] In the above structure, by introducing electron-donating groups with large steric hindrance, the catalytic performance of the metal active center can be improved, the stability of the complex structure can be enhanced, and the metal loss and ligand loss can be further reduced, which is conducive to the hydroformylation reaction being carried out efficiently under low reaction pressure and low reaction temperature conditions. 1 , X 2 , X 3 The selection of the R group can optimize the electronic properties and steric hindrance of the ligand, thereby enhancing the stability and activity of the catalyst. O and S, as electron donors, can effectively stabilize the transition metal center and reduce metal loss; at the same time, their soft and hard acid-base properties help to regulate the catalytic activity and achieve efficient catalysis at low reaction pressure and temperature. C1-C10 straight-chain or branched alkyl groups and C6-C18 aromatic groups can protect the metal active center from interference by side reactants through steric hindrance, improve the selectivity of normal aldehydes, and reduce the desorption of ligands and losses.

[0037] In a preferred embodiment, in the general formula (2), R 1 , R 2 , R 3 , R 4 , R 5 , R 6 , R 7 , R 8 , R 9 , R 10 , R 11 , R 12 , R 13 , R 14 , R 15 , R 16 , R 17 , R 18 , R 19 , R 20 , R 21 and R 22 are independently selected from hydrogen, halogen, substituted or unsubstituted C1-C4 straight-chain alkyl, substituted or unsubstituted adamantyl, substituted or unsubstituted C6-C12 aryl; preferably, R 1 , R 3 , R 4 and R 6 The specific selection of the R group can further stabilize the complex state of the catalyst, reduce the desorption of the ligand under the reaction conditions, reduce the ligand loss, and help maintain high activity at a lower reaction pressure and temperature, achieve efficient conversion, improve the selectivity of the target product, further improve the iso-ratio, and optimize product performance.

[0038] Based on the above reasons, it is most preferred that, in a preferred embodiment, the phosphite-type bidentate phosphine ligand containing an aryl ether structure has the following structure:

[0039] In this structure, by introducing an electron-donating group with greater steric hindrance, the catalytic performance of the metal active center can be further improved, and the stability of the complex structure can be better enhanced, thereby further reducing metal loss and ligand loss, and being more conducive to the hydroformylation reaction to achieve a higher conversion rate, higher selectivity and higher isocyanate ratio under low reaction pressure and low reaction temperature conditions.

[0040] In a preferred embodiment, the molar ratio of the transition metal in the transition metal raw material to the bidentate phosphine ligand containing the aryl ether structure is 1: (2-50); and / or the molar ratio of the olefin raw material to the complex catalyst is (1000-10000): 1. Within the above molar ratio range, the activity and stability of the catalyst can be more finely regulated, reducing metal loss and ligand loss, thereby reducing costs. At lower metal concentrations, increasing the proportion of ligands can more effectively surround and stabilize the metal active center to prevent it from being lost during the reaction. At the same time, the optimized ligand environment helps to maintain the efficient activity of the catalyst under mild conditions (low pressure, low temperature) and achieve higher conversion rate and selectivity. In addition, the molar ratio of the olefin raw material to the complex catalyst is reasonably adjusted to improve the full utilization rate of the catalyst, reduce the passivation of the active center caused by excess olefins or unnecessary side reactions caused by excess ligands, further improve the positive iso ratio, and optimize product performance. The above conditions can significantly improve the controllability of the reaction and product quality while maximizing economic benefits.

[0041] For the purpose of better realizing an efficient, economical and environmentally friendly hydroformylation reaction process, in a preferred embodiment, the transition metal in the transition metal raw material accounts for 1 to 1000 ppm of the mass concentration of the mixed raw material; and / or the transition metal in the transition metal raw material includes one or more of iron, cobalt, nickel, ruthenium, rhodium, palladium, osmium, iridium and platinum; preferably, the transition metal raw material includes one or more of acetylacetonato dicarbonyl rhodium, rhodium chloride and rhodium acetate. Controlling the transition metal concentration within the above range can provide more effective activity and further reduce the self-aggregation or passivation of the catalyst that may occur at high concentrations, thereby reducing metal loss. These Group VIII B metals have the ability to form efficient carbonyl compounds, which can significantly improve the conversion rate and positive-isomer ratio, while maintaining a low reaction temperature and pressure, reducing energy consumption, reducing side reactions, and thus reducing ligand loss. Specific metal complexes such as acetylacetonato dicarbonyl rhodium can provide more stable active centers due to their structural characteristics, further reducing metal loss and improving the selectivity of the reaction.

[0042] In a preferred embodiment, the temperature of the hydroformylation reaction is 20 to 200°C, and the time is 3 to 5 hours; and / or the sum of the pressures of CO and H2 is 0.5 to 6 MPa, and the pressure ratio of CO and H2 is 1:(0.1 to 10). Lower reaction temperature and pressure are conducive to reducing the thermodynamic and mechanical burden of the catalyst, enhancing the stability of the catalyst, reducing the degradation of the metal active center and the dissociation of the ligand, thereby reducing metal loss and ligand loss, and directly reducing production costs. At the same time, mild reaction conditions are conducive to maintaining a high conversion rate and selectivity, especially under low pressure. By finely controlling the pressure ratio of CO and H2, the proportion of normal aldehydes in the product (normal-iso ratio) can be effectively increased. Under the above conditions, the reaction can be made more efficient, more economical, and environmentally friendly, which is more conducive to the industrial application of the hydroformylation process.

[0043] In order to further maintain the high conversion rate of the reaction at low pressure and low temperature, in a preferred embodiment, the olefin raw material includes olefins and / or alkane-olefin mixtures, and the olefins are selected from C2 to C25 α-olefins or internal olefins; and / or the alkane-olefin mixture includes 38 to 33% of n-undecane, 20 to 25% of n-dodecane, 20 to 25% of 1-undecene and 20 to 25% of 1-dodecene in terms of weight percentage; preferably, the olefins include n-pentene and / or 2-butene. Due to their structural characteristics, the above-mentioned olefin raw materials can form more stable intermediates with the catalyst, reduce side reactions, especially reduce excessive consumption of highly active metal centers, and effectively control metal loss. At the same time, the increase in the proportion of normal olefins in the raw materials helps to increase the generation of normal aldehydes, improve the normal-iso ratio, and optimize product selectivity.

[0044] In a preferred embodiment, the aldehyde product includes normal aldehyde and isomeric aldehyde, and the molar ratio of normal aldehyde to isomeric aldehyde is (10-50): 1. A higher normal-to-isomeric ratio means that the selectivity for generating the target normal aldehyde during the reaction is enhanced, thereby improving the purity and performance of the product.

[0045] The present application is further described in detail below in conjunction with specific embodiments. These embodiments should not be construed as limiting the scope of protection claimed in the present application.

[0046] The structure of the phosphite-type bidentate phosphine ligand containing an aryl ether structure used in the following examples is as follows:

[0047] Ligand A: The ligand can be obtained by adopting a general preparation method of a phosphite bidentate phosphine ligand and changing the raw materials accordingly.

[0048] Examples 1 to 4

[0049] In a 1L autoclave, add acetylacetonato dicarbonyl rhodium (the amount added is 200ppm based on the mass of pure rhodium), the molar amount of ligand A added is 3, 7, 10 and 15 times the molar amount of rhodium, add 100mL of n-pentene to the autoclave, fully replace the autoclave with hydrogen at low temperature, and return to room temperature after the replacement is completed. Pressurize the autoclave to 1.5MPa with hydrogen, and then pressurize the total pressure of the autoclave to 3.0MPa (the partial pressure of carbon monoxide is 1.5MPa) with carbon monoxide. Heat and stir the autoclave, and react at a constant temperature for 3 hours when the reaction temperature reaches 85°C. After the reaction is completed, cool to room temperature, release the remaining pressure in the fume hood, open the autoclave, take samples and analyze the product composition by gas chromatography. The results are as follows:

[0050] Table 1

[0051] Example Ligand A / molar multiple Aldehyde conversion rate / % n-Hexanal:2-Methylvaleraldehyde (molar ratio) 1 3 54.6 16 2 7 77.2 22 3 10 86.7 35 4 15 95.3 42

[0052] Examples 5 to 8

[0053] In a 1L autoclave, add acetylacetonato dicarbonyl rhodium (the amount added is 240ppm based on the mass of pure rhodium), the added molar amount of ligand A is 3, 7, 10 and 15 times the molar amount of rhodium, add 100mL 2-butene to the reactor, fully replace the autoclave with hydrogen at low temperature, and return to room temperature after the replacement is completed. Pressurize the autoclave to 1.0MPa with hydrogen, and then pressurize the total pressure of the autoclave to 1.5MPa (the partial pressure of carbon monoxide is 0.5MPa) with carbon monoxide. Heat and stir the autoclave, and react at a constant temperature for 3 hours when the reaction temperature reaches 75°C. After the reaction is completed, cool to room temperature, release the remaining pressure in the fume hood, open the reactor, take samples and analyze the product composition with gas chromatography, the results are as follows:

[0054] Table 2

[0055] Example Ligand A / molar multiple Aldehyde conversion rate / % n-Hexanal:2-Methylvaleraldehyde (molar ratio) 5 3 34.1 12 6 7 72.3 22 7 10 88.9 33 8 15 96.7 41

[0056] Examples 9 to 12

[0057] In a 1L autoclave, add acetylacetonato dicarbonyl rhodium (the amount added is 350ppm based on the mass of pure rhodium), the added molar amount of ligand A is 3, 7, 10 and 15 times the molar amount of rhodium, add 100mL of alkene mixture (31% of n-undecane, 24% of n-dodecane, 23% of 1-undecene, 21% of 1-dodecene, and the balance is other substances) to the autoclave, and replace the autoclave with hydrogen. Pressurize the autoclave to 1.5MPa with hydrogen, and then pressurize the total pressure of the autoclave to 3.0MPa (the partial pressure of carbon monoxide is 1.5MPa) with carbon monoxide. Heat and stir the autoclave, and react at a constant temperature for 5 hours when the reaction temperature reaches 110°C. After the reaction is completed, cool to room temperature, release the remaining pressure in the fume hood, open the autoclave, and analyze the product composition with gas chromatography after sampling. The results are as follows:

[0058] Table 3

[0059] Example Ligand A / molar multiple Aldehyde conversion rate / % n-Hexanal:2-Methylvaleraldehyde (molar ratio) 9 3 32.1 12 10 7 50.6 29 11 10 75.1 35 12 15 98.5 47

[0060] Embodiment 13

[0061] In a 1L autoclave, rhodium chloride (the amount added is 1000ppm calculated by the mass of pure rhodium), the added molar amount of ligand A is twice the molar amount of rhodium, 100mL of n-pentene is added to the reactor, the autoclave is fully replaced with hydrogen at low temperature, and the replacement is restored to room temperature. Hydrogen is used to pressurize the autoclave to 0.25MPa, and then the total pressure of the autoclave is pressurized to 0.5MPa (the partial pressure of carbon monoxide is 0.25MPa) with carbon monoxide. The autoclave is heated and stirred, and the reaction temperature is kept at a constant temperature for 5 hours after reaching 20°C. After the reaction is completed, it is cooled to room temperature, and after the remaining pressure is released in the fume hood, the reactor is opened, and the product composition is analyzed by gas chromatography after sampling. The results are shown in Table 4.

[0062] Embodiment 14

[0063] In a 1L autoclave, add rhodium acetate (the amount added is 1ppm based on the mass of pure rhodium), the added molar amount of ligand A is 50 times the molar amount of rhodium, add 100mL of n-pentene to the autoclave, fully replace the autoclave with hydrogen at low temperature, and return to room temperature after the replacement is completed. Pressurize the autoclave to 3MPa with hydrogen, and then pressurize the total pressure of the autoclave to 6MPa (the partial pressure of carbon monoxide is 3MPa) with carbon monoxide. Heat and stir the autoclave, and react at a constant temperature for 3 hours after the reaction temperature reaches 200°C. After the reaction is completed, cool to room temperature, and after the remaining pressure is released in the fume hood, open the autoclave, and analyze the product composition with gas chromatography after sampling. The results are shown in Table 4.

[0064] Table 4

[0065] Example Aldehyde conversion rate / % n-Hexanal:2-Methylvaleraldehyde (molar ratio) 13 25.6 14 14 24.7 40

[0066] Comparative Examples 1 to 4

[0067] In a 1L autoclave, add acetylacetonato dicarbonyl rhodium (the addition amount is 240ppm based on the pure rhodium mass), the added molar amount of triphenylphosphine is 3, 7, 10 and 15 times of the molar amount of rhodium, add 100mL 2-butene to the reactor, fully replace the autoclave with hydrogen at low temperature, and return to room temperature after the replacement is completed. Pressurize the autoclave to 1.0MPa with hydrogen, and then pressurize the total pressure of the autoclave to 1.5MPa (the partial pressure of carbon monoxide is 0.5MPa) with carbon monoxide. Heat and stir the autoclave, and the reaction is carried out at a constant temperature for 5 hours after the reaction temperature reaches 75°C. After the reaction is completed, cool to room temperature, and after the remaining pressure is released in the fume hood, open the reactor, and analyze the product composition with gas chromatography after sampling, and find that no reaction can occur.

[0068] It can be seen from the above examples and comparative examples that the structure of the ligand has a decisive influence on the hydroformylation reaction of olefins. The ligand A in the present invention can not only catalyze the hydroformylation reaction of low-carbon α-olefins and high-carbon α-olefins, but also catalyze the hydroformylation reaction of internal olefins.

[0069] As can be seen from the above, compared with the comparative example, the embodiments of the present invention optimize the structure of the catalyst phosphine ligand, so that the hydroformylation reaction can achieve a higher conversion rate, higher selectivity and higher normal-iso ratio under the conditions of low reaction pressure and low reaction temperature. In the process of industrial application, the method of the present invention has the advantages of less metal loss and less ligand loss, and can significantly reduce the operating cost of the device. A higher normal-iso ratio can significantly improve the production efficiency of the target product, reduce production costs, make product performance more stable, and facilitate market promotion.

[0070] In addition, it can be seen that when each process parameter is within the preferred range of the present invention, the overall effect is better.

[0071] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. For those skilled in the art, the present invention may have various modifications and variations. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present invention shall be included in the protection scope of the present invention.

Claims

1. A method for the hydroformylation of olefins, characterized in that: mixing CO, H2, olefin raw materials and complex catalyst to obtain a mixed raw material for hydroformylation reaction to obtain an aldehyde product; The complex catalyst comprises a transition metal raw material and a phosphite-type bidentate phosphine ligand containing an aromatic ether structure, wherein the phosphite-type bidentate phosphine ligand containing an aromatic ether structure has a structure shown in general formula (1): Among them, X 1 , X 2 and X 3 are independently selected from a blank bond, O, and S; R 1 , R 2 , R 3 , R 4 , R 5 and R 6 Each of the following is independently selected from hydrogen, halogen, substituted or unsubstituted C1-C10 straight or branched alkyl, substituted or unsubstituted adamantyl, substituted or unsubstituted C6-C18 aryl; Ar 1 ,Ar 2 ,Ar 3 and Ar 4 Each is independently selected from substituted or unsubstituted C6-C18 aryl groups.

2. The method according to claim 1, characterized in that In the general formula (1), R 1 , R 2 , R 3 , R 4 , R 5 and R 6 are independently selected from hydrogen, halogen, substituted or unsubstituted C1-C4 straight-chain alkyl, substituted or unsubstituted adamantyl, substituted or unsubstituted C6-C12 aryl; preferably, R 1 , R 3 , R 4 and R 6 are independently selected from substituted or unsubstituted adamantyl groups; and / or Ar 1 ,Ar 2 ,Ar 3 and Ar 4 Each is independently selected from substituted or unsubstituted C6-C12 aryl groups.

3. The method according to claim 1 or 2, characterized in that: The phosphite-type bidentate phosphine ligand containing an aromatic ether structure has a structure shown in general formula (2): Among them, X 1 , X 2 , X 3 are independently selected from O and S; R 1 , R 2 , R 3 , R 4 , R 5 , R 6 , R 7 , R 8 , R 9 , R 10 , R 11 , R 12 , R 13 , R 14 , R 15 , R 16 , R 17 , R 18 , R 19 , R 20 , R 21 and R 22 Each is independently selected from hydrogen, halogen, substituted or unsubstituted C1-C10 straight or branched alkyl, substituted or unsubstituted adamantyl, and substituted or unsubstituted C6-C18 aryl.

4. The method according to any one of claims 1 to 3, characterized in that In the general formula (2), R 1 , R 2 , R 3 , R 4 , R 5 , R 6 , R 7 , R 8 , R 9 , R 10 , R 11 , R 12 , R 13 , R 14 , R 15 , R 16 , R 17 , R 18 , R 19 , R 20 , R 21 and R 22 Each of the following is independently selected from hydrogen, halogen, substituted or unsubstituted C1-C4 straight-chain alkyl, substituted or unsubstituted adamantyl, and substituted or unsubstituted C6-C12 aryl; Preferably, R 1 , R 3 , R 4 and R 6 are each independently selected from a substituted or unsubstituted adamantyl group.

5. The method according to any one of claims 1 to 4, characterized in that The phosphite-type bidentate phosphine ligand containing an aryl ether structure has the following structure:

6. The method according to any one of claims 1 to 5, characterized in that The molar ratio of the transition metal in the transition metal raw material to the phosphite-type bidentate phosphine ligand containing an aromatic ether structure is 1:(2-50), preferably 1:(7-15); and / or The molar ratio of the olefin raw material to the complex catalyst is (1000-10000):

1.

7. The method according to any one of claims 1 to 6, characterized in that The mass concentration of the transition metal in the transition metal raw material in the mixed raw material is 1 to 1000 ppm; and / or The transition metal in the transition metal raw material includes one or more of iron, cobalt, nickel, ruthenium, rhodium, palladium, osmium, iridium and platinum; Preferably, the transition metal raw material includes one or more of rhodium dicarbonyl acetylacetonate, rhodium chloride and rhodium acetate.

8. The method according to any one of claims 1 to 7, characterized in that The hydroformylation reaction temperature is 20-200°C and the reaction time is 3-5h; and / or The sum of the pressures of CO and H2 is 0.5 to 6 MPa, and the pressure ratio of CO and H2 is 1:(0.1 to 10).

9. The method according to any one of claims 1 to 8, characterized in that The olefin raw material comprises olefins and / or alkane-olefin mixtures, wherein the olefins are selected from C2-C25 α-olefins or internal olefins; and / or the alkane-olefin mixture comprises, by weight percentage, 38-33% of n-undecane, 20-25% of n-dodecane, 20-25% of 1-undecene and 20-25% of 1-dodecene; Preferably, the olefin comprises n-pentene and / or 2-butene.

10. The method according to any one of claims 1 to 9, characterized in that The aldehyde product includes normal aldehyde and isomeric aldehyde, and the molar ratio of the normal aldehyde to the isomeric aldehyde is (10-50):1.

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