Phosphorus-containing modified support and method for preparing the same, supported rhodium catalyst and method for preparing and using the same, and method for olefin hydroformylation

Abstract

The present application relates to the field of olefin catalysis, and discloses a phosphorus-containing modified carrier and a preparation method thereof, a supported Rh catalyst and a preparation method and application thereof, and a method for olefin hydroformylation, which comprises the following steps: in the presence of a solvent, mixing and contacting a phosphorus-containing inorganic compound with a carrier raw material, and then sequentially performing drying I and calcination I on the contacted material; the phosphorus-containing inorganic compound is selected from at least one of phosphoric acid, ammonium dihydrogen phosphate, diammonium hydrogen phosphate and ammonium phosphate; the ratio of the mass of the phosphorus-containing inorganic compound to the mass of the carrier raw material is 0.5-4.5:100, calculated according to the amount of phosphorus element. The catalyst provided by the present application has excellent catalytic activity, and the amount of catalyst used in the reaction is relatively low, and the conversion rate of olefins can reach about 95%.

Description

Technical Field

[0001] This invention relates to the field of olefin catalysis technology, specifically to phosphorus-modified supports and their preparation methods, supported Rh catalysts and their preparation methods and applications, and methods for olefin hydroformylation. Background Technology

[0002] Hydroformylation mainly employs a homogeneous reaction system, using phosphine ligand-modified cobalt or rhodium metal complexes as catalysts to catalyze the reaction of olefin molecules with syngas to produce aldehydes.

[0003] Homogeneous catalysts possess excellent catalytic activity and high selectivity (chemoselectivity and regioselectivity), making them the preferred choice for current industrial applications. However, this type of catalyst also has inherent limitations, such as the difficulty in separating the catalyst from the liquid-phase product after the reaction, resulting in high energy consumption. Furthermore, ligand degradation occurs during separation, leading to catalyst deactivation and increasing production costs.

[0004] In contrast, heterogeneous catalysts can be recovered and reused through simple separation methods, making them more attractive for industrial production. However, heterogeneous catalysts currently lag behind homogeneous catalysts in performance; their activity, selectivity, and stability still cannot meet the requirements of practical applications. Therefore, in recent years, academia and industry have conducted extensive work to develop highly active, highly selective, and stable heterogeneous catalysts suitable for industrial application.

[0005] Rhodium-based catalysts have attracted particular attention due to their relatively superior activity.

[0006] The team led by Zhang Xiongfu at Dalian University of Technology disclosed a molecular sieve-encapsulated heterogeneous core-shell Rh-based catalyst, its preparation method, and its application in CN109876847A. This catalyst encapsulates Rh catalytically active species inside an S-1 zeolite molecular sieve to form an Rh@S-1 catalyst. The olefin conversion and aldehyde yield both exceed 95%, and the positive-to-iso ratio of the hydroformylation product can reach 1.1-2.0. Moreover, the catalyst can be recycled.

[0007] The team led by Ding Yunjie at the Dalian Institute of Chemical Physics disclosed a catalyst system for the hydroformylation of propylene to butyraldehyde and a method for using it in CN104667977A. The system uses an organic ligand polymer composed of organic ligand monomers containing phosphorus and vinyl groups as a support to support Rh, which has a high propylene conversion rate and butyraldehyde selectivity.

[0008] The research group of Professor Li Yadong at Tsinghua University (Nano Res., 2014, 7(9), 1364-1369.) prepared a Rh / ZIF-8 supported catalyst using MOF material ZIF-8 as a support. This catalyst has good performance in the hydroformylation reaction of different chain olefins.

[0009] Supports are crucial for the construction of high-performance Rh-based catalysts for heterogeneous olefin hydroformylation reactions. However, the preparation processes of the supports used in the reported systems are relatively cumbersome and complex, limiting their large-scale application.

[0010] Therefore, developing a simple supported Rh-based catalyst that balances catalytic performance with cost is of great significance for promoting the industrial application of heterogeneous hydroformylation technology. Summary of the Invention

[0011] The purpose of this invention is to address the problem that the catalytic activity of existing heterogeneous Rh-based hydroformylation catalysts needs to be improved.

[0012] To achieve the above objectives, a first aspect of the present invention provides a method for preparing a phosphorus-modified support, the method comprising: mixing and contacting a phosphorus-containing inorganic compound with a support raw material in the presence of a solvent, and then subjecting the contacted material to drying I and calcination I in sequence;

[0013] The phosphorus-containing inorganic compound is selected from at least one of phosphoric acid, diammonium dihydrogen phosphate, diammonium hydrogen phosphate, and ammonium phosphate;

[0014] The ratio of the mass of the phosphorus-containing inorganic compound to the mass of the carrier raw material, calculated as phosphorus element, is 0.5-4.5:100.

[0015] A second aspect of the present invention provides a phosphorus-containing modified carrier prepared by the method described in the first aspect.

[0016] A third aspect of the present invention provides a supported Rh catalyst comprising a support and an active component supported on the support; wherein the active component comprises Rh.

[0017] The carrier is the phosphorus-containing modified carrier described in the second aspect of this invention.

[0018] A fourth aspect of the present invention provides a method for preparing a supported Rh catalyst, the method comprising:

[0019] (1) Preparation of phosphorus-modified support:

[0020] The phosphorus-containing modified support is prepared by applying the method described in the first aspect;

[0021] (2) The solution containing the Rh precursor is mixed with the phosphorus-modified support and the mixture is then subjected to drying II and calcination II in sequence.

[0022] The fifth aspect of the present invention provides a supported Rh catalyst prepared by the method described in the fourth aspect.

[0023] The sixth aspect of the present invention provides the application of the supported Rh catalyst described in the third and / or fifth aspects in the hydroformylation reaction of olefins.

[0024] A seventh aspect of the present invention provides a method for hydroformylation of olefins, the method comprising: introducing an olefin feedstock into a liquid-solid batch reactor containing a catalyst in the presence of syngas to carry out a hydroformylation reaction;

[0025] The catalyst is the supported Rh catalyst described in the third and / or fifth aspects.

[0026] The solution provided by this invention has the advantage of simple preparation method, and the obtained catalyst has the advantage of high catalytic activity, especially for the hydroformylation reaction of olefins. In addition, the catalyst of this invention has the characteristic of being easy to separate and recover from the liquid phase, and is suitable for industrial production.

[0027] The catalyst provided by this invention has Rh sites as its active sites, which are supported on the surface of a phosphorus-modified oxide support. The catalyst of this invention can be obtained via a two-step impregnation method, resulting in a simple preparation process.

[0028] In a preferred catalyst embodiment of the present invention, based on the mass of the support raw material in the phosphorus-modified support, the content of active metal rhodium is 0.1-1 wt%; and the content of phosphorus is 0.5-4.5 wt% (preferably 1-4 wt%).

[0029] The solution provided by this invention also has at least the following advantages:

[0030] 1. The method for preparing catalysts provided by the present invention can obtain the target catalyst through a simple excess impregnation-calcination process, without the need for reduction operation, resulting in low catalyst cost and no waste liquid generated during the preparation process.

[0031] 2. The catalyst provided by this invention has excellent catalytic activity and requires a low amount to be added to the reaction, with an olefin conversion rate of about 95%.

[0032] 3. Compared with existing catalysts for industrial homogeneous reaction processes, the catalyst prepared by this invention has significantly reduced the difficulty of catalyst separation, and is not sensitive to water and oxygen factors during storage and use. The reaction conditions are milder, showing superior potential for industrial application. Attached Figure Description

[0033] Figure 1 This is a STEM image of the catalyst prepared in Example 4 of the present invention. Detailed Implementation

[0034] The endpoints and any values ​​of the ranges disclosed herein are not limited to the precise ranges or values, and these ranges or values ​​should be understood to include values ​​close to these ranges or values. For numerical ranges, the endpoint values ​​of the various ranges, the endpoint values ​​of the various ranges and individual point values, and individual point values ​​can be combined with each other to obtain one or more new numerical ranges, which should be considered as specifically disclosed herein.

[0035] As mentioned above, the first aspect of the present invention provides a method for preparing a phosphorus-containing modified support, the method comprising: mixing and contacting a phosphorus-containing inorganic compound with a support raw material in the presence of a solvent, and then subjecting the contacted material to drying I and calcination I in sequence;

[0036] The phosphorus-containing inorganic compound is selected from at least one of phosphoric acid, diammonium dihydrogen phosphate, diammonium hydrogen phosphate, and ammonium phosphate;

[0037] The ratio of the mass of the phosphorus-containing inorganic compound to the mass of the carrier raw material, calculated as phosphorus element, is 0.5-4.5:100.

[0038] Preferably, the mixing contact is performed in the presence of ultrasound.

[0039] In a preferred embodiment, the conditions for ultrasound include: an ultrasound frequency of 20-60 kHz, a temperature of 20-40 °C, and a processing time of 0.5-2 h.

[0040] Preferably, the support material is selected from at least one of Al2O3, SiO2, ZrO2, TiO2, ZnO, and MgAl2O4. More preferably, the support material is selected from at least one of Al2O3, SiO2, ZrO2, and ZnO.

[0041] Preferably, the solvent is selected from at least one of water, methanol, ethanol, tetrahydrofuran, and dioxane.

[0042] In a preferred embodiment, the temperature of the drying process I is 80-100°C.

[0043] Preferably, the calcination temperature I is 450-700℃.

[0044] As previously stated, a second aspect of the present invention provides a phosphorus-containing modified carrier prepared by the method described in the first aspect.

[0045] Preferably, based on the mass of the carrier raw material in the phosphorus-containing modified carrier, the phosphorus content in the phosphorus-containing modified carrier is 0.5-4.5 wt%, more preferably 0.5-2 wt%.

[0046] As previously described, a third aspect of the present invention provides a supported Rh catalyst comprising a support and an active component supported on the support; wherein the active component comprises Rh.

[0047] The carrier is the phosphorus-containing modified carrier described in the second aspect of this invention.

[0048] Preferably, in the catalyst, the content of Rh, based on the mass of the support raw material in the phosphorus-modified support, is 0.01-1 wt%, more preferably 0.01-1 wt%, more preferably 0.02-0.7 wt%, particularly preferably 0.03-0.5 wt%, and even more preferably 0.05-0.5 wt%.

[0049] As previously described, a fourth aspect of the present invention provides a method for preparing a supported Rh catalyst, the method comprising:

[0050] (1) Preparation of phosphorus-modified support:

[0051] The phosphorus-containing modified support is prepared by applying the method described in the first aspect;

[0052] (2) The solution containing the Rh precursor is mixed with the phosphorus-modified support and the mixture is then subjected to drying II and calcination II in sequence.

[0053] Preferably, the mixing reaction is carried out in the presence of ultrasound; the ultrasound conditions for the mixing reaction include: an ultrasound frequency of 20-60 kHz, a temperature of 20-40 °C, and a processing time of 0.5-2 h.

[0054] In a preferred embodiment, the Rh precursor is selected from at least one of rhodium trichloride, rhodium nitrate, and rhodium acetate.

[0055] Preferably, the solvent in the solution containing the Rh precursor is selected from at least one of water, methanol, ethanol, tetrahydrofuran, and dioxane.

[0056] Preferably, in step (2), the ratio of the mass of the Rh precursor (calculated as rhodium) to the mass of the phosphorus-containing modified carrier (calculated as the mass of the carrier raw material contained therein) is 0.05-1:100.

[0057] Preferably, in step (2), the temperature of drying II is 80-100°C.

[0058] In a preferred embodiment, in step (2), the temperature of the calcination II is 270-480°C.

[0059] According to a particularly preferred embodiment, the method for preparing the supported Rh catalyst of the present invention includes:

[0060] a. Dissolve the phosphorus-containing inorganic compound in an appropriate amount of solvent to obtain a phosphorus precursor solution for the auxiliary agent;

[0061] b. The phosphorus precursor solution of the auxiliary agent is dropped onto the oxide carrier (i.e. the carrier raw material) to carry out the mixing contact, and the contacted material (solid-liquid mixture) is obtained;

[0062] c. Dry the material after contact I and calcine it in air atmosphere I to obtain the phosphorus-modified carrier (i.e., phosphorus-modified metal oxide carrier).

[0063] d. Dissolve the Rh-containing compound (i.e., the Rh precursor) in an appropriate amount of solvent to obtain a solution containing the Rh precursor;

[0064] e. The solution containing the Rh precursor is added dropwise onto the phosphorus-modified support to carry out the mixing reaction;

[0065] f. The mixed reaction material (solid-liquid mixture) is dried (II) and calcined in air atmosphere (II) to obtain the supported Rh catalyst.

[0066] As previously stated, the fifth aspect of the present invention provides a supported Rh catalyst prepared by the method described in the fourth aspect.

[0067] As previously stated, the sixth aspect of the present invention provides the application of the supported Rh catalyst described in the third and / or fifth aspects in the hydroformylation reaction of olefins.

[0068] As previously stated, a seventh aspect of the present invention provides a method for hydroformylation of olefins, the method comprising: introducing an olefin feedstock into a liquid-solid batch reactor containing a catalyst in the presence of syngas to carry out a hydroformylation reaction;

[0069] The catalyst is the supported Rh catalyst described in the third and / or fifth aspects.

[0070] The olefin hydroformylation method of the present invention can produce aldehydes from olefin feedstocks.

[0071] Preferably, the olefin feedstock is C6-C. 12 Branched or straight-chain olefins.

[0072] According to a preferred embodiment, the olefin feedstock is at least one selected from 1-hexene, 1-heptene, 1-octene, 2,4,4-trimethyl-1-pentene, 1-nonene, and 1-decene.

[0073] Preferably, the hydroformylation reaction of the present invention is carried out under a high-pressure mixed atmosphere of CO / H2.

[0074] Preferably, the synthesis gas contains CO and H2.

[0075] Preferably, the volume ratio of CO to H2 in the syngas is 1:0.5-2; more preferably, it is 1:0.6-1.5, and even more preferably, it is 1:1-1.2. The inventors have found that when the volume ratio of CO to H2 in the syngas is 1:1-1.2, the conversion rate of multi-branched high-carbon-number olefins can be significantly improved.

[0076] Preferably, the hydroformylation reaction is carried out at a temperature of 90-150°C for 4-12 hours.

[0077] More preferably, the reaction temperature of the hydroformylation reaction is 100-140°C, and more preferably 120-140°C.

[0078] Preferably, the total pressure of the synthesis gas is 2-8 MPa; more preferably, the total pressure of the synthesis gas is 4-5 MPa.

[0079] Preferably, the mass ratio of the catalyst to the olefin feedstock is 1:4-12.

[0080] Preferably, the hydroformylation reaction is carried out in the presence of an organic solvent selected from at least one of cyclohexane, toluene, methylcyclohexane, and xylene.

[0081] Unless otherwise specified, the present invention does not have any particular requirements for the specific operation of the ultrasonic step, and can use operations known in the art, such as adding the solution dropwise to another material with the assistance of a vortex oscillator, followed by ultrasonic treatment.

[0082] According to a particularly preferred embodiment, the method for hydroformylation of olefins of the present invention includes: introducing an olefin feedstock into a liquid-solid phase batch reactor containing a catalyst in the presence of an organic solvent; starting a stirrer and setting the stirring speed to 400-1000 rpm; increasing the pressure of the syngas (CO:H2 volume ratio preferably 1:1) to 1 MPa, then depressurizing it to 0.1 MPa, and repeating the process of adding syngas to 1 MPa. This operation is repeated 5 times to complete the air replacement in the reactor. Then, syngas is added to, for example, 1 MPa, and the temperature is raised to a preset reaction temperature. Syngas is then continuously added to a preset reaction pressure to start the hydroformylation reaction, with a reaction time of 4-12 hours.

[0083] The present invention will be described in detail below through examples. Unless otherwise specified, all raw materials used in the following examples of the present invention were obtained through commercial means.

[0084] Unless otherwise specified, in this invention, the term "room temperature" refers to 20°C-40°C.

[0085] The active components and additive contents of the catalysts below were obtained by inductively coupled atomic emission spectrometry (ICP-AES).

[0086] In the examples, the catalytic activity of the catalyst is expressed as the conversion rate of olefins and the selectivity of aldehydes and alcohols, and the calculation formula is as follows:

[0087] Olefin conversion rate = (1 - molar amount of olefin after reaction / initial molar amount of olefin) * 100%

[0088] Aldehyde selectivity = (Molar amount of aldehyde in the product) / (Initial molar amount of olefin - Molar amount of olefin after reaction) * 100%

[0089] Alcohol selectivity = (molar amount of alcohol in the product) / (initial molar amount of olefin - molar amount of olefin after reaction) * 100%

[0090] Example 1

[0091] The preparation of a phosphorus-modified support and a supported Rh catalyst, and its application in the hydroformylation reaction of olefins, are detailed in the following steps:

[0092] (1) Weigh 86.4 mg of (NH4)2HPO4 and dissolve it in 2 mL of deionized water to obtain a phosphorus precursor solution.

[0093] (2) With the aid of a vortex oscillator, the phosphorus precursor solution was added dropwise to 1.000 g of commercially available nano Al2O3 support (γ crystal phase, average particle size of 10 nm, purchased from Aladdin) for impregnation; then, the mixture was subjected to ultrasonic treatment (ultrasonic frequency of 40 kHz, temperature of 25 °C) for 0.5 h to make the support and precursor solution mixed evenly to obtain a solid-liquid mixture.

[0094] (3) The solid-liquid mixture obtained in (2) was placed in an oven at 100°C for drying for 12 hours, and then calcined at 500°C for 2 hours in an air atmosphere to obtain a phosphorus-modified metal oxide carrier.

[0095] (4) Dissolve 1.3 mg of RhCl3·3H2O in 1.6 mL of deionized water to obtain an active metal Rh precursor solution.

[0096] (5) With the assistance of a vortex oscillator, the active metal Rh precursor solution is dropped into the phosphorus-modified metal oxide carrier obtained in step (3) for impregnation. Then, the mixture is ultrasonically treated (ultrasonic frequency of 40KHz, temperature of 25℃) for 1h to make the carrier and precursor solution evenly mixed to obtain a solid-liquid mixture.

[0097] (6) The solid-liquid mixture obtained in (5) was placed in an oven at 100°C for drying for 12 hours, and then calcined at 450°C for 2 hours in an air atmosphere to obtain a supported Rh catalyst.

[0098] In this catalyst, based on the mass of the nano-Al2O3 support, the content of Rh is 0.1 wt% and the content of phosphorus is 2 wt%.

[0099] Example 2

[0100] The catalyst was prepared and its olefin hydroformylation activity was tested according to the steps in Example 1, except that:

[0101] In this embodiment, the amount of RhCl3·3H2O used in step (4) is 2.6 mg.

[0102] In the catalyst obtained in this embodiment, based on the mass of the nano-Al2O3 support, the content of Rh is 0.1 wt% and the content of phosphorus is 2 wt%.

[0103] Example 3

[0104] The catalyst was prepared and its olefin hydroformylation activity was tested according to the steps in Example 1, except that:

[0105] In this embodiment, the amount of RhCl3·3H2O used in step (4) is 7.8 mg.

[0106] In the catalyst obtained in this embodiment, based on the mass of the nano-Al2O3 support, the content of Rh is 0.3 wt% and the content of phosphorus is 2 wt%.

[0107] Example 4

[0108] The catalyst was prepared and its olefin hydroformylation activity was tested according to the steps in Example 1, except that:

[0109] In this embodiment, the amount of RhCl3·3H2O used in step (4) is 13mg.

[0110] In the catalyst obtained in this embodiment, based on the mass of the nano-Al2O3 support, the content of Rh is 0.5 wt% and the content of phosphorus is 2 wt%.

[0111] Example 5

[0112] The catalyst was prepared and its olefin hydroformylation activity was tested according to the steps in Example 1, except that:

[0113] In this embodiment, the amount of RhCl3·3H2O used in step (4) is 18.2 mg.

[0114] In the catalyst obtained in this embodiment, based on the mass of the nano-Al2O3 support, the content of Rh is 0.7 wt% and the content of phosphorus is 2 wt%.

[0115] Example 6

[0116] The catalyst was prepared and its olefin hydroformylation activity was tested according to the steps in Example 1, except that:

[0117] In this embodiment, the amount of (NH4)2HPO4 used in step (1) is 21.6 mg.

[0118] In the catalyst obtained in this embodiment, based on the mass of the nano-Al2O3 support, the content of Rh is 0.5 wt% and the content of phosphorus is 0.5 wt%.

[0119] Example 7

[0120] The catalyst was prepared and its olefin hydroformylation activity was tested according to the steps in Example 1, except that:

[0121] In this embodiment, the amount of (NH4)2HPO4 used in step (1) is 43.2 mg.

[0122] In the catalyst obtained in this embodiment, based on the mass of the nano-Al2O3 support, the content of Rh is 0.5 wt% and the content of phosphorus is 1 wt%.

[0123] Example 8

[0124] The catalyst was prepared and its olefin hydroformylation activity was tested according to the steps in Example 1, except that:

[0125] In this embodiment, the amount of (NH4)2HPO4 used in step (1) is 129.6 mg.

[0126] In the catalyst obtained in this embodiment, based on the mass of the nano-Al2O3 support, the content of Rh is 0.5 wt% and the content of phosphorus is 3 wt%.

[0127] Example 9

[0128] The catalyst was prepared and its olefin hydroformylation activity was tested according to the steps in Example 1, except that:

[0129] In this embodiment, the amount of (NH4)2HPO4 used in step (1) is 172.8 mg.

[0130] In the catalyst obtained in this embodiment, based on the mass of the nano-Al2O3 support, the content of Rh is 0.5 wt% and the content of phosphorus is 4 wt%.

[0131] Example 10

[0132] The catalyst was prepared and its olefin hydroformylation activity was tested according to the steps in Example 1, except that:

[0133] In this embodiment, the carrier material used in step (2) is commercially available nano-silica (Hydrophilic-300); the amount of RhCl3·3H2O used in step (4) is 13mg.

[0134] In the catalyst obtained in this embodiment, based on the mass of the nano-silica support, the content of Rh is 0.5 wt% and the content of phosphorus is 2 wt%.

[0135] Example 11

[0136] The catalyst was prepared and its olefin hydroformylation activity was tested according to the steps in Example 1, except that:

[0137] In this embodiment, the carrier material used in step (2) is commercially available nano zinc oxide (particle size range of 20nm-40nm); the amount of RhCl3·3H2O used in step (4) is 13mg.

[0138] In the catalyst obtained in this embodiment, based on the mass of the nano-zinc oxide support, the content of Rh is 0.5 wt% and the content of phosphorus is 2 wt%.

[0139] Example 12

[0140] The catalyst was prepared and its olefin hydroformylation activity was tested according to the steps in Example 1, except that:

[0141] In this embodiment, the carrier material used in step (2) is commercially available nano-zirconia (ZT-R10); the amount of RhCl3·3H2O used in step (4) is 13mg.

[0142] In the catalyst obtained in this embodiment, based on the mass of the nano-zirconia and the total weight of the phosphorus-modified metal oxide support therein, the content of Rh is 0.5 wt% and the content of phosphorus is 2 wt%.

[0143] Comparative Example 1

[0144] The catalyst was prepared and its olefin hydroformylation activity was tested according to the steps in Example 1, except that:

[0145] In this comparative example, steps (1), (2) and (3) are not performed. The amount of RhCl3·3H2O used in step (4) is 13 mg. In step (5), the active metal Rh precursor solution is directly added dropwise to the commercially available nano Al2O3 carrier (the source information is the same as in Example 1) for impregnation.

[0146] Everything else is the same as in Example 1.

[0147] Test Example 1

[0148] 500 mg of the prepared catalyst was added to a 100 mL high-pressure reactor. 25 mmol of the olefin feedstock 2,4,4-trimethyl-1-pentene and 30 mL of cyclohexane were added to the reactor. After sealing, 2 MPa of syngas (CO:H2 = 1:1) was introduced, followed by depressurization and gas replacement. This process was repeated three times. Then, 4 MPa of syngas (CO:H2 = 1:1) was introduced. The reactor was then heated to 120 °C and reacted for 8 h. After stopping the reaction, it was cooled to room temperature and depressurized. 600 μL of n-decane was added to the reaction solution as an internal standard, and a sample was taken. Analysis was performed using an Agilent 6890N chromatograph equipped with a DB-WAX capillary column. The catalyst types and their corresponding catalytic activity test results are shown in Table 1.

[0149] In the examples and comparative examples, the catalysts are denoted as a wt% Rh-b wt% P-MO. xWhere a and b represent the contents of Rh and P, respectively, and MO x It serves as an oxide support.

[0150] Table 1

[0151] Example Catalyst composition Conversion rate (%) Aldehyde selectivity (%) Alcohol selectivity (%) Example 1 <![CDATA[0.05wt%Rh-2wt%P-Al2O3]]> 80.2 81.3 4.1 Example 2 <![CDATA[0.1wt%Rh-2wt%P-Al2O3]]> 87.3 81.7 5.1 Example 3 <![CDATA[0.3wt%Rh-2wt%P-Al2O3]]> 95.4 83.4 5.0 Example 4 <![CDATA[0.5wt%Rh-2wt%P-Al2O3]]> 97.7 87.8 5.7 Example 5 <![CDATA[0.7wt%Rh-2wt%P-Al2O3]]> 97.2 86.9 5.3 Example 6 <![CDATA[0.5wt%Rh-0.5wt%P-Al2O3]]> 90.6 87.1 4.9 Example 7 <![CDATA[0.5wt%Rh-1wt%P-Al2O3]]> 93.5 87.9 5.9 Example 8 <![CDATA[0.5wt%Rh-3wt%P-Al2O3]]> 96.4 88.1 5.2 Example 9 <![CDATA[0.5wt%Rh-4wt%P-Al2O3]]> 86.4 86.4 5.6 Example 10 <![CDATA[0.5wt%Rh-2wt%P-SiO2]]> 95.4 84.1 4.9 Example 11 0.5wt% Rh-2wt% P-ZnO 96.8 85.3 6.2 Example 12 <![CDATA[0.5wt%Rh-2wt%P-ZrO2]]> 93.5 85.8 5.9 Comparative Example 1 <![CDATA[0.5wt%Rh-0wt%P-Al2O3]]> 82.7 85.2 4.8

[0152] Test Example 2

[0153] This test example was conducted using a similar method to Test Example 1, except that the olefin feedstock used in this test example was 1-hexene.

[0154] The types of catalysts and their corresponding catalytic activity test results are shown in Table 2.

[0155] Test Example 3

[0156] This test example was conducted using a similar method to Test Example 1, except that the olefin feedstock in this test example was 1-octene.

[0157] The types of catalysts and their corresponding catalytic activity test results are shown in Table 2.

[0158] Test Example 4

[0159] This test example was conducted using a method similar to that of Test Example 1, except that the olefin feedstock in this test example was 1-decene.

[0160] The types of catalysts and their corresponding catalytic activity test results are shown in Table 2.

[0161] Test Example 5

[0162] This test example was conducted using a method similar to that of Test Example 1, except that the olefin feedstock used in this test example was 1-dodecene.

[0163] The types of catalysts and their corresponding catalytic activity test results are shown in Table 2.

[0164] Table 2

[0165] Test case Catalyst source Conversion rate (%) Aldehyde selectivity (%) Alcohol selectivity (%) Test Example 2 Example 4 99.7 95.2 1.3 Test Example 3 Example 4 99.8 96.1 2.0 Test Example 4 Example 4 99.5 96.4 1.6 Test Example 5 Example 4 98.5 94.7 1.4

[0166] This invention provides, by way of example, a STEM image of the catalyst prepared in Example 4, from which... Figure 1 It was found that Rh has good dispersibility on the surface of phosphorus-modified oxide support, forming particles with a particle size range of 1nm-2nm. This is beneficial to improving the contact efficiency between active sites, CO, H2 and olefins, and improving the catalytic activity of the reaction.

[0167] Examples 1 to 5 and Comparative Example 1 of this invention illustrate the effect of rhodium content in the catalyst on catalyst performance. Table 1 shows that the Rh-based catalyst prepared in this invention exhibits high olefin conversion and selectivity for carbonylation products (aldehydes, alcohols) in the catalytic hydroformylation of heterogeneous olefins, with Rh playing a crucial role. The catalyst performance gradually improves with increasing Rh content. Based on the mass of the raw material support, the Rh mass fraction is preferably in the range of 0.5 wt% to 0.7 wt%. Further addition beyond this range does not significantly improve performance, which may be related to the dispersion of Rh on the catalyst surface. When the surface Rh loading increases to 0.5 wt% to 0.7 wt%, further addition of Rh at this point does not significantly increase the number of surface active sites due to the dispersion effect.

[0168] Examples 4, 6 to 9, and Comparative Example 1 of the present invention illustrate the effect of phosphorus content on catalyst performance. Table 1 shows that the introduction of phosphorus significantly promotes the catalytic activity of the supported Rh-based catalyst in the hydroformylation reaction of olefins. With the addition of phosphorus, the conversion rate gradually increases, while the selectivity of aldehyde and alcohol products remains essentially unchanged. Based on the mass of the feedstock support, the phosphorus mass fraction is preferably in the range of 1 wt% to 3 wt%. When the amount of phosphorus used further increases, the catalyst activity decreases. This may be because excessively high phosphorus content can lead to the formation of AlPO4 with Al2O3, affecting the dispersion of Rh on the surface and the contact between Rh and P or Al2O3.

[0169] The catalysts of Examples 4, 10 to 12 of this invention illustrate the effect of the type of support in the catalyst on the catalyst performance. As can be seen from Table 1, the catalysts formed by modifying different commonly used oxide supports with phosphorus and then supporting Rh all exhibit excellent olefin hydroformylation activity, indicating that the phosphorus modification strategy has good versatility.

[0170] As can be seen from Table 2 of this invention, the phosphorus-modified oxide-supported Rh catalyst prepared in this invention exhibits excellent substrate suitability for C6-C reactions. 12 It exhibits good catalytic activity in the hydroformylation of both straight-chain and branched-chain olefins.

[0171] The preferred embodiments of the present invention have been described in detail above; however, the present invention is not limited thereto. Within the scope of the inventive concept, various simple modifications can be made to the technical solutions of the present invention, including combinations of various technical features in any other suitable manner. These simple modifications and combinations should also be considered as the content disclosed in the present invention and are all within the protection scope of the present invention.

Claims

1. A method for preparing a phosphorus-modified support, characterized in that, The method includes: mixing and contacting a phosphorus-containing inorganic compound with a carrier raw material in the presence of a solvent, and then subjecting the contacted material to drying I and calcination I in sequence; The phosphorus-containing inorganic compound is selected from at least one of phosphoric acid, diammonium dihydrogen phosphate, diammonium hydrogen phosphate, and ammonium phosphate; The ratio of the mass of the phosphorus-containing inorganic compound to the mass of the carrier raw material, calculated as phosphorus element, is 0.5-4.5:

100.

2. The method according to claim 1, characterized in that, The mixing contact is performed in the presence of ultrasound; Preferably, the conditions for ultrasound include: an ultrasound frequency of 20-60 kHz, a temperature of 20-40°C, and a processing time of 0.5-2 h.

3. The method according to claim 1 or 2, characterized in that, The carrier material is selected from at least one of Al2O3, SiO2, ZrO2, TiO2, ZnO, and MgAl2O4.

4. The method according to any one of claims 1-3, characterized in that, The solvent is selected from at least one of water, methanol, ethanol, tetrahydrofuran, and dioxane.

5. The method according to any one of claims 1-4, characterized in that, The temperature of the drying process I is 80-100℃.

6. The method according to any one of claims 1-4, characterized in that, The calcination temperature is 450-700℃.

7. The phosphorus-containing modified support prepared by the method according to any one of claims 1-6; Preferably, based on the mass of the carrier raw material in the phosphorus-containing modified carrier, the phosphorus content in the phosphorus-containing modified carrier is 0.5-4.5 wt%, preferably 0.5-2 wt%.

8. A supported Rh catalyst, characterized in that, The catalyst contains a support and an active component supported on the support; the active component is composed of Rh. The carrier is the phosphorus-containing modified carrier as described in claim 7.

9. The supported Rh catalyst according to claim 8, characterized in that, In the catalyst, the content of Rh, calculated by element, is 0.01-1 wt%, preferably 0.03-0.5 wt%, based on the mass of the support raw material in the phosphorus-modified support.

10. A method for preparing a supported Rh catalyst, characterized in that, The method includes: (1) Preparation of phosphorus-modified support: The phosphorus-containing modified support is prepared by applying the method described in any one of claims 1-6; (2) The solution containing the Rh precursor is mixed with the phosphorus-modified support and the mixture is then subjected to drying II and calcination II in sequence.

11. The method according to claim 10, characterized in that, The mixing reaction is carried out in the presence of ultrasound; the ultrasound conditions for the mixing reaction include: ultrasound frequency of 20-60KHz, temperature of 20-40℃, and processing time of 0.5-2h.

12. The method according to claim 10 or 11, characterized in that, The Rh precursor is selected from at least one of rhodium trichloride, rhodium nitrate, and rhodium acetate; Preferably, in step (2), the ratio of the mass of the Rh precursor (calculated as rhodium) to the mass of the phosphorus-containing modified carrier (calculated as the mass of the carrier raw material contained therein) is 0.05-1:

100.

13. The method according to any one of claims 10-12, characterized in that, In step (2), the temperature of drying II is 80-100°C; Preferably, in step (2), the temperature of the calcination II is 270-480°C.

14. The supported Rh catalyst prepared by the method according to any one of claims 10-13.

15. The use of the supported Rh catalyst according to any one of claims 8, 9 and 14 in the hydroformylation of olefins.

16. A method for hydroformylation of an olefin, characterized in that, The method includes: introducing an olefin feedstock into a liquid-solid batch reactor containing a catalyst for hydroformylation in the presence of syngas; The catalyst is the supported Rh catalyst according to any one of claims 8, 9 and 14.

17. The method according to claim 16, characterized in that, The olefin feedstock is C6-C. 12 Branched or straight-chain olefins.

18. The method according to claim 16, characterized in that, The olefin raw material is at least one selected from 1-hexene, 1-heptene, 1-octene, 2,4,4-trimethyl-1-pentene, 1-nonene, and 1-decene.

19. The method according to any one of claims 16-18, characterized in that, The synthesis gas contains CO and H2; Preferably, the volume ratio of CO to H2 in the synthesis gas is 1:0.6-1.

5.

20. The method according to any one of claims 16-19, characterized in that, The hydroformylation reaction is carried out at a temperature of 90-150℃ for 4-12 hours. Preferably, the reaction temperature of the hydroformylation reaction is 100-130°C.

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