Bimetal catalyst as well as preparation method and application thereof in alkylol amine alkylation reaction

Abstract

The invention discloses a bimetallic catalyst as well as a preparation method and application thereof in an alkylol amine alkylation reaction, and relates to the technical field of metal catalysts, the bimetallic catalyst comprises a carrier and an active component loaded on the carrier; the active components comprise Ni and Cu; and in percentage by weight, the loading capacities of Ni and Cu are respectively 8-15% and 3-7% of the weight of the carrier. According to the preparation method, a femtosecond laser technology and a gradient pressure low-temperature freezing technology are combined to modify and activate aluminum oxide, so that the specific surface area of the aluminum oxide is effectively increased, and the pore channel structure is optimized. On the basis, a bimetallic catalyst is formed on the carrier by loading a proper amount of Ni and Cu active components, so that the selectivity and the yield of a target product tert-butylamine ethoxyethanol in an alkylol amine alkylation reaction taking diethylene glycol and tert-butylamine as raw materials are remarkably improved, and the catalyst shows a wide application prospect.

Description

Technical Field

[0001] The present invention relates to the technical field of metal catalysts, and particularly to a bimetallic catalyst, a preparation method thereof, and an application in the alcohol-amine alkylation reaction. Background Art

[0002] As an important reaction in the field of organic synthesis, the core of the alcohol-amine alkylation reaction is that an alcohol compound reacts with a nitrogen-containing compound (such as an amine) under the catalysis of a catalyst to undergo a nucleophilic substitution reaction, thereby introducing a carbon atom onto the nitrogen atom to form a C-N bond. Due to its unique chemical conversion method and wide applicability, this reaction process has shown great application value in many industrial fields such as petrochemical industry, fine chemical industry, and medicine, and has become an important means for synthesizing organic compounds with specific functions and structures.

[0003] The alcohol-amine alkylation reaction using diethylene glycol and tert-butylamine as raw materials to prepare tert-butylaminoethoxyethanol is a typical example. The tert-butylaminoethoxyethanol produced by this reaction is a compound with a wide range of uses. In the selective desulfurization process of refinery gas and natural gas, tert-butylaminoethoxyethanol can effectively selectively remove organic sulfur and improve the purity of the gas due to its unique chemical properties. At the same time, this compound is also used as a raw material for pharmaceutical intermediates and participates in the synthesis of compounds with specific pharmacological activities, providing an important chemical basis for the research and development of new drugs and having a wide range of uses.

[0004] However, despite the great application value of tert-butylaminoethoxyethanol, the current development status of the alcohol-amine alkylation reaction using diethylene glycol and tert-butylamine as raw materials to prepare this compound faces some challenges. Although various catalysts and methods have been used for this reaction, the selectivity and yield of the target product tert-butylaminoethoxyethanol are still not ideal enough. This limits the production efficiency and industrial application prospects of this compound. At the same time, in the research field of catalysts, as the skeleton and support of the catalyst, the properties of the carrier play a crucial role in the catalytic performance of the catalyst. However, unfortunately, in order to improve the selectivity and yield of tert-butylaminoethoxyethanol, the prior art often focuses on the improvement of the active components of the catalyst, while the research on the catalyst carrier is relatively weak. Summary of the Invention

[0005] To solve the above problems, the present invention provides a bimetallic catalyst, a preparation method thereof, and an application in the alcohol-amine alkylation reaction.

[0006] In a first aspect, the present invention provides a bimetallic catalyst, and the bimetallic catalyst includes a carrier and active components supported on the carrier;

[0007] The active components include Ni and Cu;

[0008] The loadings of the Ni and the Cu are 8-15% and 3-7% of the weight of the carrier, respectively, by weight percentage;

[0009] The preparation method of the carrier includes the following processes:

[0010] Step (1): Obtain alumina;

[0011] Step (2): Perform femtosecond laser activation treatment on the alumina to obtain first alumina;

[0012] Step (3): Perform freezing treatment on the first alumina in a gradient pressure and low temperature environment to obtain second alumina;

[0013] Step (4): Perform cyclic treatment on the second alumina in sequence according to the femtosecond laser activation treatment in step (2) and the freezing treatment in step (2) to obtain the carrier.

[0014] Further, the working condition parameters of the femtosecond laser activation treatment include: the femtosecond laser power is 0.8-1.7 W, the femtosecond laser scanning speed is 400-650 mm / s, the femtosecond laser scanning pitch is 20-30 μm, the femtosecond laser wavelength is 1000-1100 nm, the femtosecond laser pulse frequency is 100-200 kHz, the femtosecond laser pulse width is 100-200 fs, and the number of scans of the femtosecond laser is 1 time.

[0015] Further, the steps of the freezing treatment include the following processes:

[0016] The first stage: Perform freezing for 60-90 minutes under the conditions of a pressure of 10-15 Mpa and a temperature of -40 to -50 °C;

[0017] The second stage: Perform freezing for 60-90 minutes under the conditions of a pressure of 5-10 Mpa and a temperature of -40 to -50 °C;

[0018] The third stage: Restore to room temperature under normal pressure.

[0019] Further, the number of times of the cyclic treatment is 3-6 times.

[0020] Further, the loadings of the Ni and the Cu are 10% and 5% of the weight of the carrier, respectively, by weight percentage.

[0021] In a second aspect, based on the same inventive concept, the present invention provides a preparation method of a bimetallic catalyst according to any one of the first aspect, and the preparation method of the bimetallic catalyst includes the following steps:

[0022] Obtain a carrier;

[0023] The carrier is added to an impregnation solution containing nickel salt and copper salt, stirred and mixed, and then dried to obtain a first carrier;

[0024] The first carrier is calcined and then heated and reduced in a hydrogen / argon atmosphere to obtain the bimetallic catalyst.

[0025] Furthermore, the nickel salt includes at least one of nickel chloride and its hydrates, nickel acetate and its hydrates, and nickel nitrate and its hydrates; the copper salt includes at least one of copper chloride and its hydrates, copper acetate and its hydrates, and copper nitrate and its hydrates.

[0026] Furthermore, the working condition parameters of the calcination include: temperature is 500 - 600 °C, time is 4 - 7 hours; the working condition parameters of the heating reduction include: temperature is 550 - 750 °C, time is 2 - 4 hours.

[0027] In a third aspect, based on the same inventive concept, the present invention provides an application of the bimetallic catalyst described in any item of the first aspect or the bimetallic catalyst prepared by the preparation method described in any item of the second aspect in an alcohol amine alkylation reaction.

[0028] Furthermore, the type of the alcohol amine alkylation reaction includes preparing tert-butylaminoethoxyethanol using diethylene glycol and tert-butylamine as raw materials.

[0029] The above technical solutions provided by the embodiments of the present invention have at least the following advantages compared with the prior art:

[0030] The embodiments of the present invention provide a bimetallic catalyst, its preparation method, and its application in an alcohol amine alkylation reaction. The present invention uses a method combining femtosecond laser technology and gradient pressure cryogenic freezing technology to modify and activate alumina, effectively improving its specific surface area and optimizing the pore structure. On this basis, by loading appropriate amounts of Ni and Cu active components on the carrier to form a bimetallic catalyst, the selectivity and yield of the target product tert-butylaminoethoxyethanol in the alcohol amine alkylation reaction using diethylene glycol and tert-butylamine as raw materials are significantly improved, showing broad application prospects. BRIEF DESCRIPTION OF THE DRAWINGS

[0031] The drawings here are incorporated into the specification and constitute a part of this specification, showing embodiments in line with the present invention, and are used together with the specification to explain the principles of the present invention.

[0032] To more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the following will briefly introduce the drawings required for the description of the embodiments or the prior art. Obviously, for those of ordinary skill in the art, without creative efforts, other drawings can also be obtained based on these drawings.

[0033] Figure 1 It is a flowchart of the preparation method of the bimetallic catalyst provided by the present invention. Specific embodiments

[0034] To make the objectives, technical solutions, and advantages of the embodiments of the present invention clearer, the following will clearly and completely describe the technical solutions in the embodiments of the present invention with reference to the accompanying drawings in the embodiments of the present invention. Obviously, the described embodiments are some, but not all, of the embodiments of the present invention. All other embodiments obtained by those of ordinary skill in the art based on the embodiments of the present invention without creative efforts fall within the scope of protection of the present invention.

[0035] Unless otherwise specifically stated, various raw materials, reagents, instruments, and equipment used in the present invention can be obtained through market purchases or can be prepared by existing methods.

[0036] In a first aspect, the present invention provides a bimetallic catalyst, and the bimetallic catalyst includes a carrier and an active component supported on the carrier;

[0037] The active component includes Ni and Cu;

[0038] In terms of weight percentage, the loading amounts of Ni and Cu are 8-15% and 3-7% of the weight of the carrier, respectively;

[0039] The preparation method of the carrier includes the following processes:

[0040] Step (1): Obtain alumina;

[0041] Step (2): Perform femtosecond laser activation treatment on the alumina to obtain first alumina;

[0042] Step (3): Perform freezing treatment on the first alumina in a gradient pressure and low-temperature environment to obtain second alumina;

[0043] Step (4): Perform cyclic treatment on the second alumina in sequence according to the femtosecond laser activation treatment in step (2) and the freezing treatment in step (2) to obtain the carrier.

[0044] An embodiment of the present invention provides a bimetallic catalyst. The present invention combines femtosecond laser technology with gradient pressure low-temperature freezing technology to modify and activate alumina, effectively improving its specific surface area and optimizing the pore structure. On this basis, by loading appropriate amounts of Ni and Cu active components onto the carrier to form a bimetallic catalyst, the selectivity and yield of the target product tert-butylaminoethoxyethanol in the alcohol-amine alkylation reaction using diethylene glycol and tert-butylamine as raw materials are significantly improved, showing broad application prospects.

[0045] In some specific embodiments, the alumina in the present invention can directly use commercially available products or be prepared by itself according to the preparation process disclosed in the prior art. For example, the following method can be used: Weigh 100 g of commercial pseudo-boehmite dry gel powder (dry basis content 71.5 wt%), add 2.1 g of sesbania powder and 4.2 g of boric acid, mix evenly to obtain a first mixture; dissolve 3.6 g of acetic acid in 86 g of deionized water, add it to the first mixture, knead and extrude it into a clover shape with a diameter of 3.0 mm on a single-screw extruder; then dry it at 100 °C for 5 hours and calcine it at 750 °C for 4 hours to obtain alumina.

[0046] In some specific embodiments, the working condition parameters of the femtosecond laser activation treatment include: the femtosecond laser power is 0.8 - 1.7 W, the femtosecond laser scanning speed is 400 - 650 mm / s, the femtosecond laser scanning spacing is 20 - 30 μm, the femtosecond laser wavelength is 1000 - 1100 nm, the femtosecond laser pulse frequency is 100 - 200 kHz, the femtosecond laser pulse width is 100 - 200 fs, and the number of scans of the femtosecond laser is 1 time; preferably, the working condition parameters of the femtosecond laser activation treatment include: the femtosecond laser power is 1.2 W, the femtosecond laser scanning speed is 500 mm / s, the femtosecond laser scanning spacing is 25 μm, the femtosecond laser wavelength is 1050 nm, the femtosecond laser pulse frequency is 160 kHz, the femtosecond laser pulse width is 140 fs, and the number of scans of the femtosecond laser is 1 time.

[0047] In some specific embodiments, the steps of the freezing treatment include the following process:

[0048] The first stage: Freeze for 60 - 90 minutes under the conditions of a pressure of 10 - 15 Mpa and a temperature of -40 - -50 °C; preferably freeze for 70 minutes under the conditions of a pressure of 12 Mpa and a temperature of -45 °C;

[0049] The second stage: Freeze for 60 - 90 minutes under the conditions of a pressure of 5 - 10 Mpa and a temperature of -40 - -50 °C; preferably freeze for 70 minutes under the conditions of a pressure of 8 Mpa and a temperature of -45 °C;

[0050] The third stage: Return to room temperature under normal pressure.

[0051] In some specific embodiments, the number of times of the cyclic treatment is 3 to 6 times.

[0052] In some specific embodiments, in terms of weight percentage, the loadings of the Ni and the Cu are 10% and 5% of the weight of the carrier, respectively.

[0053] Second aspect, based on the same inventive concept, the present invention provides a preparation method of a bimetallic catalyst according to any one of the first aspect, as Figure 1 shown, the preparation method of the bimetallic catalyst comprises the following steps:

[0054] Obtain a carrier;

[0055] Add the carrier into an impregnation solution containing nickel salt and copper salt, stir and mix, and then dry to obtain a first carrier;

[0056] Calcine the first carrier, and then carry out heating reduction in a hydrogen / argon atmosphere to obtain the bimetallic catalyst.

[0057] The preparation method of the bimetallic catalyst provided by the present invention adopts an impregnation-calcination-reduction method, which is simple in operation, does not require additional specific equipment, and is suitable for industrial production.

[0058] In some specific embodiments, the nickel salt includes at least one of nickel chloride and its hydrates, nickel acetate and its hydrates, and nickel nitrate and its hydrates; the copper salt includes at least one of copper chloride and its hydrates, copper acetate and its hydrates, and copper nitrate and its hydrates.

[0059] In some specific embodiments, the working condition parameters of the calcination include: temperature is 500 - 600 °C, time is 4 - 7 hours; the working condition parameters of the heating reduction include: temperature is 550 - 750 °C, time is 2 - 4 hours.

[0060] Third aspect, based on the same inventive concept, the present invention provides an application of a bimetallic catalyst according to any one of the first aspect or a bimetallic catalyst prepared by using the preparation method of the bimetallic catalyst according to any one of the second aspect in an alcohol amine alkylation reaction.

[0061] The bimetallic catalyst provided by the present invention can significantly improve the yield and selectivity of the target product, and has a wide range of uses.

[0062] In some specific embodiments, the type of the alcohol amine alkylation reaction includes preparing tert-butylaminoethoxyethanol by using diethylene glycol and tert-butylamine as raw materials.

[0063] It should be noted that for the component raw materials involved in the bimetallic catalyst, its preparation method, and its application in the alkanolamine alkylation reaction provided by the embodiments of the present invention, unless otherwise specifically defined or described, commercially available products can be directly used, or they can be prepared by oneself using existing publicly disclosed preparation methods. At the same time, for the steps and parameters involved, unless otherwise specifically defined or described, they can be carried out according to the preparation processes disclosed in the prior art or directly used with reference to the operating instructions of existing equipment, and will not be elaborated one by one in this invention document.

[0064] The present invention will be further described below in conjunction with specific embodiments. It should be understood that these embodiments are only used to illustrate the present invention and not to limit the scope of the present invention. The experimental methods without specific conditions noted in the following embodiments are generally determined according to national standards. If there are no corresponding national standards, they are carried out according to general international standards, conventional conditions, or the conditions recommended by the manufacturer.

[0065] Example 1

[0066] This example provides a support, and the preparation method of the support includes the following steps:

[0067] Step (1): Weigh 100 g of pseudo-boehmite dry gel powder, add 2.1 g of sesbania powder and 4.2 g of boric acid, mix evenly to obtain a first mixture; dissolve 3.6 g of acetic acid in 86 g of deionized water, add it to the first mixture, knead and extrude it into a three-leaf shape with a diameter of 3.0 mm on a single-screw extruder; then dry it at 100 °C for 5 hours and calcine it at 750 °C for 4 hours to obtain alumina.

[0068] Step (2): Perform femtosecond laser activation treatment on the alumina. The femtosecond laser power is 1.2 W, the femtosecond laser scanning speed is 500 mm / s, the femtosecond laser scanning spacing is 25 μm, the femtosecond laser wavelength is 1050 nm, the femtosecond laser pulse frequency is 160 kHz, the femtosecond laser pulse width is 140 fs, and the number of femtosecond laser scans is 1 time to obtain a first alumina.

[0069] Step (3): Freeze the first alumina in a gradient pressure and low-temperature environment to obtain a second alumina. Among them, the freezing treatment includes the following process: freeze it for 70 minutes under the conditions of a pressure of 12 Mpa and a temperature of -45 °C, then freeze it for 70 minutes under the conditions of a pressure of 8 Mpa and a temperature of -45 °C, and finally restore it to room temperature under normal pressure.

[0070] Step (4): Perform cyclic treatment on the second alumina 5 times in sequence according to the femtosecond laser activation treatment in step (2) and the freezing treatment in step (2) (that is, the femtosecond laser activation treatment in step (2) and the freezing treatment in step (2) are each carried out 5 times) to obtain the support.

[0071] Example 2

[0072] This example provides a carrier and a preparation method thereof. The difference from Example 1 is only as follows: 1) In step (2), the working condition parameters of the femtosecond laser activation treatment are adjusted to: the femtosecond laser power is 0.8 W, the femtosecond laser scanning speed is 400 mm / s, the femtosecond laser scanning pitch is 20 μm, the femtosecond laser wavelength is 1000 nm, the femtosecond laser pulse frequency is 100 kHz, the femtosecond laser pulse width is 100 fs, and the number of femtosecond laser scans is 1 time; 2) In step (3), the freezing treatment is adjusted to: freeze for 60 minutes under the conditions of a pressure of 10 Mpa and a temperature of -50 °C, then freeze for 60 minutes under the conditions of a pressure of 5 Mpa and a temperature of -50 °C, and finally restore to room temperature under normal pressure; 3) In step (4), the number of cycle treatments is adjusted to 6 times.

[0073] Example 3

[0074] This example provides a carrier and a preparation method thereof. The difference from Example 1 is only as follows: 1) In step (2), the working condition parameters of the femtosecond laser activation treatment are adjusted to: the femtosecond laser power is 1.7 W, the femtosecond laser scanning speed is 650 mm / s, the femtosecond laser scanning pitch is 30 μm, the femtosecond laser wavelength is 1100 nm, the femtosecond laser pulse frequency is 200 kHz, the femtosecond laser pulse width is 200 fs, and the number of femtosecond laser scans is 1 time; 2) In step (3), the freezing treatment is adjusted to: freeze for 90 minutes under the conditions of a pressure of 15 Mpa and a temperature of -45 °C, then freeze for 90 minutes under the conditions of a pressure of 10 Mpa and a temperature of -45 °C, and finally restore to room temperature under normal pressure; 3) In step (4), the number of cycle treatments is adjusted to 3 times.

[0075] Example 4

[0076] This example provides a bimetallic catalyst. The bimetallic catalyst includes a carrier and an active component supported on the carrier; the active component includes Ni and Cu; in terms of weight percentage, the loading amounts of Ni and Cu are 10% and 5% of the weight of the carrier respectively; the carrier is the carrier obtained in Example 1.

[0077] The preparation method of the above bimetallic catalyst includes the following steps:

[0078] Weigh 0.426 g of nickel acetate tetrahydrate and 0.157 g of copper acetate monohydrate, dissolve them in 50 mL of deionized water, and stir well for 30 min to obtain an impregnation solution containing nickel salt and copper salt;

[0079] Weigh 1 g of the carrier obtained in Example 1 and add it to the impregnation solution. Continuously stir at room temperature for 2 h, and then use a temperature-controlled magnetic stirrer to heat and evaporate the excess water at 90 °C; collect the solid sample and dry it overnight in an oven at 100 °C to obtain the first carrier;

[0080] Lay the first carrier flat in a porcelain boat and calcine it in a muffle furnace at 550 °C at a heating rate of 3 °C·min -1 for 5 h; then place it in a tubular furnace in an atmosphere of 10% H 2 / Ar (gas flow rate 100 mL·min -1 ) and reduce it at 600 °C for 3 h to obtain the bimetallic catalyst.

[0081] Example 5

[0082] This example provides a bimetallic catalyst, which includes a carrier and active components supported on the carrier; the active components include Ni and Cu; in terms of weight percentage, the loading amounts of Ni and Cu are 15% and 7% of the weight of the carrier respectively; the carrier is the carrier obtained in Example 2.

[0083] The preparation method of the above bimetallic catalyst is the same as that of Example 4.

[0084] Example 6

[0085] This example provides a bimetallic catalyst, which includes a carrier and active components supported on the carrier; the active components include Ni and Cu; in terms of weight percentage, the loading amounts of Ni and Cu are 8% and 3% of the weight of the carrier respectively; the carrier is the carrier obtained in Example 3.

[0086] The preparation method of the above bimetallic catalyst is the same as that of Example 4.

[0087] Comparative Example 1

[0088] This example provides a carrier and its preparation method, which is only different from Example 1 in that: the freezing treatment in step (3) of Example 1 is not carried out.

[0089] The preparation method of the above carrier includes the following steps:

[0090] Step (1): Weigh 100 g of pseudo-boehmite dry gel powder, add 2.1 g of sesbania powder and 4.2 g of boric acid, mix evenly to obtain a first mixture; dissolve 3.6 g of acetic acid in 86 g of deionized water, add it to the first mixture, knead and extrude it into a three-leaf shape with a diameter of 3.0 mm on a single-screw extruder; then dry it at 100 °C for 5 hours and calcine it at 750 °C for 4 hours to obtain alumina;

[0091] Step (2): Subject the alumina to femtosecond laser activation treatment. The femtosecond laser power is 1.2 W, the femtosecond laser scanning speed is 500 mm / s, the femtosecond laser scanning pitch is 25 μm, the femtosecond laser wavelength is 1050 nm, the femtosecond laser pulse frequency is 160 kHz, the femtosecond laser pulse width is 140 fs, the number of femtosecond laser scans is 1 time. Repeat the above femtosecond laser activation treatment 5 times to obtain the support.

[0092] Comparative Example 2

[0093] This example provides a support and its preparation method, which is only different from Example 1 in that: the femtosecond laser activation treatment in step (2) of Example 1 is not carried out.

[0094] The preparation method of the above support includes the following steps:

[0095] Step (1): Weigh 100 g of pseudo-boehmite dry gel powder, add 2.1 g of sesbania powder and 4.2 g of boric acid, mix evenly to obtain the first mixture; dissolve 3.6 g of acetic acid in 86 g of deionized water, add it to the first mixture, knead and extrude it into a clover shape with a diameter of 3.0 mm on a single-screw extruder; then dry at 100 °C for 5 hours, and then calcine at 750 °C for 4 hours to obtain alumina;

[0096] Step (2): Subject the alumina to freezing treatment under a gradient pressure and low-temperature environment. Repeat the above freezing treatment 5 times to obtain the support; wherein, the freezing treatment includes the following process: freeze at a pressure of 12 Mpa and a temperature of -45 °C for 70 minutes, then freeze at a pressure of 8 Mpa and a temperature of -45 °C for 70 minutes, and finally restore to room temperature under normal pressure.

[0097] Comparative Example 3

[0098] This example provides a support and its preparation method, which is only different from Example 1 in that: the freezing treatment in step (3) of Example 1 is adjusted to: freeze at normal pressure and a temperature of -45 °C for 140 minutes, and finally restore to room temperature under normal pressure.

[0099] Test Example 1

[0100] In this example, the specific surface area and pore size distribution of the supports obtained in Examples 1 to 3 and Comparative Examples 1 to 3, and unmodified alumina (i.e., the alumina obtained by using step (1) in Example 1) were measured, and the test results are shown in Table 1.

[0101] Table 1

[0102]

[0103]

[0104] As can be seen from Table 1, compared with Comparative Examples 1-3 and unmodified alumina, the specific surface area of the support obtained by the method combining femtosecond laser technology and gradient pressure low-temperature freezing technology in the present invention is larger, and the proportion of the pore distribution of 20-30 nm is significantly increased, effectively improving its specific surface area and optimizing the pore structure.

[0105] Test Example 2

[0106] In this example, the catalytic performance of the bimetallic catalysts obtained in Examples 4-6 for the preparation of tert-butylaminoethoxyethanol from diethylene glycol and tert-butylamine was investigated.

[0107] Test method: Add a bimetallic catalyst (0.026 g), diethylene glycol (0.848 g), and tert-butylamine (1.752 g) to the reaction kettle. After sealing, purge with H 2 for 3 times to remove the air in the reaction kettle, and then fill with 0.5 MPa H 2 , the stirring speed of the magnetic stirrer is 600 rpm, and keep the temperature at 220 °C for 7 h after reaching the set temperature. After the reaction is completed, cool to room temperature, discharge the gas in the kettle, filter the catalyst, and collect the product. By gas phase analysis, the selectivity and yield of the target product tert-butylaminoethoxyethanol are shown in Table 2.

[0108] Table 2

[0109]

[0110] As can be seen from Table 2, the bimetallic catalysts provided by the examples of the present invention have excellent catalytic performance for the preparation of tert-butylaminoethoxyethanol from diethylene glycol and tert-butylamine, and the selectivity and yield of the target product can reach up to 90.6% and 85.2% respectively at most.

[0111] In summary, the examples of the present invention provide a bimetallic catalyst, its preparation method and application in the alcohol-amine alkylation reaction. The present invention uses a method combining femtosecond laser technology and gradient pressure low-temperature freezing technology to modify and activate alumina, effectively improving its specific surface area and optimizing the pore structure. On this basis, by loading appropriate amounts of Ni and Cu active components on the support to form a bimetallic catalyst, the selectivity and yield of the target product tert-butylaminoethoxyethanol in the alcohol-amine alkylation reaction using diethylene glycol and tert-butylamine as raw materials are significantly improved, showing broad application prospects.

[0112] Various embodiments of the present invention may exist in the form of a range; it should be understood that the description in the form of a range is only for convenience and brevity and should not be construed as a rigid limitation on the scope of the present invention; therefore, it should be considered that the described range description has specifically disclosed all possible sub-ranges and individual values within that range. For example, it should be considered that the range description from 1 to 6 has specifically disclosed sub-ranges such as from 1 to 3, from 1 to 4, from 1 to 5, from 2 to 4, from 2 to 6, from 3 to 6, etc., and individual numbers within the range, such as 1, 2, 3, 4, 5, and 6, and this applies regardless of the range. Additionally, whenever a numerical range is indicated herein, it means including any cited number (fraction or integer) within the indicated range.

[0113] The above are only specific embodiments of the present invention, enabling those skilled in the art to understand or implement the present invention. Various modifications to these embodiments will be obvious to those skilled in the art, and the general principles defined herein can be implemented in other embodiments without departing from the spirit or scope of the present invention. Therefore, the present invention will not be limited to these embodiments shown herein, but rather to the broadest scope consistent with the principles and novel features claimed herein.

Claims

1. A bimetallic catalyst, characterized in that: The bimetallic catalyst comprises a carrier and an active component supported on the carrier; The active components include Ni and Cu; In terms of weight percentage, the loading amounts of Ni and Cu are 8-15% and 3-7% of the weight of the carrier, respectively; The preparation method of the carrier comprises the following steps: Step (1): obtaining aluminum oxide; Step (2): subjecting the aluminum oxide to femtosecond laser activation treatment to obtain a first aluminum oxide; Step (3): freezing the first aluminum oxide in a gradient pressure low temperature environment to obtain a second aluminum oxide; Step (4): The second alumina is subjected to a cyclic treatment in sequence according to the femtosecond laser activation treatment in step (2) and the freezing treatment in step (2) to obtain the carrier.

2. The bimetallic catalyst according to claim 1, characterized in that The working condition parameters of the femtosecond laser activation treatment include: femtosecond laser power of 0.8 to 1.7 W, femtosecond laser scanning speed of 400 to 650 mm / s, femtosecond laser scanning spacing of 20 to 30 μm, femtosecond laser wavelength of 1000 to 1100 nm, femtosecond laser pulse frequency of 100 to 200 kHz, femtosecond laser pulse width of 100 to 200 fs, and the number of femtosecond laser scans is 1 time.

3. The bimetallic catalyst according to claim 1, characterized in that The freezing process comprises the following steps: The first stage: freezing for 60 to 90 minutes at a pressure of 10 to 15 MPa and a temperature of -40 to -50°C; The second stage: freezing for 60 to 90 minutes at a pressure of 5 to 10 MPa and a temperature of -40 to -50°C; The third stage: return to room temperature under normal pressure.

4. The bimetallic catalyst according to claim 1, characterized in that The number of the cyclic treatment is 3 to 6 times.

5. The bimetallic catalyst according to claim 1, characterized in that In terms of weight percentage, the loading amounts of Ni and Cu are 10% and 5% of the weight of the carrier, respectively.

6. A method for preparing a bimetallic catalyst according to any one of claims 1 to 5, characterized in that: The preparation method of the bimetallic catalyst comprises the following steps: obtaining a vector; Adding the carrier to an impregnation solution containing nickel salt and copper salt, stirring and mixing, and then drying to obtain a first carrier; The first carrier is calcined and then heated and reduced in a hydrogen / argon atmosphere to obtain the bimetallic catalyst.

7. The method for preparing a bimetallic catalyst according to claim 6, characterized in that: The nickel salt includes at least one of nickel chloride and its hydrate, nickel acetate and its hydrate, and nickel nitrate and its hydrate; the copper salt includes at least one of copper chloride and its hydrate, copper acetate and its hydrate, and copper nitrate and its hydrate.

8. The method for preparing a bimetallic catalyst according to claim 6, characterized in that: The working condition parameters of the calcination include: a temperature of 500-600° C. and a time of 4-7 hours; the working condition parameters of the heating reduction include: a temperature of 550-750° C. and a time of 2-4 hours.

9. Use of a bimetallic catalyst as claimed in any one of claims 1 to 5 or a bimetallic catalyst prepared by the preparation method of the bimetallic catalyst as claimed in any one of claims 7 to 8 in an alkylation reaction of alcoholamines.

10. The use according to claim 9, characterized in that: The type of alcoholamine alkylation reaction includes preparing tert-butylaminoethoxyethanol using diethylene glycol and tert-butylamine as raw materials.

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