A normalisation catalyst, its preparation and use

Abstract

The application discloses a normal-conversion catalyst and a preparation method and application thereof, and the preparation method comprises the following steps: (1) molecular sieve surface treatment: treating the molecular sieve in a plasma atmosphere; (2) active component loading: uniformly mixing a precursor solution containing an active component with the material obtained in the step (1), and then performing aging treatment; (3) crystallization treatment: uniformly mixing the material obtained in the step (2), water and a template agent, and then performing crystallization treatment, and then performing washing, drying and heat treatment to obtain the normal-conversion catalyst. The catalyst has good anti-carbon deposition performance, good stability, and the catalyst preparation method is simple and easy to implement.

Description

Technical Field

[0001] This invention relates to a catalytic material and its preparation method, specifically to an ortho-catalyst, its preparation method, and its application. Background Technology

[0002] n-Butane is a common hydrocarbon substance, a colorless and easily liquefied gas at room temperature and pressure. As an important chemical raw material, n-butane can be used directly as fuel, and can also be used as a solvent and refrigerant in subcritical biotechnology extraction. In addition, butane can be used to produce butene, butadiene, maleic anhydride, acetic acid, acetaldehyde, halobutane, nitrobutane and other chemicals in the presence of a catalyst.

[0003] Currently, the main method for producing n-butane in my country involves the physical separation and purification of mixed C4 components from refinery gas and cracked gas generated during natural gas and petroleum refining processes. However, this method inevitably produces large amounts of byproducts such as isobutane, significantly increasing storage and transportation costs for enterprises and severely impacting their economic efficiency. Therefore, developing a more economical and efficient method for producing n-butane is of great significance. Among these methods, the preparation of high-purity n-butane through an ortho-configuration reaction of isobutane under the action of a catalyst has become a research hotspot.

[0004] CN104892339A proposes a method for producing n-butane from isobutane via hydrogenation. The isobutane is first converted to n-butane in a normalization reactor, then fed into a hydrogenation saturation reactor to remove the olefins generated during the normalization reaction. After separation, pure n-butane is obtained. The isobutane normalization reaction is carried out on a conventional metal chloride catalyst at 500°C and 3.0 MPa to produce n-butane.

[0005] CN108530254A proposes a method for preparing n-butane from mixed C4 components. The mixed C4 components are desulfurized and then separated in an extraction tower. n-Butane is separated from the bottom of the tower, while isobutane is collected in the middle. The collected isobutane is then subjected to an n-butane reaction in the presence of a catalyst to produce n-butane. Isobutane n-butane n-butane reaction involves one or more metal-supported chlorine-containing catalysts, with reaction temperatures >400℃ and pressures >2.5MPa, resulting in problems such as equipment corrosion, environmental pollution, and high energy consumption.

[0006] In the aforementioned patents, the normalization catalyst is a traditional metal chlorine oxide catalyst or a chlorine-containing catalyst supported by one or more metals, and the catalyst performance needs to be further improved. Summary of the Invention

[0007] To address the shortcomings of existing technologies, this invention provides an ortho-catalyst, its preparation method, and its application. The catalyst exhibits good resistance to carbon deposition, high stability, and its preparation method is simple and easy to implement.

[0008] The first aspect of this invention provides a method for preparing an ortho-catalyst, the method comprising the following steps:

[0009] (1) Surface treatment of molecular sieves: The molecular sieves are treated in a plasma atmosphere;

[0010] (2) Loading of active components: The precursor solution containing active components is mixed evenly with the material obtained in step (1), and then aged.

[0011] (3) Crystallization treatment: The material obtained in step (2), water and template agent are mixed evenly and crystallized. Then, after washing, drying and heat treatment, the ortho-formation catalyst is obtained.

[0012] Furthermore, in the above-mentioned method for preparing the ortho-formation catalyst, the molecular sieve in step (1) can be selected from one or more of ZSM-22 molecular sieve, ZSM-5 molecular sieve, and Y molecular sieve, preferably ZSM-22 molecular sieve.

[0013] Furthermore, in the above-mentioned method for preparing the ortho-catalyst, the plasma in step (1) is one or more of dielectric barrier discharge plasma, sliding arc discharge plasma, and glow discharge plasma, preferably dielectric barrier discharge plasma.

[0014] Furthermore, in the above-mentioned method for preparing the ortho-catalyst, the plasma atmosphere in step (1) is derived from an inert gas or a mixture of an inert gas and oxygen, wherein the volume percentage of oxygen in the mixture is 20%-70%, preferably 30%-50%; the inert gas is at least one of argon, helium, and nitrogen, preferably argon.

[0015] Furthermore, in the above-mentioned method for preparing the ortho-catalyst, the specific operation process of the treatment under a plasma atmosphere in step (1) is as follows: the molecular sieve is placed in a plasma reactor and treated in an inert gas or a mixture of inert gas and oxygen at a temperature of 250℃-500℃, preferably 250℃-450℃, for 0.5 h-5 h, preferably 0.5 h-3 h; the volume flow rate of the inert gas or the mixture of inert gas and oxygen is 20 mL / min-150 mL / min, preferably 35 mL / min-100 mL / min.

[0016] Furthermore, in the above-mentioned method for preparing the ortho-catalyst, the molecular sieve in step (1) is treated in a plasma atmosphere in two stages. After the molecular sieve is treated in a plasma atmosphere, the resulting material is then treated in a plasma atmosphere in a second stage. The temperature of the first stage treatment is 250℃-350℃, preferably 250℃-300℃, and the treatment time is 0.5 h-3 h, preferably 0.5 h-1 h. The atmosphere of the first stage treatment is preferably argon. The temperature of the second stage treatment is 25℃-250℃ higher than that of the first stage treatment, preferably 50℃-200℃ higher. The treatment time of the second stage treatment is 0.5 h-3 h longer than that of the first stage treatment, preferably 1 h-2 h longer. The atmosphere of the second stage treatment is preferably a mixture of inert gas and oxygen.

[0017] Furthermore, in the above-mentioned method for preparing the ortho-catalyst, the active component in step (2) is Pt and / or Pd, preferably Pt; the precursor solution containing the active component is one or more of the aqueous solutions of chloroplatinic acid, platinum nitrate, dichlorotetraammineplatinum, palladium acetate, palladium chloride, palladium nitrate, sodium chloropalladium, potassium chloropalladium, and dichlorotetraammineplatinum, preferably an aqueous solution of platinum nitrate or dichlorotetraammineplatinum.

[0018] Furthermore, in the above-mentioned method for preparing the ortho-catalyst, the mass ratio of the material obtained in step (1) to the precursor containing the active component in step (2) is (20-150):1, preferably (30-100):1.

[0019] Furthermore, in the above-mentioned method for preparing the ortho-catalyst, the mixing in step (2) can be carried out by impregnation. The impregnation process can be one-step impregnation or multi-step impregnation, preferably multi-step impregnation.

[0020] Furthermore, in the above-mentioned method for preparing the ortho-catalyst, the aging time in step (2) is 2 h - 24 h, preferably 6 h - 10 h, and the aging temperature is 30℃ - 100℃, preferably 40℃ - 80℃.

[0021] Furthermore, in the above-mentioned method for preparing the ortho-catalyst, an auxiliary agent may be introduced in step (3). Specifically, the introduction process may involve mixing the auxiliary agent with the material obtained in step (2), water, and template agent, and then performing crystallization treatment. The auxiliary agent is one or more of urea, ammonium oxalate, ammonium carbonate, and ammonium bicarbonate, preferably urea and / or ammonium bicarbonate. The molar ratio of the material obtained in step (2) to the auxiliary agent is 1:(0.1~6), preferably 1:(0.5~3).

[0022] Furthermore, in the above-mentioned method for preparing the ortho-catalyst, the template agent in step (3) is one or more of tetrapropylammonium hydroxide, tetrapropylammonium bromide, tetrabutylammonium bromide, tetraethylammonium hydroxide, and triethylamine, preferably tetrapropylammonium hydroxide.

[0023] Furthermore, in the above-mentioned method for preparing the ortho-catalyst, the molar ratio of the material, water and template agent obtained in step (2) of step (3) is 1:(20~100):(0.05~4), preferably 1:(30~60):(0.1~2).

[0024] Furthermore, in the above-mentioned method for preparing the ortho-catalyst, the crystallization conditions in step (3) are as follows: the crystallization time is 12 h - 48 h, preferably 12 h - 36 h; the crystallization temperature is 130℃ - 250℃, preferably 150℃ - 200℃.

[0025] Furthermore, in the above-mentioned method for preparing the ortho-catalyst, the drying temperature in step (3) is 80℃-200℃, preferably 80℃-120℃; the drying time is 6 h-48 h, preferably 6 h-36 h, and more preferably 6 h-24 h.

[0026] Furthermore, in the above-mentioned method for preparing the ortho-catalyst, the heat treatment in step (3) can be calcination treatment and / or plasma treatment, preferably plasma treatment.

[0027] Furthermore, in the above-mentioned method for preparing the ortho-catalyst, when the heat treatment in step (3) is calcination, the calcination temperature is 400℃-600℃, preferably 450℃-550℃; the treatment time is 2h-6h, preferably 2h-5h, and more preferably 3h-4h.

[0028] Furthermore, in the above-mentioned method for preparing the ortho-catalyst, when the heat treatment in step (3) is plasma treatment, the specific operation process of plasma treatment is as follows: the material obtained by drying in step (3) is placed in a plasma reactor and treated at 350℃-400℃ for 1 h-3 h, preferably 1 h-2 h, in an inert atmosphere with a flow rate of 25 mL / min-60 mL / min, preferably 35 mL / min-50 mL / min.

[0029] Furthermore, in the above-mentioned method for preparing the ortho-catalyst, the plasma used in the plasma reactor is at least one of dielectric barrier discharge plasma, sliding arc discharge plasma, and glow discharge plasma, preferably dielectric barrier discharge plasma.

[0030] Furthermore, in the above-mentioned method for preparing the ortho-catalyst, the inert atmosphere is one or more of argon, nitrogen, or helium, with argon being preferred.

[0031] A second aspect of the present invention provides an ortho-configuration catalyst obtained by the above preparation method. The catalyst comprises a support and an active component. The support comprises a molecular sieve, which is one or more of ZSM-22 molecular sieve, ZSM-5 molecular sieve, and Y molecular sieve, preferably ZSM-22 molecular sieve. The active component is at least one of Group VIII noble metals Pt and Pd, preferably Pt.

[0032] A third aspect of the present invention provides the application of the above-mentioned ortho-assembly catalyst in the ortho-assembly reaction of isobutane.

[0033] Furthermore, in the above applications, the reaction conditions for the isobutane n-assembly reaction are: reaction temperature of 200℃-500℃, reaction pressure of 0.1 MPa-5.0 MPa, and feed space velocity of 0.1 h⁻¹. -1 - 10 h -1 .

[0034] Furthermore, in the above applications, the catalyst needs to be activated before the reaction. The activation conditions are: activation temperature of 200℃-500℃ and activation pressure of 0.1MPa-5.0MPa.

[0035] Compared with the prior art, the ortho-formation catalyst and its preparation method provided by the present invention have the following advantages:

[0036] 1. In the method for preparing the ortho-structured catalyst provided by this invention, a core-shell structured Pt / Pd@molecular sieve catalyst is prepared by in-situ synthesis. During the in-situ synthesis process, urea and other promoters are added to work synergistically with plasma. The added promoters are subjected to high-temperature treatment under a plasma atmosphere, which can decompose to generate more defect sites. These defect sites can improve the activity of the catalyst, requiring a lower reaction temperature to achieve the same reaction conditions. On the other hand, the defect sites can increase the carbon-holding capacity of the catalyst, thus giving the obtained catalyst good anti-carbon deposition performance. In addition, the ammonia gas generated by the decomposition of the promoters can generate hydrogen gas under the action of plasma, thereby achieving the directional reduction of Pt / Pd metal. This can save hydrogen gas and improve the activity of the catalyst.

[0037] 2. In the method for preparing the ortho-formation catalyst provided by the present invention, the molecular sieve is subjected to two-stage treatment under a plasma atmosphere, which can further improve the performance of the ortho-formation catalyst. Implementation

[0038] To better illustrate the present invention, the following description, in conjunction with embodiments and comparative examples, further explains the invention. However, the scope of the present invention is not limited to the scope of these embodiments.

[0039] In the context of this specification, specific surface area, pore volume, and average pore size were determined using a Micromeritics ASAP 2405 physical adsorption instrument with cryogenic liquid nitrogen physical adsorption. Prior to measurement, the samples were heat-treated at 300°C for 3 hours, followed by nitrogen adsorption at 77 K for testing. The specific surface area of ​​the molecular sieve was calculated using the BET method, and the total pore volume was within the p / p... 0 The value was measured at 0.98.

[0040] In this invention, the amount of carbon deposited on the catalyst material after the reaction was determined by thermogravimetric analysis (TGA / DSC 3+) using a Mettler Toledo thermal analysis system. All catalyst materials were tested at 370°C. o C. After reacting at 3.0 MPa for 24 h, thermogravimetric analysis was performed. During the test, the catalyst material was heated from room temperature to 900℃ in an air atmosphere at a heating rate of 20℃ / min.

[0041] In this invention, the plasma reactor used in the embodiments is a dielectric barrier discharge reactor (11 mm od × 8 mm id). A high-voltage electrode with a diameter of 2 mm is inserted in the middle of the reactor, and an aluminum foil sheet with a height of 3 cm is wound around the outer wall as a grounding electrode. The high-voltage electrode and the grounding electrode are respectively connected to the high-voltage electrode and the grounding electrode of the plasma power supply. The plasma power supply used is a CTP-2000K low-temperature plasma power supply. The reactor uses an insulating dielectric quartz tube to generate stable plasma.

[0042] In this invention, the plasma temperature is controlled by adjusting the power of the plasma power supply, and the plasma power is between 15-36 W within the temperature range.

[0043] Example 1

[0044] (1) Surface treatment of molecular sieves

[0045] Weigh 50 g of ZSM-22 molecular sieve and place it in a dielectric barrier discharge plasma reactor. First, treat it at 250 °C for 1 h in an argon atmosphere at a flow rate of 35 mL / min, and then treat it at 350 °C for 3 h in an argon and oxygen atmosphere at a flow rate of 80 mL / min (where the oxygen volume percentage is 30%).

[0046] (2) Loading of the precious metal Pt

[0047] Weigh 1.673 g of platinum nitrate, dissolve it in 10 mL of distilled water, add it to the material obtained in step (1), and age it at 40°C for 8 h.

[0048] (3) Crystallization treatment

[0049] Add water, tetrapropylammonium hydroxide and urea to the material obtained in step (2), wherein the molar ratio of the material obtained in step (2), water, tetrapropylammonium hydroxide and urea is 1:60:1:3. After stirring evenly, transfer it to a reaction vessel lined with polytetrafluoroethylene and crystallize it at 170°C for 24 h. After natural cooling, wash the product with water and then dry it in an oven at 120°C for 12 h.

[0050] (4) Heat treatment

[0051] The material obtained in step (3) was placed in a dielectric barrier discharge plasma reaction tube and subjected to an argon atmosphere at a flow rate of 40 mL / min at 400 °C. o The desired ortho-formation catalyst can be obtained by treating with C for 2 h.

[0052] The above-mentioned n-assembly catalyst was applied to the n-assembly reaction of isobutane under the following conditions: reaction temperature was 370°C. o C, the reaction pressure is 3.0 MPa, and the feed gas space velocity is 0.77 h⁻¹. -1 Specifically, the catalyst needs to be activated before the reaction. The activation conditions are: hydrogen flow rate of 30 mL / min, activation temperature of 370℃, and activation pressure of 3.0 MPa.

[0053] The properties and evaluation results of the catalyst are shown in Table 1.

[0054] Example 2

[0055] (1) Surface treatment of molecular sieves

[0056] Weigh 50 g of ZSM-22 molecular sieve and place it in a dielectric barrier discharge plasma reactor. First, treat it at 250 °C for 1 h in an argon atmosphere at a flow rate of 35 mL / min, and then treat it at 300 °C for 3 h in an argon and oxygen atmosphere at a flow rate of 80 mL / min (where the oxygen volume percentage is 30%).

[0057] (2) Loading of the precious metal Pt

[0058] Weigh 0.862 g of tetraammonium dichloride platinum, dissolve it in 10 mL of distilled water, add it to the material obtained in step (1), and age it at 60°C for 10 h;

[0059] (3) Crystallization treatment

[0060] Add water, tetrapropylammonium hydroxide and ammonium bicarbonate to the material obtained in step (2), wherein the molar ratio of the material obtained in step (2), water, tetrapropylammonium hydroxide and ammonium bicarbonate is 1:45:1.5:2. After stirring evenly, transfer it to a reaction vessel lined with polytetrafluoroethylene and crystallize it at 170°C for 24 h. After natural cooling, wash the product with water and then dry it in an oven at 120°C for 12 h.

[0061] (4) Heat treatment

[0062] The material obtained in step (3) was placed in a dielectric barrier discharge plasma reaction tube and heated in an argon atmosphere at 375 °C at a flow rate of 40 mL / min. o The desired catalyst can be obtained by treating with C for 2 hours.

[0063] The above catalyst was applied to the isobutane n-assembly reaction under the following conditions: reaction temperature was 370°C. o C, the reaction pressure is 3.0 MPa, and the feed gas space velocity is 0.77 h⁻¹. -1 Specifically, the catalyst needs to be activated before the reaction. The activation conditions are: hydrogen flow rate of 30 mL / min, activation temperature of 370℃, and activation pressure of 3.0 MPa.

[0064] The properties and evaluation results of the catalyst are shown in Table 1.

[0065] Example 3

[0066] (1) Surface treatment of molecular sieves

[0067] Weigh 50 g of ZSM-22 molecular sieve and place it in a dielectric barrier discharge plasma reactor. First, treat it at 250 °C for 1 h in an argon atmosphere at a flow rate of 40 mL / min, and then treat it at 350 °C for 3 h in an argon and oxygen atmosphere at a flow rate of 80 mL / min (where the oxygen volume percentage is 35%).

[0068] (2) Loading of the precious metal Pt

[0069] Weigh 0.573 g of chloroplatinic acid, dissolve it in 10 mL of distilled water, add it to the material obtained in step (1), and age it at 80°C for 6 h.

[0070] (3) Crystallization treatment

[0071] Add water, tetrabutylammonium bromide and urea to the material obtained in step (2), wherein the molar ratio of the material obtained in step (2), water, tetrabutylammonium bromide and urea is 1:40:1:0.5. After stirring evenly, transfer it to a reaction vessel lined with polytetrafluoroethylene and crystallize it at 180°C for 48 h. After natural cooling, wash the product with water and then dry it in an oven at 100°C for 12 h.

[0072] (4) Heat treatment

[0073] The material obtained in step (3) was placed in a dielectric barrier discharge plasma reaction tube and subjected to a helium atmosphere at a flow rate of 50 mL / min at 400 °C. o The desired catalyst can be obtained by treating with C for 2 hours.

[0074] The above catalyst was applied to the isobutane n-assembly reaction under the following conditions: reaction temperature was 370°C. o C, the reaction pressure is 3.0 MPa, and the feed gas space velocity is 0.77 h⁻¹. -1 Specifically, the catalyst needs to be activated before the reaction. The activation conditions are: hydrogen flow rate of 30 mL / min, activation temperature of 370℃, and activation pressure of 3.0 MPa.

[0075] The properties and evaluation results of the catalyst are shown in Table 1.

[0076] Example 4

[0077] (1) Surface treatment of molecular sieves

[0078] Weigh 50 g of ZSM-22 molecular sieve and place it in a dielectric barrier discharge plasma reactor. First, treat it at 250 °C for 1 h in an argon atmosphere at a flow rate of 35 mL / min, and then treat it at 350 °C for 3 h in an argon and oxygen atmosphere at a flow rate of 80 mL / min (where the oxygen volume percentage is 30%).

[0079] (2) Loading of the precious metal Pt

[0080] Weigh 0.826 g of platinum nitrate, dissolve it in 10 mL of distilled water, add it to the material obtained in step (1), and age it at 50°C for 8 h.

[0081] (3) Crystallization treatment

[0082] Add water and tetrapropylammonium hydroxide to the material obtained in step (2), wherein the molar ratio of the material obtained in step (2), water and tetrapropylammonium hydroxide is 1:50:1. After stirring evenly, transfer it to a reaction vessel lined with polytetrafluoroethylene and crystallize it at 200°C for 24 h. After natural cooling, wash the product with water and then dry it in an oven at 120°C for 12 h.

[0083] (4) Heat treatment

[0084] The material obtained in step (3) was placed in a dielectric barrier discharge plasma reaction tube and subjected to an argon atmosphere at a flow rate of 40 mL / min at 400 °C. o The desired catalyst can be obtained by treating with C for 2 hours.

[0085] The above catalyst was applied to the isobutane n-assembly reaction under the following conditions: reaction temperature was 370°C. o C, the reaction pressure is 3.0 MPa, and the feed gas space velocity is 0.77 h⁻¹. -1 Specifically, the catalyst needs to be activated before the reaction. The activation conditions are: hydrogen flow rate of 30 mL / min, activation temperature of 370℃, and activation pressure of 3.0 MPa.

[0086] The properties and evaluation results of the catalyst are shown in Table 1.

[0087] Example 5

[0088] (1) Surface treatment of molecular sieves

[0089] Weigh 50 g of ZSM-5 molecular sieve and place it in a dielectric barrier discharge plasma reactor. First, treat it at 300℃ for 1.5 h in an argon atmosphere at a flow rate of 50 mL / min. Then, treat it at 350℃ for 3 h in an argon and oxygen atmosphere at a flow rate of 50 mL / min (where the oxygen volume percentage is 50%).

[0090] (2) Loading of the precious metal Pt

[0091] Weigh 0.428 g of tetraammonium dichloride platinum, dissolve it in 10 mL of distilled water, add it to the material obtained in step (1), and age it at 40°C for 8 h;

[0092] (3) Crystallization treatment

[0093] Add water and tetrabutylammonium bromide to the material obtained in step (2), wherein the molar ratio of the material obtained in step (2), water and tetrabutylammonium bromide is 1:30:0.5. After stirring evenly, transfer it to a reaction vessel lined with polytetrafluoroethylene and crystallize it at 180°C for 24 h. After natural cooling, wash the product with water and then dry it in an oven at 120°C for 12 h.

[0094] (4) Heat treatment

[0095] The material obtained in step (3) is roasted in a muffle furnace at 540°C for 4 hours.

[0096] The above catalyst was applied to the isobutane n-assembly reaction under the following conditions: reaction temperature was 370°C. o C, the reaction pressure is 3.0 MPa, and the feed gas space velocity is 0.77 h⁻¹. -1 Specifically, the catalyst needs to be activated before the reaction. The activation conditions are: hydrogen flow rate of 30 mL / min, activation temperature of 370℃, and activation pressure of 3.0 MPa.

[0097] The properties and evaluation results of the catalyst are shown in Table 1.

[0098] Example 6

[0099] (1) Loading of the precious metal Pt

[0100] Weigh 2.327 g of chloroplatinic acid, dissolve it in 10 mL of distilled water, add it to 50 g of Y-type molecular sieve, and age it at 40℃ for 8 h.

[0101] (2) Crystallization treatment

[0102] Add water and tetrapropylammonium hydroxide to the material obtained in step (1), wherein the molar ratio of the material obtained in step (2), water and tetrapropylammonium hydroxide is 1:60:2. After stirring evenly, transfer it to a reaction vessel lined with polytetrafluoroethylene and crystallize it at 200°C for 24 h. After natural cooling, wash the product with water and then dry it in an oven at 120°C for 12 h.

[0103] (3) Heat treatment

[0104] The material obtained in step (2) was placed in a dielectric barrier discharge plasma reaction tube and subjected to an argon atmosphere at a flow rate of 40 mL / min at 400 °C. o The desired catalyst can be obtained by treating with C for 2 hours.

[0105] The above catalyst was applied to the isobutane n-assembly reaction under the following conditions: reaction temperature was 370°C. oC, the reaction pressure is 3.0 MPa, and the feed gas space velocity is 0.77 h⁻¹. -1 Specifically, the catalyst needs to be activated before the reaction. The activation conditions are: hydrogen flow rate of 30 mL / min, activation temperature of 370℃, and activation pressure of 3.0 MPa.

[0106] The properties and evaluation results of the catalyst are shown in Table 1.

[0107] Comparative Example 1

[0108] (1) Loading of the precious metal Pt

[0109] Weigh 0.825 g of platinum nitrate, dissolve it in 3 mL of distilled water, add it to 50 g of ZSM-22 molecular sieve, and age it at 40℃ for 8 h.

[0110] (2) Crystallization treatment

[0111] Add water and tetrapropylammonium hydroxide to the material obtained in step (1), wherein the molar ratio of the material obtained in step (1), water and tetrapropylammonium hydroxide is 1:60:1. After stirring evenly, transfer it to a reaction vessel lined with polytetrafluoroethylene and crystallize it at 170°C for 24 h. After natural cooling, wash the product with water and then dry it in an oven at 120°C for 12 h.

[0112] (3) Heat treatment

[0113] The material obtained in step (3) is roasted in a muffle furnace at 540°C for 4 hours.

[0114] The above catalyst was applied to the isobutane n-assembly reaction under the following conditions: reaction temperature was 370°C. o C, the reaction pressure is 3.0 MPa, and the feed gas space velocity is 0.77 h⁻¹. -1 Specifically, the catalyst needs to be activated before the reaction. The activation conditions are: hydrogen flow rate of 30 mL / min, activation temperature of 370℃, and activation pressure of 3.0 MPa.

[0115] The properties and evaluation results of the catalyst are shown in Table 1.

[0116] Table 1. Properties and evaluation results of the catalyst

[0117]

Claims

1. A process for the preparation of a normalisation catalyst, characterised in that: The preparation method comprises the following contents: (1) surface treatment of molecular sieve: the molecular sieve is treated in the atmosphere of plasma; (2) loading of active component: the precursor solution containing active component is uniformly mixed with the material obtained in step (1), and then aging treatment is carried out; (3) crystallization treatment: the material obtained in step (2), water and template agent are uniformly mixed and subjected to crystallization treatment, and then the normal paraffinization catalyst is obtained after washing, drying and heat treatment; the molecular sieve in step (1) is selected from one or more of ZSM-22 molecular sieve, ZSM-5 molecular sieve and Y molecular sieve; the treatment of the molecular sieve in step (1) in the atmosphere of plasma comprises two stages, the material obtained after one-stage treatment of the molecular sieve in the atmosphere of plasma is subjected to two-stage treatment in the atmosphere of plasma; the one-stage treatment temperature is 250-350 DEG C, and the atmosphere of one-stage treatment is argon; the two-stage treatment temperature is 25-250 DEG C higher than the one-stage treatment temperature, and the atmosphere of two-stage treatment is the mixed gas of inert gas and oxygen; the active component in step (2) is Pt and / or Pd; an additive is introduced in step (3), and the specific introduction process is that the additive is uniformly mixed with the material obtained in step (2), water and template agent, and then subjected to crystallization treatment; the additive is one or more of urea, ammonium oxalate, ammonium carbonate and ammonium bicarbonate.

2. The method of claim 1, wherein: the molecular sieve in step (1) is ZSM-22 molecular sieve.

3. The method of claim 1, wherein: the plasma in step (1) is one or more of dielectric barrier discharge plasma, sliding arc discharge plasma and glow discharge plasma.

4. The method of claim 3, wherein: the plasma in step (1) is dielectric barrier discharge plasma.

5. The method of claim 1, wherein: the atmosphere of the plasma in step (1) is derived from inert gas or the mixed gas of inert gas and oxygen, the volume percentage content of oxygen in the mixed gas is 20-70 %, and the inert gas is at least one of argon, helium and nitrogen.

6. The method of claim 5, wherein: in step (1), the volume percentage content of oxygen in the mixed gas is 30-50 %, and the inert gas is argon.

7. The method of claim 1, wherein: the specific operation process of the treatment in the atmosphere of plasma in step (1) is as follows: the molecular sieve is placed in a plasma reactor, treated in the inert gas or the mixed gas of inert gas and oxygen at 250-500 DEG C for 0.5-5 h, and the volume flow rate of the inert gas or the mixed gas of inert gas and oxygen is 20-150 mL / min.

8. The method of claim 7, wherein: the specific operation process of the treatment in the atmosphere of plasma in step (1) is as follows: the molecular sieve is placed in a plasma reactor, treated in the inert gas or the mixed gas of inert gas and oxygen at 250-450 DEG C for 0.5-3 h, and the volume flow rate of the inert gas or the mixed gas of inert gas and oxygen is 35-100 mL / min.

9. The method of claim 1, wherein: In step (1), the first-stage treatment temperature is 250-300°C, and the first-stage treatment time is 0.5-3 hours; the second-stage treatment temperature is 50-200°C higher than the first-stage treatment temperature; and the second-stage treatment time is 0.5-3 hours longer than the first-stage treatment time.

10. The method of claim 1, wherein: In step (1), the first-stage treatment time is 0.5-1 hour, and the second-stage treatment time is 1-2 hours longer than the first-stage treatment time.

11. The method of claim 1, wherein: In step (2), the active component is Pt; and the active-component-containing precursor solution is one or more of an aqueous solution of chloroplatinic acid, platinum nitrate, dichlorotetraamine platinum, palladium acetate, palladium chloride, palladium nitrate, sodium chloropalladate, potassium chloropalladate, and dichlorotetraamine palladium.

12. The method of claim 11, wherein: In step (2), the active-component-containing precursor solution is an aqueous solution of platinum nitrate or dichlorotetraamine platinum.

13. The method of claim 1, wherein: In step (2), the mass ratio of the material obtained in step (1) to the active-component-containing precursor is (20-150):

1.

14. The method of claim 13, wherein: In step (2), the mass ratio of the material obtained in step (1) to the active-component-containing precursor is (30-100):

1.

15. The method of claim 1, wherein: In step (2), the mixing is performed by impregnation, and the impregnation process is one-step impregnation or multi-step impregnation.

16. The method of claim 15, wherein: In step (2), the impregnation process is multi-step impregnation.

17. The method of claim 1, wherein: In step (2), the aging time is 2-24 hours, and the aging temperature is 30-100°C.

18. The method of claim 17, wherein: In step (2), the aging time is 6-10 hours, and the aging temperature is 40-80°C.

19. The method of claim 1, wherein: In step (3), the additive is urea and / or ammonium bicarbonate; and the molar ratio of the material obtained in step (2) to the additive is 1:(0.1-6).

20. The method of claim 19, wherein: In step (3), the molar ratio of the material obtained in step (2) to the additive is 1:(0.5-3).

21. The method of claim 1, wherein: In step (3), the template agent is one or more of tetrapropylammonium hydroxide, tetrapropylammonium bromide, tetrabutylammonium bromide, tetraethylammonium hydroxide, and triethylamine.

22. The method of claim 21, wherein: In step (3), the template agent is tetrapropylammonium hydroxide.

23. The method of claim 1, wherein: In step (3), the molar ratio of the material obtained in step (2), water, and the template agent is 1:(20-100):(0.05-4).

24. The method of claim 23, wherein: In step (3), the molar ratio of the material obtained in step (2), water, and the template agent is 1:(30-60):(0.1-2).

25. The method of claim 1, wherein: In step (3), the crystallization treatment conditions are as follows: the crystallization time is 12-48 hours, and the crystallization temperature is 130-250°C.

26. The method of claim 25, wherein: In step (3), the crystallization treatment conditions are as follows: the crystallization time is 12-36 hours, and the crystallization temperature is 150-200°C.

27. The method of claim 1, wherein: In step (3), the drying temperature is 80-200°C, and the drying time is 6-48 hours.

28. The method of claim 27, wherein: In step (3), the drying temperature is 80-120°C, and the drying time is 6-36 hours.

29. The method of claim 27, wherein: In step (3), the drying time is 6-24 hours.

30. The method of claim 1, wherein: In step (3), the heat treatment is calcination and / or plasma treatment.

31. The method of claim 30, wherein: In step (3), the heat treatment is plasma treatment.

32. The method of claim 30, wherein: When the heat treatment in step (3) is calcination, the calcination temperature is 400-600°C, and the treatment time is 2-6 hours.

33. The method of claim 32, wherein: When the heat treatment in step (3) is calcination, the calcination temperature is 450-550°C, and the treatment time is 2-5 hours.

34. The method of claim 32, wherein: When the heat treatment in step (3) is calcination, the treatment time is 3-4 hours.

35. The method of claim 30, wherein: When the heat treatment in step (3) is plasma treatment, the specific operation process of the plasma treatment is as follows: the material obtained after drying in step (3) is placed in a plasma reactor, and is treated at 350-400°C for 1-3 hours in an inert atmosphere with a flow rate of 25-60 mL / min.

36. The method of claim 35, wherein: When the heat treatment in step (3) is plasma treatment, the specific operation process of the plasma treatment is as follows: the material obtained after drying in step (3) is placed in a plasma reactor, and is treated at 350-400°C for 1-2 hours in an inert atmosphere with a flow rate of 35-50 mL / min.

37. A normalizer catalyst prepared by the method of any one of claims 1-36.

38. Use of the normalizer catalyst of claim 37 in the normalization reaction of isobutane.

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