阅读说明：本技术 一种加氢裂化催化剂及其制备方法和应用 (Hydrocracking catalyst, and preparation method and application thereof ) 是由 郭蓉 柳伟 杜艳泽 秦波 高杭 张晓萍 于 2019-10-28 设计创作，主要内容包括：本发明公开一种加氢裂化催化剂及其制备方法和应用,所述方法包括如下过程：(1)将改性Y分子筛、无定型硅铝和/或氧化铝成型,经干燥、焙烧制得催化剂载体；所述改性Y分子筛中钠含量为1～8wt%；(2)采用非极性有机溶剂饱和浸渍步骤(1)制备的催化剂载体,然后进行干燥处理,干燥至催化剂载体中非极性有机溶剂的含量为催化剂载体饱和吸附量的20-90%。(3)对步骤(2)获得的物料进行铵盐离子交换、干燥、焙烧处理；(4)在步骤(3)获得的物料上引入活性金属,经干燥、焙烧得到最终催化剂。所述方法制备的催化剂能够减少高附加值润滑油基础油裂化生成其它低价值产品,特别是减少润滑油基础油中直链烷烃高粘度指数组分的过度裂化。(The invention discloses a hydrocracking catalyst and a preparation method and application thereof, wherein the method comprises the following steps: (1) forming the modified Y molecular sieve and amorphous silicon-aluminum and/or aluminum oxide, drying and roasting to obtain a catalyst carrier; the sodium content in the modified Y molecular sieve is 1-8 wt%; (2) and (2) saturating and dipping the catalyst carrier prepared in the step (1) by adopting a non-polar organic solvent, and then drying until the content of the non-polar organic solvent in the catalyst carrier is 20-90% of the saturated adsorption amount of the catalyst carrier. (3) Performing ammonium salt ion exchange, drying and roasting treatment on the material obtained in the step (2); (4) and (4) introducing active metal into the material obtained in the step (3), and drying and roasting to obtain the final catalyst. The catalyst prepared by the method can reduce the cracking of the high value-added lubricant base oil to generate other low-value products, and particularly reduce the excessive cracking of the high-viscosity index component of the straight-chain alkane in the lubricant base oil.)

1. A preparation method of a hydrocracking catalyst is characterized by comprising the following steps: the method comprises the following steps:

(1) forming the modified Y molecular sieve and amorphous silicon-aluminum and/or aluminum oxide, drying and roasting to obtain a catalyst carrier; the sodium content in the modified Y molecular sieve is 1-8 wt%, preferably 1.5-6 wt%, and further preferably 3-5 wt%; the properties of the modified Y molecular sieve are as follows SiO₂/Al₂O₃The molar ratio is 12-50, the pore volume is 0.38-0.50ml/g, the specific surface area is 650-850m²(iv)/g, crystallinity 70% -90%;

(2) saturating and dipping the catalyst carrier prepared in the step (1) by using a nonpolar organic solvent, and then drying until the content of the nonpolar organic solvent in the catalyst carrier is 20-90%, preferably 30-80%, and further preferably 40-70% of the saturated adsorption capacity of the catalyst carrier;

(3) performing ammonium salt ion exchange, drying and roasting treatment on the material obtained in the step (2);

(4) and (4) introducing active metal into the material obtained in the step (3), and drying and roasting to obtain the final catalyst.

2. The method of claim 1, wherein: in the step (1), the modified Y molecular sieve, amorphous silicon aluminum and/or aluminum oxide are uniformly mixed according to a certain proportion, and then are rolled and molded.

3. The method of claim 1, wherein: the catalyst carrier in the step (1) is spherical, strip-shaped, clover or clover.

4. The method of claim 1, wherein: drying the catalyst carrier formed in the step (1) at 80-120 ℃ for 1-5 h, and roasting at 500-600 ℃ for 1-5 h.

5. The method of claim 1, wherein: the preparation process of the modified Y molecular sieve in the step (1) is as follows: 1) carrying out ammonium salt exchange by using NaY zeolite as raw powder; 2) treating the material subjected to ammonium salt exchange in the step 1), wherein the treatment comprises one or more of hydro-thermal treatment and chemical treatment; 3) and (3) carrying out alkali metal ion exchange, preferably sodium ion exchange on the material treated in the step 2), and drying and roasting to obtain the modified Y molecular sieve.

6. The method of claim 5, wherein: the specific preparation process of the modified Y molecular sieve is as follows:

1) performing ammonium salt ion exchange to Na in ammonium salt solution by using NaY zeolite as raw powder₂The weight content of O is less than 3 percent;

2) carrying out hydrothermal treatment on the ammonium exchange sample obtained in the step 1);

3) treating the Y molecular sieve subjected to the hydro-thermal treatment in the step 2) with a nitric acid aqueous solution;

4) performing sodium ion exchange on the hydrothermal Y molecular sieve obtained in the step (3) in a sodium salt solution;

5) and (4) drying and roasting the sodium ion exchange molecular sieve to obtain the modified molecular sieve.

7. The method of claim 6, wherein: the process of the ammonium salt ion exchange in step 1) is as follows: exchanging NaY zeolite serving as a raw material in an ammonium salt water solution at 50-110 ℃, preferably 60-80 ℃ for 1-2 hours for 1-3 times to obtain exchanged NaY zeolite and Na₂O containsThe amount is less than 3.0%; wherein the SiO of the raw material of the NaY zeolite₂/Al₂O₃The molar ratio is 3-6, and the mass percentage of the sodium oxide is 8% -12%; the ammonium salt is one or more of ammonium chloride, ammonium nitrate, ammonium sulfate, ammonium acetate or ammonium oxalate, and the concentration of the ammonium salt aqueous solution is 0.3-6.0 mol/L, preferably 1.0-3.0 mol/L.

8. The method of claim 6, wherein: step 2) hydrothermal treatment conditions are as follows: the temperature is 590-700 ℃, the pressure is 0.05-0.4 MPa, the treatment time is 3.0-5.0 hours, and the hydrothermal treatment times are 2-4.

9. The method of claim 6, wherein: step 3) nitric acid aqueous solution treatment conditions: with H⁺The concentration of acid in the solution is 0.6-2.0 mol/L, the treatment temperature is 60-100 ℃, the treatment time is 2-4 h, and the liquid-solid ratio is 5: 1-15: 1.

10. The method of claim 6, wherein: step 4) Na (NO) is used in the ion exchange process of the sodium salt solution₃) Adding Na (NO) with the concentration of 1.0-3.0 mol/L in terms of sodium ions into the Y molecular sieve treated by the dilute nitric acid in the step (3) to obtain an aqueous solution₃) Heating the mixture to 40-80 ℃ in the aqueous solution, and reacting for 1-4 h at constant temperature.

11. The method of claim 6, wherein: step 5), drying at the temperature of 100 ℃ and 150 ℃ for 2-6 h; the roasting condition is 400-600 ℃, and the time is 2-6 h.

12. The method of claim 1, wherein: the nonpolar organic solvent in the step (2) comprises one or more of paraffin, petroleum ether, carbon tetrachloride, benzene, toluene, ethylbenzene and xylene; and (2) saturating and dipping the catalyst carrier prepared in the step (1) by using a nonpolar organic solvent for 1-5 hours, and drying the carrier dipped with the nonpolar organic solvent at 50-300 ℃ for 1-60 minutes, preferably 3-20 minutes.

13. The method of claim 1, wherein: na (NO) is used in the ammonium salt ion exchange process in the step (3)₃) Adding Na (NO) with the concentration of 1.0-3.0 mol/L in terms of sodium ions into the Y molecular sieve in the step (2) to obtain an aqueous solution₃) Heating the mixture to 40-80 ℃ in the aqueous solution, and reacting for 1-4 h at constant temperature.

14. The method of claim 1, wherein: in the step (3), the drying temperature is 100-150 ℃, the drying time is 2-6h, the roasting temperature is 400-600 ℃, and the roasting time is 2-6 h.

15. The method of claim 1, wherein: and (4) introducing the active metal in the step (4) by adopting an impregnation method, and carrying out over-volume impregnation, equal-volume impregnation or spraying impregnation.

16. The method of claim 1, wherein: in the step (4), the active metal is a metal element in a VIII group and/or a VI group in the periodic table of elements; the active metal of the VIII family is Ni and/or Co, and the active metal of the VI family is W and/or Mo.

17. The method of claim 1, wherein: in the step (4), the drying temperature is 100-150 ℃, the drying time is 2-6h, the roasting temperature is 400-500 ℃, and the roasting time is 2-6 h.

18. A hydrocracking catalyst prepared by the process of any one of claims 1 to 17, characterized in that: the catalyst contains a silicon-aluminum carrier containing a Y molecular sieve and an active metal, and the contents of the silicon-aluminum carrier containing the Y molecular sieve and the active metal are respectively 60-85% and 15-40% by mass percent based on the mass of the final catalyst; wherein the mass percentage of the active metal is measured as the oxide metal.

19. The catalyst in accordance with claim 18, wherein,the method is characterized in that: the specific surface area of the catalyst is 200-400 m²A pore volume of 0.2 to 0.5ml/g, Na₂The content of O is 0.2% -2%.

20. Use of the catalyst of claim 18 in the production of lube base oil in a single stage serial hydrocracking process, wherein: the wax oil reaction raw material firstly passes through a pre-refining reactor to complete the refining reaction, and then the reaction effluent of the pre-refining reactor enters a cracking reactor to react.

21. In the above application, according to claim 20, wherein: the reaction process comprises the following process conditions: the reaction process conditions of the pre-refining reactor are as follows: the reaction pressure is 10.0-20.0 Mpa; the volume airspeed is 0.5-2.0 h^-1(ii) a The reaction temperature is 350-420 ℃; the volume ratio of hydrogen to oil is 500-2000; the operating conditions of the cracking reactor are that the reaction pressure is 10.0-20.0 Mpa; the volume airspeed is 0.1-0.5 h^-1(ii) a The reaction temperature is 350-420 ℃; the volume ratio of hydrogen to oil is 500-2000.

Technical Field

The invention relates to a hydrocracking catalyst, a preparation method and application thereof, in particular to a high-yield high-quality lubricating oil base oil hydrocracking catalyst, and a preparation method and application thereof.

Background

The hydrocracking process comprises two processes of cracking and hydrogenation, wherein on one hand, heavy raw oil is cracked and converted into light distillate oil components, and on the other hand, hydrogenation is carried out while cracking so as to improve the product quality. For the hydrocracking catalyst, the reaction characteristics and the performance of the catalyst are determined by the hydrogenation activity and the cracking activity blending mode.

At present, the preparation methods of hydrocracking catalysts are mainly divided into two main categories: kneading and dipping. The kneading method is that active metal components are mixed with molecular sieve, alumina and amorphous silica-alumina carrier material, and the mixture is rolled and directly extruded into strips for molding; the impregnation method first prepares the support and then impregnates the active metal component. No matter the catalyst is prepared by adopting a kneading method or an impregnation method, the hydrogenation activity and the cracking activity of different parts inside and outside the catalyst are uniformly distributed, and the current preparation method cannot realize the differential matching of the internal and external hydrogenation activity and the cracking activity of the catalyst.

The preparation method of the mild hydrocracking catalyst is provided by the US patent 5,229,347, the prepared catalyst takes VIB and VIII as active metal components, the metal components are introduced by adopting an impregnation method, the catalytic activity of the prepared finished catalyst is uniform inside and outside, and the differential matching of the internal and external hydrogen activity of the catalyst and the cracking activity cannot be realized.

Patent CN96109702.7 describes a preparation method of a hydrocracking catalyst, which comprises the steps of firstly preparing a catalyst carrier containing a Y-type molecular sieve and a refractory inorganic oxide, and then impregnating the prepared carrier with a co-immersion liquid composed of ammonium metatungstate and nickel nitrate to obtain the hydrocracking catalyst.

Disclosure of Invention

Aiming at the defects of the prior art, the invention provides a hydrocracking catalyst, a preparation method and application thereof. The catalyst can reduce the cracking of the high value-added lubricant base oil to generate other low-value products, and particularly reduce the excessive cracking of high-viscosity index components of straight-chain paraffin in the lubricant base oil.

A method for preparing a hydrocracking catalyst, the method comprising the steps of:

(1) forming the modified Y molecular sieve and amorphous silicon-aluminum and/or aluminum oxide, drying and roasting to obtain a catalyst carrier; the sodium content in the modified Y molecular sieve is 1-8 wt%, preferably 1.5-6 wt%, and further preferably 3-5 wt%; the properties of the modified Y molecular sieve are as follows SiO₂/Al₂O₃The molar ratio is 12-50, the pore volume is 0.38-0.50ml/g, the specific surface area is 650-850m²(iv)/g, crystallinity 70% -90%;

(2) saturating and dipping the catalyst carrier prepared in the step (1) by using a nonpolar organic solvent, and then drying until the content of the nonpolar organic solvent in the catalyst carrier is 20-90%, preferably 30-80%, and further preferably 40-70% of the saturated adsorption capacity of the catalyst carrier;

(3) performing ammonium salt ion exchange, drying and roasting treatment on the material obtained in the step (2);

(4) and (4) introducing active metal into the material obtained in the step (3), and drying and roasting to obtain the final catalyst.

In the method, the modified Y molecular sieve, the amorphous silicon-aluminum and/or the aluminum oxide are uniformly mixed according to a certain proportion in the step (1), and are rolled and molded.

In the method, the catalyst carrier in the step (1) is spherical, strip-shaped, clover or clover.

In the method, the catalyst carrier formed in the step (1) is dried at 80-120 ℃ for 1-5 h, and is roasted at 500-600 ℃ for 1-5 h.

In the method, the preparation process of the modified Y molecular sieve in the step (1) is as follows: 1) carrying out ammonium salt exchange by using NaY zeolite as raw powder; 2) treating the material subjected to ammonium salt exchange in the step 1), wherein the treatment comprises one or more of hydro-thermal treatment and chemical treatment; 3) and (3) carrying out alkali metal ion exchange, preferably sodium ion exchange on the material treated in the step 2), and drying and roasting to obtain the modified Y molecular sieve.

In one or more embodiments of the present invention, the modified Y molecular sieve is prepared as follows:

1) performing ammonium salt ion exchange to Na in ammonium salt solution by using NaY zeolite as raw powder₂The weight content of O is less than 3 percent;

2) carrying out hydrothermal treatment on the ammonium exchange sample obtained in the step 1);

3) treating the Y molecular sieve subjected to the hydro-thermal treatment in the step 2) with a nitric acid aqueous solution;

4) performing sodium ion exchange on the hydrothermal Y molecular sieve obtained in the step (3) in a sodium salt solution;

5) and (4) drying and roasting the sodium ion exchange molecular sieve to obtain the modified molecular sieve.

The process of the ammonium salt ion exchange in step 1) is as follows: exchanging NaY zeolite serving as a raw material in an ammonium salt water solution at 50-110 ℃, preferably 60-80 ℃ for 1-2 hours for 1-3 times to obtain exchanged NaY zeolite and Na₂The content of O is less than 3.0 percent; wherein the SiO of the raw material of the NaY zeolite₂/Al₂O₃The molar ratio is 3-6, and the mass percentage of the sodium oxide is 8% -12%; the ammonium salt is one or more of ammonium chloride, ammonium nitrate, ammonium sulfate, ammonium acetate or ammonium oxalate, and the concentration of the ammonium salt aqueous solution is 0.3-6.0 mol/L, preferably 1.0-3.0 mol/L.

Step 2) hydrothermal treatment conditions are as follows: the temperature is 590-700 ℃, the pressure is 0.05-0.4 MPa, the treatment time is 3.0-5.0 hours, and the hydrothermal treatment times are 2-4.

Step 3) nitric acid aqueous solution treatment conditions: with H⁺The concentration of acid in the solution is 0.6-2.0 mol/L, and the treatment temperature isThe treatment time is 2-4 h at the temperature of 60-100 ℃, and the liquid-solid ratio is 5: 1-15: 1.

Step 4) Na (NO) is used in the ion exchange process of the sodium salt solution₃) Adding Na (NO) with the concentration of 1.0-3.0 mol/L (calculated by sodium ions) into the Y molecular sieve treated by the dilute nitric acid in the step (3) to obtain an aqueous solution₃) Heating the mixture to 40-80 ℃ in the aqueous solution, and reacting for 1-4 h at constant temperature;

step 5), drying at the temperature of 100 ℃ and 150 ℃ for 2-6 h; the roasting condition is 400-600 ℃, and the time is 2-6 h.

In the above method, the nonpolar organic solvent in step (2) includes one or more of paraffin, petroleum ether, carbon tetrachloride, benzene, toluene, ethylbenzene, and xylene; and (2) saturating and dipping the catalyst carrier prepared in the step (1) by using a nonpolar organic solvent for 1-5 hours, and drying the carrier dipped with the nonpolar organic solvent at 50-300 ℃ for 1-60 minutes, preferably 3-20 minutes. The carrier impregnated with the nonpolar organic solvent is dried to remove the organic solvent outside the carrier, and the inside of the carrier is filled with the organic solvent, so that only sodium ions on the surface are exchanged in the ammonia exchange step, and the outside of the catalyst carrier has cracking activity, and the inside of the catalyst carrier only has hydrogenation activity.

In the method, Na (NO) is used in the ammonium salt ion exchange process in the step (3)₃) Adding Na (NO) with the concentration of 1.0-3.0 mol/L (calculated by sodium ions) into the Y molecular sieve in the step (2) to form an aqueous solution₃) Heating the mixture to 40-80 ℃ in the aqueous solution, and reacting for 1-4 h at constant temperature.

In the method, in the step (3), the drying temperature is 100-.

In the method, the active metal is introduced in the step (4) by adopting an impregnation method, and the over-volume impregnation, the equal-volume impregnation and the spraying impregnation can be carried out, and the impregnation can be carried out once or for multiple times.

In the above method, the active metal in step (4) may be a metal element of group VIII and/or group VI of the periodic table of elements; the group VIII active metal may be Ni and/or Co and the group VI active metal may be W and/or Mo.

In the method, in the step (4), the drying temperature is 100-.

The hydrocracking catalyst prepared by the method contains a silicon-aluminum carrier containing a Y molecular sieve and an active metal, and the contents of the silicon-aluminum carrier containing the Y molecular sieve and the active metal are respectively 60-85% and 15-40% by mass percent on the basis of the mass of the final catalyst; wherein the mass percentage of the active metal is measured as the oxide metal.

In the hydrocracking catalyst, the specific surface area of the catalyst is 200-400 m²A pore volume of 0.2 to 0.5ml/g, Na₂The content of O is 0.2% -2%. The hydrogenation active metal can be metal elements in a VIII group and/or a VI group in the periodic table of elements, the VIII group active metal can be Ni and/or Co, the VI group active metal is W and/or Mo, the content of the VIII group active metal is generally 3-15% by oxide, and the content of the VI group active metal is generally 10-40% by oxide. The mass content of the Y molecular sieve in the carrier is generally 1-40%, preferably 3-20%, and the balance is amorphous silica-alumina and/or alumina.

When the hydrocracking catalyst is used for producing the lubricating oil base oil by the single-stage series hydrocracking process flow, the wax oil reaction raw material firstly passes through the pre-refining reactor to complete the refining reaction, and then the reaction effluent of the pre-refining reactor enters the cracking reactor to react.

In the application, the reaction process has the following process conditions: the reaction process conditions of the pre-refining reactor are as follows: the reaction pressure is 10.0-20.0 Mpa; the volume airspeed is 0.5-2.0 h^-1(ii) a The reaction temperature is 350-420 ℃; the volume ratio of hydrogen to oil is 500-2000; the operating conditions of the cracking reactor are that the reaction pressure is 10.0-20.0 Mpa; the volume airspeed is 0.1-0.5 h^-1(ii) a The reaction temperature is 350-420 ℃; the volume ratio of hydrogen to oil is 500-2000.

The hydrocracking catalyst prepared by the method has the cracking active centers distributed on the outer surface of the catalyst, the cracking reaction carried out on the catalyst is mainly carried out on the outer surface of the catalyst, and only the hydrogenation saturation reaction is carried out in the catalyst, so that the secondary cracking reaction can be greatly reduced under the condition of ensuring the hydrogenation saturation capacity of the catalyst. For the reaction process of producing the lubricating oil base oil by hydrocracking, reactant molecules firstly complete ring-opening reaction on the outer surface of the catalyst and then enter the interior of the catalyst for deep saturation, so that on one hand, the reduction of secondary cracking reaction can reduce the cracking of the high value-added lubricating oil base oil to generate other low-value products; on the other hand, the reduction of the secondary cracking reaction can reduce the excessive cracking of the high-viscosity index components of the straight-chain paraffin in the lubricating oil base oil, and enrich the high-viscosity index hydrocarbon components in unconverted oil.

Detailed Description

The following examples are given to further illustrate the effects and effects of the present invention, but the following examples are not intended to limit the process of the present invention.

Example 1

The preparation method of the molecular sieve comprises the following steps:

(1) mixing NaY molecular sieve raw powder prepared in a laboratory with ammonium nitrate with the concentration of 1.7mol/L according to the liquid-solid ratio of 10:1, exchanging for 1 hour at 80 ℃, repeating the process for 2 times, wherein the Na content in the exchanged Y molecular sieve is Na₂2.6 percent of O;

(2) carrying out hydrothermal treatment on the Y molecular sieve obtained in the step (1) at 620 ℃ and 0.1Mpa for 2 hours, and repeating the process twice;

(3) and (3) mixing the molecular sieve obtained in the step (2) with dilute nitric acid according to a liquid-solid ratio of 10:1 mixing (the concentration of dilute nitric acid in the solution is controlled to be 1mol/L by an H + ion concentration meter), and then heating to 90 ℃ for constant-temperature reaction for 3 hours.

(4) Mixing the Y molecular sieve treated by the dilute nitric acid solution in the step (3) with sodium nitrate with the concentration of 1.2mol/L according to the liquid-solid ratio of 10:1, exchanging for 2 hours at 70 ℃, and repeating the process for 2 times;

(5) performing sodium ion exchange on the acid-treated molecular sieve in the step (4), wherein the exchange condition is Na (NO)₃) Liquid-solid ratio of aqueous solution to molecular sieve of 6:1, Na (NO)₃) The concentration of the aqueous solution is 1.5mol/L (calculated by sodium ions), the exchange temperature is 60 ℃, and the exchange time is 3 h;

(6) and (4) drying the molecular sieve treated in the step (5) at 120 ℃ for 4h, and roasting at 550 ℃ for 2h to obtain the final modified molecular sieve Y-1.

The obtained molecular sieve SiO₂/Al₂O₃The molar ratio was 23. XRD analysis results show that the unit cell relative crystallinity is 83%. The pore volume is 0.43ml/g, the specific surface area is 712m2/g, and the sodium oxide content is 5.2 wt%.

The preparation method of the catalyst comprises the following steps:

(1) taking modified Y molecular sieve Y-1 and industrial alumina according to the mass ratio of 1: 9, mixing, rolling, extruding and forming, drying at 120 ℃ for 4h, and roasting at 550 ℃ for 3h to obtain a catalyst carrier with the number of T-1; (2) soaking the carrier T-1 in petroleum ether for 3h according to the liquid-solid ratio of 8:1, and then placing the carrier soaked in petroleum ether in a heater which is preheated to 130 ℃ in advance, wherein the drying time is 10 minutes. (3) Taking the dried sample in the step 2, mixing the dried sample with ammonium nitrate with the concentration of 1.0mol/L according to the liquid-solid ratio of 10:1, and exchanging for 1 hour at 90 ℃; (4) and (4) drying the carrier obtained in the step (3) at 120 ℃ for 4h, roasting at 500 ℃ for 4h, then impregnating the active metal by a supersaturation impregnation method, and then drying at 120 ℃ for 4h and roasting at 500 ℃ for 4h to obtain the final catalyst, wherein the number of the final catalyst is C-1.

Example 2

The preparation method of the molecular sieve comprises the following steps:

(1) mixing NaY molecular sieve raw powder prepared in a laboratory with ammonium nitrate with the concentration of 2mol/L according to the liquid-solid ratio of 10:1, exchanging for 1 hour at 60 ℃, repeating the process for 2 times, wherein the Na content in the exchanged Y molecular sieve is Na₂O is 2.5%;

(2) carrying out hydrothermal treatment on the Y molecular sieve obtained in the step (1) at 640 ℃ and 0.1Mpa for 2 hours, and repeating the process twice;

(3) and (3) mixing the molecular sieve obtained in the step (2) with dilute nitric acid according to a liquid-solid ratio of 10:1 mixing (controlling the concentration of dilute nitric acid in the solution to be 1.4mol/L by an H + ion concentration meter), and then heating to 90 ℃ for constant-temperature reaction for 2 hours.

(4) Mixing the Y molecular sieve treated by the dilute nitric acid solution in the step (3) with sodium nitrate with the concentration of 1.5mol/L according to the liquid-solid ratio of 10:1, exchanging for 1 hour at 70 ℃, and repeating the process for 2 times;

(5) performing sodium ion exchange on the acid-treated molecular sieve in the step (4)Alternatively, the exchange condition is Na (NO)₃) Liquid-solid ratio of aqueous solution to molecular sieve of 6:1, Na (NO)₃) The concentration of the aqueous solution is 1.2mol/L (calculated by sodium ions), the exchange temperature is 80 ℃, and the exchange time is 2 h;

(6) and (4) drying the molecular sieve treated in the step (5) at 120 ℃ for 4h, and roasting at 550 ℃ for 2h to obtain the final modified molecular sieve Y-2.

The obtained molecular sieve SiO₂/Al₂O₃The molar ratio was 38. XRD analysis results show that the unit cell relative crystallinity is 80%. The pore volume is 0.46ml/g, the specific surface area is 715m2/g, and the sodium oxide content is 3.3 wt%.

The preparation method of the catalyst comprises the following steps:

(1) taking modified Y molecular sieve Y-2 and industrial alumina according to the mass ratio of 1: 4, mixing, rolling, extruding and forming, drying at 120 ℃ for 4h, and roasting at 550 ℃ for 3h to obtain a catalyst carrier, which is numbered T-2; (2) soaking the carrier T-2 in n-heptane at a liquid-solid ratio of 8:1 for 4h, and drying in a heater at 100 deg.C for 15 min. (3) Taking the dried sample in the step 2, mixing the dried sample with ammonium nitrate with the concentration of 1.5mol/L according to the liquid-solid ratio of 10:1, and exchanging for 1 hour at 80 ℃; (4) and (4) drying the carrier obtained in the step (3) at 120 ℃ for 4h, roasting at 500 ℃ for 4h, impregnating the active metal according to a supersaturation impregnation method, drying at 120 ℃ for 4h, and roasting at 500 ℃ for 4h to obtain the final catalyst, wherein the number of the final catalyst is C-2.

Example 3

The preparation method of the molecular sieve comprises the following steps:

(1) mixing NaY molecular sieve raw powder prepared in a laboratory with ammonium nitrate with the concentration of 2mol/L according to the liquid-solid ratio of 10:1, exchanging for 1 hour at 80 ℃, repeating the process for 1 time, wherein the Na content in the exchanged Y molecular sieve is Na₂2.9 percent of O;

(2) carrying out hydrothermal treatment on the Y molecular sieve obtained in the step (1) at 660 ℃ and 0.1Mpa for 3 hours, and repeating the process for 1 time;

(3) and (3) mixing the molecular sieve obtained in the step (2) with dilute nitric acid according to a liquid-solid ratio of 10:1 mixing (controlling the concentration of dilute nitric acid in the solution to be 1.6mol/L by an H + ion concentration meter), and then heating to 70 ℃ for reacting for 2 hours at constant temperature.

(4) Mixing the Y molecular sieve treated by the dilute nitric acid solution in the step (3) with sodium nitrate with the concentration of 1.5mol/L according to the liquid-solid ratio of 10:1, exchanging for 1 hour at 70 ℃, and repeating the process for 2 times;

(5) performing sodium ion exchange on the acid-treated molecular sieve in the step (4), wherein the exchange condition is Na (NO)₃) Liquid-solid ratio of aqueous solution to molecular sieve of 6:1, Na (NO)₃) The concentration of the aqueous solution is 1.6mol/L (calculated by sodium ions), the exchange temperature is 60 ℃, and the exchange time is 2 h;

(6) and (4) drying the molecular sieve treated in the step (5) at 120 ℃ for 4h, and roasting at 550 ℃ for 2h to obtain the final modified molecular sieve Y-3.

The obtained molecular sieve SiO₂/Al₂O₃The molar ratio was 36. XRD analysis results show that the unit cell relative crystallinity is 82%. The pore volume is 0.44ml/g, the specific surface area is 722m2/g, and the sodium oxide content is 3.5 wt%.

The preparation method of the catalyst comprises the following steps:

(1) taking modified Y molecular sieve Y-3 and industrial alumina according to the mass ratio of 1: 2, mixing, rolling, extruding and forming, drying at 120 ℃ for 4h, and roasting at 550 ℃ for 3h to obtain a catalyst carrier, which is numbered T-3; (2) soaking the carrier T-3 in a toluene solution for 4h according to the liquid-solid ratio of 10:1, then placing the carrier soaked with petroleum ether in a heater which is preheated to 150 ℃ in advance, and drying for 8 minutes. (3) Taking the dried sample in the step 2, mixing the dried sample with ammonium nitrate with the concentration of 1.1mol/L according to the liquid-solid ratio of 10:1, and exchanging for 2 hours at 80 ℃; (4) and (4) drying the carrier obtained in the step (3) at 120 ℃ for 4h, roasting at 550 ℃ for 4h, impregnating the active metal according to an equal-volume impregnation method, drying at 120 ℃ for 4h, and roasting at 500 ℃ for 4h to obtain the final catalyst, wherein the number of the final catalyst is C-3.

Example 4

The preparation method of the molecular sieve comprises the following steps:

(1) mixing NaY molecular sieve raw powder prepared in a laboratory with ammonium nitrate with the concentration of 1.7mol/L according to the liquid-solid ratio of 10:1, exchanging for 1 hour at 80 ℃, repeating the process for 2 times, wherein the Na content in the exchanged Y molecular sieve is Na₂2.6 percent of O;

(2) carrying out hydrothermal treatment on the Y molecular sieve obtained in the step (1) at 640 ℃ and 0.1Mpa for 2 hours, and repeating the process twice;

(3) and (3) mixing the molecular sieve obtained in the step (2) with an ammonium fluosilicate aqueous solution according to a liquid-solid ratio of 10:1 (the concentration of ammonium fluosilicate is 1.3 mol/L), and then the temperature is raised to 90 ℃ for constant temperature reaction for 3 hours.

(4) Mixing the Y molecular sieve treated by the ammonium fluosilicate in the step (3) with sodium nitrate with the concentration of 1.1mol/L according to the liquid-solid ratio of 10:1, exchanging for 2 hours at 70 ℃, and repeating the process for 2 times;

(5) performing sodium ion exchange on the acid-treated molecular sieve in the step (4), wherein the exchange condition is Na (NO)₃) Liquid-solid ratio of aqueous solution to molecular sieve of 6:1, Na (NO)₃) The concentration of the aqueous solution is 1.5mol/L (calculated by sodium ions), the exchange temperature is 60 ℃, and the exchange time is 3 h;

(6) and (4) drying the molecular sieve treated in the step (5) at 120 ℃ for 4h, and roasting at 550 ℃ for 2h to obtain the final modified molecular sieve Y-4.

The obtained molecular sieve SiO₂/Al₂O₃The molar ratio was 26. XRD analysis results show that the unit cell relative crystallinity is 88%. Pore volume of 0.40ml/g and specific surface area of 735m²Per g, sodium oxide content 4.8 wt%.

The preparation method of the catalyst comprises the following steps:

(1) taking modified Y molecular sieve Y-4 and industrial alumina according to the mass ratio of 1: 9, mixing, rolling, extruding and forming, drying at 120 ℃ for 4h, and roasting at 550 ℃ for 3h to obtain a catalyst carrier with the number of T-1; (2) soaking the carrier T-1 in petroleum ether for 3h according to the liquid-solid ratio of 8:1, and then placing the carrier soaked in petroleum ether in a heater which is preheated to 130 ℃ in advance, wherein the drying time is 12 minutes. (3) Taking the dried sample in the step 2, mixing the dried sample with ammonium nitrate with the concentration of 1.0mol/L according to the liquid-solid ratio of 10:1, and exchanging for 1 hour at 90 ℃; (4) and (4) drying the carrier obtained in the step (3) at 120 ℃ for 4h, roasting at 500 ℃ for 4h, impregnating the active metal by adopting an isovolumetric impregnation method, drying at 120 ℃ for 4h, and roasting at 500 ℃ for 4h to obtain the final catalyst, wherein the number of the final catalyst is C-4.

Example 5

The preparation method of the molecular sieve comprises the following steps:

(1) mixing NaY molecular sieve raw powder prepared in a laboratory with ammonium nitrate with the concentration of 2mol/L according to the liquid-solid ratio of 10:1, exchanging for 1 hour at 80 ℃, repeating the process for 1 time, and exchangingNa content in the Y molecular sieve is Na₂2.9 percent of O;

(2) carrying out hydrothermal treatment on the Y molecular sieve obtained in the step (1) at 660 ℃ and 0.1Mpa for 3 hours, and repeating the process for 2 times;

(3) the molecular sieve obtained in the step (2) and an aluminum sulfate solution are mixed according to a liquid-solid ratio of 10:1 mixing (with Al)³⁺Controlling the concentration of dilute nitric acid in the solution to be 1.5mol/L by an ion concentration meter), and then heating to 90 ℃ for constant-temperature reaction for 2 hours.

(4) Mixing the Y molecular sieve treated by the aluminum sulfate solution in the step (3) with sodium nitrate with the concentration of 1.5mol/L according to the liquid-solid ratio of 10:1, exchanging for 1 hour at 70 ℃, and repeating the process for 2 times;

(5) performing sodium ion exchange on the acid-treated molecular sieve in the step (4), wherein the exchange condition is Na (NO)₃) Liquid-solid ratio of aqueous solution to molecular sieve of 6:1, Na (NO)₃) The concentration of the aqueous solution is 1.6mol/L (calculated by sodium ions), the exchange temperature is 60 ℃, and the exchange time is 2 h;

(6) and (4) drying the molecular sieve treated in the step (5) at 120 ℃ for 4h, and roasting at 550 ℃ for 2h to obtain the final modified molecular sieve Y-5.

The obtained molecular sieve SiO₂/Al₂O₃The molar ratio was 45. XRD analysis results show that the unit cell relative crystallinity is 80%. The pore volume is 0.48ml/g, the specific surface area is 684m2/g, and the sodium oxide content is 2.5 wt%.

The preparation method of the catalyst comprises the following steps:

(1) taking modified Y molecular sieve Y-3 and industrial alumina according to the mass ratio of 1: 2, mixing, rolling, extruding and forming, drying at 120 ℃ for 4h, and roasting at 550 ℃ for 3h to obtain a catalyst carrier, which is numbered T-3; (2) soaking the carrier T-3 in a toluene solution for 4h according to the liquid-solid ratio of 10:1, then placing the carrier soaked with petroleum ether in a heater which is preheated to 150 ℃ in advance, and drying for 8 minutes. (3) Taking the dried sample in the step 2, mixing the dried sample with ammonium nitrate with the concentration of 1.1mol/L according to the liquid-solid ratio of 10:1, and exchanging for 2 hours at 80 ℃; (4) and (4) drying the carrier obtained in the step (3) at 120 ℃ for 4h, roasting at 550 ℃ for 4h, then impregnating the active metal according to a conventional isometric impregnation method, drying at 120 ℃ for 4h, and roasting at 500 ℃ for 4h to obtain the final catalyst, wherein the number of the final catalyst is C-5.

Comparative examples 1 to 3 molecular sieve modification and catalyst preparation methods

Comparative example 1

The preparation method of the molecular sieve comprises the following steps:

(1) mixing NaY molecular sieve raw powder prepared in a laboratory with ammonium nitrate with the concentration of 1.7mol/L according to the liquid-solid ratio of 10:1, exchanging for 1 hour at 80 ℃, repeating the process for 2 times, wherein the Na content in the exchanged Y molecular sieve is Na₂2.6 percent of O;

(2) carrying out hydrothermal treatment on the Y molecular sieve obtained in the step (1) at 620 ℃ and 0.1Mpa for 2 hours, and repeating the process twice;

(3) and (3) mixing the molecular sieve obtained in the step (2) with dilute nitric acid according to a liquid-solid ratio of 10:1 mixing (the concentration of dilute nitric acid in the solution is controlled to be 1mol/L by an H + ion concentration meter), and then heating to 90 ℃ for constant-temperature reaction for 3 hours.

(4) And (4) drying the molecular sieve treated in the step (3) at 120 ℃ for 4h, and roasting at 550 ℃ for 2h to obtain the final modified molecular sieve BY-1.

The obtained molecular sieve SiO₂/Al₂O₃The molar ratio was 23. XRD analysis results show that the unit cell relative crystallinity is 83%. Pore volume 0.44ml/g, specific surface area 735m2/g, sodium oxide content 0.05 wt%.

The preparation method of the catalyst comprises the following steps:

(1) taking modified Y molecular sieve BY-1 and industrial alumina according to the mass ratio of 1: 9, mixing, rolling, extruding and forming, drying at 120 ℃ for 4h, and roasting at 550 ℃ for 3h to obtain a catalyst carrier numbered BT-1; (2) and (2) impregnating the carrier obtained in the step (1) with active metal according to a conventional impregnation method, drying at 120 ℃ for 4h, and roasting at 500 ℃ for 4h to obtain the final catalyst, wherein the number of the final catalyst is BC-1.

Comparative example 2

The preparation method of the molecular sieve comprises the following steps:

(1) mixing NaY molecular sieve raw powder prepared in a laboratory with ammonium nitrate with the concentration of 2mol/L according to the liquid-solid ratio of 10:1, exchanging for 1 hour at 60 ℃, repeating the process for 2 times, wherein the Na content in the exchanged Y molecular sieve is Na₂O is 2.5%;

(2) carrying out hydrothermal treatment on the Y molecular sieve obtained in the step (1) at 640 ℃ and 0.1Mpa for 2 hours, and repeating the process twice;

(3) and (3) mixing the molecular sieve obtained in the step (2) with dilute nitric acid according to a liquid-solid ratio of 10:1 mixing (controlling the concentration of dilute nitric acid in the solution to be 1.4mol/L by an H + ion concentration meter), and then heating to 90 ℃ for constant-temperature reaction for 2 hours.

(4) Mixing the Y molecular sieve treated by the dilute nitric acid solution in the step (3) with sodium nitrate with the concentration of 1.5mol/L according to the liquid-solid ratio of 10:1, exchanging for 1 hour at 70 ℃, and repeating the process for 2 times;

(4) and (4) drying the molecular sieve treated in the step (3) at 120 ℃ for 4h, and roasting at 550 ℃ for 2h to obtain the final modified molecular sieve BY-2.

The obtained molecular sieve SiO₂/Al₂O₃The molar ratio was 38. XRD analysis results show that the unit cell relative crystallinity is 80%. The pore volume is 0.47ml/g, the specific surface area is 722m2/g, and the sodium oxide content is 0.06 wt%.

The preparation method of the catalyst comprises the following steps:

(1) taking modified Y molecular sieve BY-2 and industrial alumina according to the mass ratio of 1: 4, mixing, rolling, extruding and forming, drying at 120 ℃ for 4h, and roasting at 550 ℃ for 3h to obtain a catalyst carrier numbered BT-2; (2) the active metal is impregnated in the step (1) according to a conventional impregnation method, and then the active metal is dried at 120 ℃ for 4 hours and roasted at 500 ℃ for 4 hours to obtain the final catalyst, wherein the number is BC-2.

Comparative example 3

The preparation method of the molecular sieve comprises the following steps:

(1) mixing NaY molecular sieve raw powder prepared in a laboratory with ammonium nitrate with the concentration of 2mol/L according to the liquid-solid ratio of 10:1, exchanging for 1 hour at 80 ℃, repeating the process for 1 time, wherein the Na content in the exchanged Y molecular sieve is Na₂2.9 percent of O;

(2) carrying out hydrothermal treatment on the Y molecular sieve obtained in the step (1) at 660 ℃ and 0.1Mpa for 3 hours, and repeating the process for 1 time;

(3) and (3) mixing the molecular sieve obtained in the step (2) with dilute nitric acid according to a liquid-solid ratio of 10:1 mixing (controlling the concentration of dilute nitric acid in the solution to be 1.6mol/L by an H + ion concentration meter), and then heating to 70 ℃ for reacting for 2 hours at constant temperature.

(4) And (4) drying the molecular sieve treated in the step (3) at 120 ℃ for 4h, and roasting at 550 ℃ for 2h to obtain the final modified molecular sieve BY-3.

The obtained molecular sieve SiO₂/Al₂O₃The molar ratio was 36. XRD analysis results show that the unit cell relative crystallinity is 82%. The pore volume is 0.46ml/g, the specific surface area is 732m2/g, and the sodium oxide content is 0.08 wt%.

The preparation method of the catalyst comprises the following steps:

(1) taking modified Y molecular sieve Y-3 and industrial alumina according to the mass ratio of 1: 2, mixing, rolling, extruding and forming, drying at 120 ℃ for 4h, and roasting at 550 ℃ for 3h to obtain a catalyst carrier numbered BT-3; (2) and (2) impregnating the carrier obtained in the step (1) with active metal according to a conventional impregnation method, drying at 120 ℃ for 4h, and roasting at 500 ℃ for 4h to obtain the final catalyst, wherein the number of the final catalyst is BC-3.

In order to examine the reaction performance of the catalysts prepared in examples 1 to 5 and comparative examples 1 to 3, the catalysts were subjected to an evaluation test on a small-scale apparatus, the evaluation apparatus employs a single-stage series process, the conventional refined catalyst was packed in one reaction, the catalysts prepared according to the methods of examples 1 to 3 and comparative examples 1 to 3 were packed in two reactions, and the analysis results and the evaluation results of the physicochemical properties of the catalysts are shown in tables 1 to 6.

TABLE 1 examples catalyst physico-chemical Properties

TABLE 2 results of analysis of physicochemical Properties of catalysts of comparative examples

TABLE 3 Properties of the feed oils

TABLE 4 operating conditions used in examples 1 to 3 and comparative examples 1 to 3

TABLE 5 evaluation results of examples 1 to 3 and comparative examples 1 to 3 (cutting scheme 1)

TABLE 6 evaluation results of examples 1 to 3 and comparative examples 1 to 3 (cutting scheme 2)