CN110833847B

CN110833847B - Hydrocracking catalyst, preparation method and application thereof

Info

Publication number: CN110833847B
Application number: CN201810935163.7A
Authority: CN
Inventors: 毛以朝; 龙湘云; 张润强; 赵阳; 赵广乐
Original assignee: Sinopec Research Institute of Petroleum Processing; China Petroleum and Chemical Corp
Current assignee: Sinopec Research Institute of Petroleum Processing; China Petroleum and Chemical Corp
Priority date: 2018-08-16
Filing date: 2018-08-16
Publication date: 2023-04-07
Anticipated expiration: 2038-08-16
Also published as: CN110833847A

Abstract

The present disclosure relates to a hydrocracking catalyst, a preparation method and an application thereof, wherein the catalyst comprises a carrier of 45-85 wt% calculated by dry weight of the catalyst, a first metal component of 5-40 wt% calculated by metal oxide, and a second metal component of 1-15 wt% calculated by metal oxide; the carrier comprises a phosphorus-containing Y-type molecular sieve, a Beta molecular sieve, weakly acidic silicon aluminum and a heat-resistant inorganic oxide, wherein the weight ratio of the phosphorus-containing Y-type molecular sieve to the Beta molecular sieve to the weakly acidic silicon aluminum to the heat-resistant inorganic oxide is (0.03-7): (0.03-7): (0.1-2.5): 1; the first metal is a metal selected from group VIB; the second metal component is a metal selected from group VIII; calculated by oxide, the phosphorus content of the phosphorus-containing Y-type molecular sieve is 0.3-5 wt%, the pore volume is 0.2-0.95 mL/g, and the ratio of pyridine infrared B acid to L acid is 2-10. The catalyst has higher hydrocracking reaction activity and cold flow property.

Description

Hydrocracking catalyst, preparation method and application thereof

Technical Field

The disclosure relates to a hydrocracking catalyst, a preparation method and an application thereof.

Background

The industrial hydrocracking feed comprises 350-540 ℃ fractions such as VGO and the like, the aromatic hydrocarbon content in heavy fractions is reduced, and the naphthenic hydrocarbon content is higher, so that the ring opening performance becomes an effective means for improving the tail oil quality and increasing the smoke point of aviation kerosene. However, since the beta bond in the cycloalkane is in the vertical direction of the empty p orbital of the cycloalkane carbonium ion, so that the two are not easily formed into a coplanar conformation, this makes the cycloalkane ring-opening require stronger acidity. The molecular sieve has high acidity and is widely applied to hydrocracking reaction. However, the common HY molecular sieve is unstable in structure, framework dealumination is easy to occur in the catalyst preparation and use processes, and non-framework aluminum generated in the molecular sieve preparation process is generally weak in acidity, so that a B acid center is shielded, and the catalyst performance is reduced. The molecular sieve structure can be stabilized by performing the ultra-stabilization treatment in the modes of hydrothermal treatment, introduction of a second component and the like. Wherein the introduction of the second component generally includes an olefinic component and a phosphorous component. Because P and non-framework aluminum removed from the molecular sieve form a phosphorus-aluminum oxide complex with larger molecular weight in the roasting process, the complex has higher thermal stability, is favorable for preventing framework dealumination, and can replace the function of rare earth components to a certain extent.

Patent CN1279130A discloses a method for preparing a phosphorus-containing Y-type molecular sieve, which comprises adding 0.5-5 wt% (as P) ₂ O ₅ Calculated) phosphorus, na ₂ P-NH with O content of 0.5-6 wt% and unit cell constant of 2.460-2.475 nm ₄ Carrying out hydrothermal roasting on the NaY molecular sieve for 0.5-4 hours at 450-700 ℃ in a roasting furnace in an atmosphere of 100% water vapor; carrying out liquid-phase aluminum extraction and silicon supplement reaction on the roasted product; then filtered and washed. The obtained phosphorus-containing ultrastable Y-type molecular sieve has good product selectivity, hydrothermal stability and good vanadium poisoning resistance, and when the cracking catalyst containing the molecular sieve is used for hydrocarbon cracking reaction, the yield of light oil is high, the yield of coke is low, the conversion capacity of heavy oil is high, and the olefin content in gasoline is low.

Patent ZL200410071122.6 discloses a containerA phosphorus molecular sieve containing 85 to 99.9 wt% of molecular sieve and P ₂ O ₅ 0.1 to 15% by weight of phosphorus, of said molecular sieve ³¹ In the P MAS-NMR spectrum, the percentage of the peak area of the peak with chemical shift of 0 +/-1.0 ppm in the total peak area is less than 1%. The preparation method of the molecular sieve comprises the steps of introducing phosphorus into the molecular sieve, and washing the molecular sieve by using an aqueous solution containing acid, wherein the acid is selected from one or more of water-soluble organic acid and inorganic acid, the content of the acid is 0.0001-10.0 mol/L, and the washing temperature is room temperature-95 ℃. The invention is characterized in that after the introduction of phosphorus, the method comprises a step of washing the molecular sieve by an acid solution, and the hydrocracking catalyst prepared by the phosphorus-containing molecular sieve has higher hydrocracking activity while maintaining high selectivity.

The prior art generally carries out post-treatment on the P-containing molecular sieve to further improve the stability and acidity of the molecular sieve. These post-treatment methods typically comprise heat treatment and acid treatment. The prior art generally post-treats phosphorus-containing molecular sieves to further improve the stability and acidity of the molecular sieves. These post-treatment methods typically comprise heat treatment and acid treatment. In general, the introduction mode of water in the hydrothermal treatment process comprises two modes, namely, water vapor is introduced in the roasting process, and the material is self-heated and roasted to release water. In the two modes, as the water vapor pressure is increased sharply along with the rise of the temperature, in order to enable the existing equipment to bear the requirement of the reaction pressure, an open system is usually adopted, so that the powder is continuously taken out of the system along with the water vapor in the hydrothermal process, the reaction system is in unsteady operation, the product quality is not high, and the obtained molecular sieve has certain open-loop activity but still cannot meet the actual requirement.

The Beta molecular sieve has a three-dimensional cross pore structure and has strong isomerization capability, so the component is usually adopted in the hydrocracking catalyst to reduce the condensation point of the raw material. The hydrocracking catalyst containing the Beta molecular sieve is adopted for hydrocracking, the freezing point of diesel oil in the product is lower, and the wide-cut low-freezing-point diesel oil can be produced.

Disclosure of Invention

The purpose of the present disclosure is to provide a hydrocracking catalyst, a preparation method and an application thereof, wherein the hydrocracking catalyst has high hydrocracking reaction activity and cold flow performance.

To achieve the above object, a first aspect of the present disclosure: providing a hydrocracking catalyst comprising, on a dry basis, 45 to 85 wt% of a support, 5 to 40 wt% of a first metal component, calculated as the metal oxide, and 1 to 15 wt% of a second metal component, calculated as the metal oxide, based on the dry weight of the catalyst;

the carrier comprises a phosphorus-containing Y-type molecular sieve, a Beta molecular sieve, weakly acidic silicon aluminum and a heat-resistant inorganic oxide, wherein the weight ratio of the phosphorus-containing Y-type molecular sieve to the Beta molecular sieve to the weakly acidic silicon aluminum to the heat-resistant inorganic oxide is (0.03-7): (0.03-7): (0.1-2.5): 1; the first metal is a metal selected from group VIB; the second metal component is a metal selected from group VIII;

calculated by oxide, the phosphorus content of the phosphorus-containing Y-type molecular sieve is 0.3-5 wt%, the pore volume is 0.2-0.95 mL/g, and the ratio of pyridine infrared B acid to L acid is 2-10.

Optionally, the catalyst comprises 60 to 80 wt% of a carrier, 10 to 35 wt% of a first metal component, calculated as the metal oxide, and 2 to 10 wt% of a second metal component, calculated as the metal oxide, calculated as the dry weight of the catalyst;

the weight ratio of the phosphorus-containing Y-type molecular sieve to the Beta molecular sieve to the weakly acidic silicon-aluminum to the heat-resistant inorganic oxide is (0.5-6): (0.3-4): (0.8-2): 1.

optionally, of said phosphorus-containing Y-type molecular sieve ²⁷ In Al-NMR structural spectrum, I _60ppm /I _-1ppm Is 5 to 40 _-1ppm /I _±6ppm Is 0.4 to 2.

Optionally, the phosphorus-containing Y-type molecular sieve is prepared by a method comprising the following steps:

a. carrying out hydro-thermal treatment on a phosphorus-containing molecular sieve raw material for 0.5-10h at the temperature of 350-700 ℃ and the pressure of 0.1-2MPa in the presence of water vapor to obtain a hydro-thermally treated molecular sieve material; calculated by oxide and based on the dry basis weight of the phosphorus-containing molecular sieve raw material, the phosphorus content of the phosphorus-containing molecular sieve raw material is 0.1-15 weight percent, and the sodium content is 0.5-4.5 weight percent;

b. b, adding water into the molecular sieve material subjected to the hydrothermal treatment obtained in the step a for pulping to obtain molecular sieve slurry, heating the molecular sieve slurry to 40-95 ℃, then keeping the temperature, and continuously adding an acid solution into the molecular sieve slurry, wherein the weight of the acid in the acid solution is (0.01-0.6) relative to the dry weight of the phosphorus-containing molecular sieve raw material: 1, based on 1L of the molecular sieve slurry, taking H as reference ⁺ And (3) the adding speed of the acid solution is 0.05-10 mol/h, the constant temperature reaction is carried out for 0.5-20h after the acid is added, and a solid product is collected.

Optionally, in step a, the phosphorus-containing molecular sieve is a phosphorus-containing Y-type molecular sieve, the unit cell constant of the phosphorus-containing Y-type molecular sieve is 2.425-2.47 nm, and the specific surface area is 250-750 m ² The pore volume is 0.2-0.95 ml/g.

Optionally, in step a, the water content of the phosphorus-containing molecular sieve raw material is 10 to 40 wt%;

the phosphorus-containing molecular sieve raw material is granular, the content of the phosphorus-containing molecular sieve raw material with the granularity range of 1 mm-500 mm is 10-100 wt% of the total weight of the phosphorus-containing molecular sieve raw material, and the granularity is calculated by the diameter of a circumscribed circle of the granules.

Optionally, the content of the phosphorus-containing molecular sieve raw material with the particle size range of 1 mm-500 mm is 30-100 wt% of the total weight of the phosphorus-containing molecular sieve raw material;

preferably, the content of the phosphorus-containing molecular sieve raw material with the particle size ranging from 5mm to 100mm is 30 to 100 weight percent of the total weight of the phosphorus-containing molecular sieve raw material.

Optionally, in step b, the ratio of the weight of water in the molecular sieve slurry obtained after pulping to the dry weight of the phosphorus-containing molecular sieve raw material is (14-5): 1.

optionally, the preparation step of the phosphorus-containing Y-type molecular sieve further comprises: in the step b, adding ammonium salt into the molecular sieve slurry in the process of adding an acid solution, wherein the ammonium salt is ammonium nitrate, ammonium chloride or ammonium sulfate, or the combination of two or three of the ammonium nitrate, the ammonium chloride or the ammonium sulfate; the weight of the ammonium salt and the dry basis weight of the phosphorus-containing molecular sieve raw material are in a ratio of (0.1-2.0): 1.

optionally, in step b, the acid concentration of the acid solution is 0.01 to 15.0mol/L, and the acid is phosphoric acid, sulfuric acid, nitric acid, hydrochloric acid, acetic acid, citric acid, tartaric acid, formic acid or acetic acid, or a combination of two or three of them.

Optionally, the preparation step of the phosphorus-containing Y-type molecular sieve further comprises: collecting the solid product, then washing with water and drying to obtain a phosphorus-containing molecular sieve; the drying conditions are as follows: the temperature is 50-350 ℃, and the optimal temperature is 70-200 ℃; the time is 1 to 24 hours, preferably 2 to 6 hours.

Optionally, the framework Si/Al ratio of the Beta molecular sieve is 20-120, and the specific surface area is 200-650 m ² The pore volume is 0.20-0.75 mL/g;

the acidity value of the infrared B acid of the weakly acidic silicon aluminum is 0.01-0.1 mmol/g, the silicon content is 20-60 wt% calculated by silicon dioxide, and the pore volume is 0.45-0.95 mL/g; the weakly acidic silicon-aluminum is silicon-containing aluminum oxide and/or amorphous silicon-aluminum.

Optionally, the heat-resistant inorganic oxide is alumina, zirconia, magnesia, thoria, beryllia, boria or cadmium oxide, or a mixture of two or three of them; the first metal component is molybdenum and/or tungsten; the second metal component is at least one of iron, nickel or cobalt, or a mixture of two or three of them.

In a second aspect of the present disclosure: there is provided a process for preparing a hydrocracking catalyst according to the first aspect of the present disclosure, the process comprising: the impregnation liquid containing the metal precursor is contacted with the carrier for impregnation, and then the material obtained after the impregnation is dried.

Optionally, the method further comprises: mixing a phosphorus-containing Y-type molecular sieve, a Beta molecular sieve, weakly acidic silicon aluminum, a heat-resistant inorganic oxide, a peptizing agent and an optional lubricant, and then molding, drying and roasting to obtain the carrier.

Optionally, the metal precursor comprises a first metal precursor and a second metal precursor, wherein the first metal precursor is an inorganic acid of a first metal, an inorganic salt of a first metal, or a first metal organic compound, or a combination of two or three of them; the inorganic salt is nitrate, carbonate, basic carbonate, hypophosphite, phosphate, sulfate or chloride; the organic substituent in the first metal organic compound is hydroxyl, carboxyl, amino, ketone, ether or alkyl, or the combination of two or three of the hydroxyl, carboxyl, amino, ketone, ether or alkyl;

the second metal precursor is selected from inorganic acid of a second metal, inorganic salt of the second metal or a second metal organic compound, or a combination of two or three of the inorganic acid, the inorganic salt and the second metal; the inorganic salt is nitrate, carbonate, basic carbonate, hypophosphite, phosphate, sulfate or chloride; the organic substituent in the second metal organic compound is hydroxyl, carboxyl, amino, ketone, ether or alkyl, or the combination of two or three of the hydroxyl, carboxyl, amino, ketone, ether or alkyl.

Optionally, the impregnation liquid further contains an organic additive; the concentration of the organic additive is 2-300g/L; the organic additive is ethylene glycol, glycerol, polyethylene glycol, diethylene glycol, butanediol, acetic acid, maleic acid, oxalic acid, nitrilotriacetic acid, 1, 2-cyclohexanediaminetetraacetic acid, citric acid, tartaric acid, malic acid, ethylenediamine, diethylenetriamine, cyclohexanediaminetetraacetic acid, aminoacetic acid, nitrilotriacetic acid, ethylenediaminetetraacetic acid or ammonium ethylenediaminetetraacetate, or a combination of two or three thereof.

Optionally, the drying conditions are: the temperature is 80-350 ℃, and the time is 0.5-24 hours.

Optionally, the method further comprises a step of drying the contacted material and then roasting, wherein roasting conditions are as follows: the temperature is 350-600 ℃, and the time is 0.2-12 hours.

A third aspect of the disclosure: there is provided the use of a hydrocracking catalyst according to the first aspect of the disclosure in the hydrocracking reaction of a hydrocarbon feedstock.

Optionally, the hydrocarbon feedstock is selected from straight run gas oil, vacuum gas oil, demetallized oil, atmospheric residue, deasphalted vacuum residue, coker distillate, catalytically cracked distillate, shale oil, tar sand oil, or coal liquefaction oil;

the conditions of the hydrocracking reaction are as follows: the reaction temperature is 200-650 ℃, preferably 300-510 ℃; the reaction pressure is 3-24MPa, preferably 4-15 MPa; the liquid hourly space velocity is 0.1-10 hours ^-1 Preferably 0.2 to 5 hours ^-1 (ii) a The volume ratio of hydrogen to oil is 100-5000, preferably 200-1000.

According to the technical scheme, the phosphorus-containing molecular sieve raw material is subjected to special hydrothermal treatment and acid washing treatment to prepare the phosphorus-containing molecular sieve with excellent performance, the ratio of the acid content of B to the acid content of L is further improved, and a hydrocracking catalyst prepared from the phosphorus-containing molecular sieve has higher hydrocracking activity and ring opening selectivity; in addition, the Beta molecular sieve is added into the carrier of the catalyst disclosed by the invention, so that the cold flow property of the catalyst can be effectively improved.

Additional features and advantages of the disclosure will be set forth in the detailed description which follows.

Drawings

The accompanying drawings, which are included to provide a further understanding of the disclosure and are incorporated in and constitute a part of this specification, illustrate embodiments of the disclosure and together with the description serve to explain the disclosure, but do not constitute a limitation of the disclosure. In the drawings:

FIG. 1 is a schematic diagram of the preparation of molecular sieves prepared in examples 1-3 and comparative examples 1-4 ²⁷ Al-NMR structural spectrum.

Detailed Description

The following detailed description of the embodiments of the disclosure refers to the accompanying drawings. It should be understood that the detailed description and specific examples, while indicating the present disclosure, are given by way of illustration and explanation only, not limitation.

The first aspect of the disclosure: providing a hydrocracking catalyst comprising, on a dry basis, 45 to 85 wt% of a support, 5 to 40 wt% of a first metal component, calculated as the metal oxide, and 1 to 15 wt% of a second metal component, calculated as the metal oxide, based on the dry weight of the catalyst; preferably, the catalyst comprises 60 to 80 wt% of the support, 10 to 35 wt% of the first metal component, and 2 to 10 wt% of the second metal component, on a dry basis, based on the weight of the catalyst on a dry basis, on a metal oxide basis. The carrier comprises a phosphorus-containing Y-type molecular sieve, a Beta molecular sieve, weakly acidic silicon aluminum and a heat-resistant inorganic oxide, wherein the weight ratio of the phosphorus-containing Y-type molecular sieve to the Beta molecular sieve to the weakly acidic silicon aluminum to the heat-resistant inorganic oxide is (0.03-7): (0.03-7): (0.1-2.5): 1; preferably (0.5 to 6): (0.3-4): (0.8-2): 1. the first metal is a metal selected from group VIB; the second metal component is a metal selected from group VIII;

in the hydrocracking catalyst disclosed by the disclosure, the phosphorus-containing Y-type molecular sieve as one of the carrier components has special performance, so that the hydrocracking catalyst has higher hydrocracking activity and ring-opening selectivity. Calculated by oxide, the phosphorus content of the phosphorus-containing Y-type molecular sieve is 0.3-5 wt%, the pore volume is 0.2-0.95 mL/g, and the ratio of pyridine infrared B acid to L acid is 2-10.

The phosphorus-containing Y-type molecular sieve has a higher ratio of the B acid content to the L acid content. Particularly, the phosphorus-containing Y-type molecular sieve not only retains a higher ratio of framework aluminum to non-framework aluminum, but also retains certain non-framework aluminum at the position of the non-framework aluminum, namely the position of-4 to-6 ppm or the position of 3 to 7 ppm. In particular, of said molecular sieves ²⁷ In the Al-NMR structural spectrum, the peak height ratio of framework aluminum to non-framework aluminum, i.e. I, is 60 +/-1 ppm and-1 +/-1 ppm _60ppm /I _-1ppm Is 5 to 40; and the chemical shift position of 0ppm of non-framework aluminum has two obvious characteristic peaks: -1. + -. 1ppm, and-5.5. + -. 2ppm or 3-7 ppm, the peak height ratio of the two being I _-1ppm /I _±6ppm Is 0.4 to 2, preferably 0.8 to 2, wherein I _±6ppm The larger peak height of-5.5 +/-2 ppm and 3-7 ppm is taken.

The phosphorus-containing Y-type molecular sieve is prepared by carrying out special hydrothermal treatment and acid washing treatment on a phosphorus-containing molecular sieve raw material. Specifically, the phosphorus-containing Y-type molecular sieve is prepared by a method comprising the following steps:

a. carrying out hydro-thermal treatment on a phosphorus-containing molecular sieve raw material for 0.5-10h at the temperature of 350-700 ℃ and the pressure of 0.1-2MPa in the presence of water vapor to obtain a hydro-thermally treated molecular sieve material; calculated by oxide and based on the dry weight of the phosphorus-containing molecular sieve raw material, the phosphorus content of the phosphorus-containing molecular sieve raw material is 0.1-15 wt%, and the sodium content is 0.5-4.5 wt%;

According to the present disclosure, in step a, the phosphorus-containing molecular sieve raw material refers to a phosphorus-containing molecular sieve. By adopting the phosphorus-containing molecular sieve as a raw material, the phosphorus-aluminum species outside the molecular sieve framework can improve the framework stability of the molecular sieve, thereby further improving the performance of the molecular sieve. The structure of the phosphorus-containing molecular sieve raw material can be an octahedral zeolite molecular sieve structure, preferably a phosphorus-containing Y-type molecular sieve, the unit cell constant of the phosphorus-containing molecular sieve raw material can be 2.425-2.47 nm, and the specific surface area of the phosphorus-containing molecular sieve raw material can be 250-750 m ² The pore volume can be 0.2-0.95 ml/g. Further, the specific selection of the Y-type molecular sieve may be varied within a wide range as long as the phosphorus-containing molecular sieve raw material satisfies the above conditions, for example, the Y-type molecular sieve may be NaY, HNaY (hydrogen Y-type molecular sieve), REY (rare earth Y-type molecular sieve), USY (ultra stable Y-type molecular sieve), or the like. The cation position of the phosphorus-containing Y-type molecular sieve can be occupied by one or more of sodium ions, ammonium ions and hydrogen ions; alternatively, the sodium, ammonium, and hydrogen ions may be replaced by other ions, either before or after the molecular sieve is introduced with phosphorus, by conventional ion exchange. The phosphorus-containing molecular sieve starting material may be commercially available or may be prepared by any conventional technique, for example, byThe method for preparing USY disclosed in patent ZL00123139.1 or the method for preparing PUSY disclosed in patent ZL200410071122.6 and the like are adopted, and the details of the disclosure are not repeated.

According to the present disclosure, in step a, the water content of the phosphorus-containing molecular sieve raw material is preferably 10 to 40 wt%. The phosphorus-containing molecular sieve raw material with the water content can be obtained by adding water into the molecular sieve, pulping, filtering and drying. The phosphorus-containing molecular sieve raw material is preferably in a granular form, and the content of the phosphorus-containing molecular sieve raw material having a particle size range of 1mm to 500mm may be 10 to 100 wt%, preferably 30 to 100 wt%, based on the total weight of the phosphorus-containing molecular sieve raw material. Further, the content of the phosphorus-containing molecular sieve raw material with the granularity range of 5 mm-100 mm is 30-100 wt% of the total weight of the phosphorus-containing molecular sieve raw material. Wherein the particle size is in terms of the diameter of the circumscribed circle of particles. The phosphorus-containing molecular sieve raw material with the particle size range is adopted for hydrothermal treatment, so that the mass transfer effect of the hydrothermal treatment can be obviously improved, the material loss is reduced, and the operation stability is improved. The particle size control method of the molecular sieve raw material can be conventional in the field, such as a sieving method, an extrusion strip method, a rolling ball method and the like.

According to the present disclosure, the meaning of the water-adding beating in the step b is well known to those skilled in the art, and the ratio of the weight of water in the molecular sieve slurry obtained after beating to the dry weight of the phosphorus-containing molecular sieve raw material can be (14-5): 1.

according to the present disclosure, in step b, the molecular sieve slurry is preferably heated to 50 to 85 ℃, and then the temperature is maintained and the acid solution is continuously added to the molecular sieve slurry until the weight of the acid in the added acid solution reaches a set amount. The most important of the preparation steps of the phosphorus-containing Y-type molecular sieve is that a continuous acid adding mode is adopted, acid adding and acid washing reaction are carried out simultaneously, the acid adding speed is low, the dealumination process is more moderate, and the improvement of the performance of the molecular sieve is facilitated.

According to the present disclosure, the acid solution may be continuously added to the molecular sieve slurry at one time, that is, the whole acid solution is continuously added according to a specific acid adding speed, and then the reaction is performed at constant temperature. In particular, the acid solution may also be added in multiple portions in order to increase the utilization of the material and reduce the waste output. For example, the acid solution can be added to the molecular sieve slurry at a specific acid addition rate of 2-10 times, and after each acid addition, the reaction can be carried out at constant temperature for a period of time to continue the next acid addition until the set amount of the acid solution is added. When the acid solution is added in multiple portions, the ratio of the weight of acid in the acid solution to the dry weight of the phosphorus-containing molecular sieve starting material is preferably (0.01-0.3): 1. the acid concentration of the acid solution can be 0.01-15.0 mol/L, and the pH value can be 0.01-3. The acid may be a conventional inorganic and/or organic acid, for example, it may be phosphoric acid, sulphuric acid, nitric acid, hydrochloric acid, acetic acid, citric acid, tartaric acid, formic acid or acetic acid, or a combination of two or three of these.

According to the present disclosure, the preparation step of the phosphorus-containing Y-type molecular sieve may further include: in the step b, adding an ammonium salt into the molecular sieve slurry during the adding of the acid solution, wherein the ammonium salt can be at least one selected from ammonium nitrate, ammonium chloride and ammonium sulfate, and the weight ratio of the ammonium salt to the dry weight of the phosphorus-containing molecular sieve raw material can be (0.1-2.0): 1. the ammonium salt may be added to the molecular sieve slurry independently of the acid solution, or an aqueous solution containing the ammonium salt and the acid may be prepared in a desired amount and added to the molecular sieve slurry.

According to the present disclosure, the preparation step of the phosphorus-containing Y-type molecular sieve may further include: and collecting the solid product, and then washing and drying to obtain the phosphorus-containing Y-type molecular sieve. The washing and drying are conventional steps for preparing the molecular sieve, and the disclosure is not particularly limited. For example, the drying may be performed by using an oven, a mesh belt, a converter, or the like, and the drying conditions may be: the temperature is 50-350 ℃, and the optimal temperature is 70-200 ℃; the time is 1 to 24 hours, preferably 2 to 6 hours.

The Beta molecular sieves are well known to those skilled in the art in light of this disclosure, and their composition and structure are described in U.S. Pat. No. 3,308,069. Suitable Beta molecular sieves of the present disclosure are either commercially available or may be prepared using any of the techniques known in the art. Preferred Beta fractionsThe sub-sieves are Beta molecular sieves having a framework silica to alumina ratio (molar ratio) of at least 25, such as 30 to 500, and more preferably a framework silica to alumina ratio (molar ratio) of 30 to 200, as described in EP164,939, U.S. Pat. No. 4,923,690, U.S. Pat. No. 5,164,169, CN1108213A, CN1108214A, CN1086792A, and the like. Further preferably, the framework silicon-aluminum ratio of the Beta molecular sieve is 20-120, and the specific surface area is 200-650 m ² The pore volume is 0.20-0.75 mL/g. The hydrocracking catalyst disclosed by the invention adopts Beta as one of the carrier components, and when the catalyst is used in a hydrocracking reaction, the condensation point of a raw material can be reduced, and the cold flow performance of the catalyst is effectively improved.

According to the present disclosure, the weakly acidic silicon aluminum may have a specific surface area of 350 to 750m ² A silicon-aluminum material with the pore volume of 0.4 to 1.2mL/g and the infrared B acid acidity value of less than 0.1mmol/g, and the specific surface area of 400 to 650m is further preferred ² The concentration of the weak acid silicon aluminum is 0.45-0.95 mL/g, the pore volume is 0.45-0.95 mL/g, and the acidity value of the infrared B is 0.01-0.1 mmol/g. The silicon content, based on the weakly acidic silicon-aluminum, and calculated as silicon dioxide, may be 10 to 80% by weight, preferably 20 to 60% by weight. The weakly acidic silicon aluminum is, for example, silicon-containing alumina and/or amorphous silicon aluminum. The present disclosure does not specifically limit the source of the weakly acidic silica-alumina, may be commercially available or prepared using any of the prior art techniques.

According to the present disclosure, the heat-resistant inorganic oxide can increase the strength of the catalyst and improve and adjust physicochemical properties of the catalyst, such as improving the pore structure of the catalyst. The heat-resistant inorganic oxide may be an inorganic oxide commonly used for a hydrogenation catalyst carrier, such as alumina, silica, zirconia, magnesia, thoria, beryllia, boria or cadmium oxide, or a mixture of two or three of them. In a preferred embodiment of the present disclosure, the heat-resistant inorganic oxide is preferably alumina, and the alumina may include gibbsite such as gibbsite (gibbsite), bayerite nordstrandite (bayerite nordstrandandite) and diaspore such as boehmite (boehmite, diasporic, pseudoboehmite). In other embodiments, the refractory inorganic oxide is of another species or combination.

According to the present disclosure, preferably, the first metal component is molybdenum and/or tungsten; the second metal component is iron, nickel or cobalt, or a mixture of two or three of them.

A second aspect of the disclosure: there is provided a process for preparing a hydrocracking catalyst according to the first aspect of the present disclosure, the process comprising: the impregnation liquid containing the metal precursor is contacted with the carrier for impregnation, and then the material obtained after impregnation is dried. The contact impregnation method of the impregnation liquid and the carrier can adopt any one of the methods known in the art, for example, the method disclosed in patent CN200810241082.3, which comprises loading a group VIB metal component, a group VIII metal component and an organic additive on a catalyst carrier, wherein the loading of the group VIB metal component, the group VIII metal component and the organic additive on the catalyst carrier is any one of the following methods:

mode 1: contacting the catalyst carrier with a first solution, then contacting with a second solution, or contacting the catalyst carrier with a second solution, then contacting with the first solution, wherein the first solution contains a compound of a group VIB metal component and a compound of a group VIII metal component, the second solution contains a compound of a group VIB metal component but does not contain a compound of a group VIII metal component, and the first solution and/or the second solution contain the organic additive;

mode 2: contacting the catalyst carrier with a third solution and then with a fourth solution, or contacting the catalyst carrier with a fourth solution and then with a third solution, wherein the third solution contains a compound of a group VIB metal component, the fourth solution contains a compound of a group VIII metal component and an organic auxiliary agent but does not contain the compound of the group VIB metal component, and the third solution contains or does not contain the compound of the group VIII metal component and the organic additive,

wherein, after each contacting, the contacted catalyst support is heated.

Methods for preparing such carriers are well known to those skilled in the art, and the present disclosure is not particularly limited. For example, the method may further comprise: mixing a phosphorus-containing Y-type molecular sieve, a Beta molecular sieve, weakly acidic silicon aluminum, a heat-resistant inorganic oxide, a solvent and an optional auxiliary agent, and then molding and drying to obtain the carrier. The molding method can adopt various conventional methods, such as tabletting molding, rolling ball molding or extrusion molding. The solvent is a common solvent in the catalyst forming process. When the extrusion molding method is employed, an appropriate amount of an auxiliary is preferably added to facilitate molding.

Optionally, the preparation method of the carrier comprises: mixing a phosphorus-containing Y-type molecular sieve, a Beta molecular sieve, weakly acidic silicon aluminum, a heat-resistant inorganic oxide, a peptizing agent and an optional lubricant, and then molding, drying and roasting to obtain the carrier. The peptizing agent can be an acid-containing solution or a base-containing solution, the acid being selected from organic or inorganic acids familiar to those skilled in the art, such as phosphoric acid, sulfuric acid, nitric acid, hydrochloric acid, acetic acid, citric acid, tartaric acid, formic acid or acetic acid, or a combination of two or three thereof; cations such as ammonium, iron, cobalt, nickel, aluminum and the like which can keep the acid solution acidic can be added into the acid-containing solution; the alkali-containing solution comprises ammonia, an organic amine or urea, or a combination of two or three thereof.

The shape of the carrier is not particularly required in the present disclosure, and may be a sphere, a strip, a hollow strip, a sphere, a block, or the like, and the strip-shaped carrier may be a clover, or the like, and modifications thereof.

In an alternative embodiment of the present disclosure, the support may be prepared as disclosed in patent CN107029779A, specifically: (1) Mixing a phosphorus-containing Y-type molecular sieve, a Beta molecular sieve, weakly acidic silicon aluminum, a heat-resistant inorganic oxide, a peptizing agent, a lubricant and water to obtain a mixture, wherein the dosage of each component is that the weight ratio of the peptizing agent in the mixture to the powder is 0.28 multiplied by 10 ^-4 ～4.8×10 ^-4 mol/g, the ratio of the weight of water to the amount of mass of peptizing agent is 2.0X 10 ³ ～30×10 ³ g/mol, the weight of the powder is the sum of the weight of the phosphorus-containing Y-type molecular sieve, the weight of the Beta molecular sieve, the weight of the weak acid silicon aluminum and the weight of the heat-resistant inorganic oxide, and the peptizing agent substanceThe amount of (d) refers to the number of moles of H protons metered into the peptizing agent; the lubricant is one or two of sesbania powder and graphite; (2) And (2) kneading, molding, drying and roasting the mixture obtained in the step (1) to obtain the carrier.

According to the present disclosure, the metal precursors include a first metal precursor and a second metal precursor. Wherein the first metal precursor may be a soluble compound containing the first metal component, including an inorganic acid, an inorganic salt, or an organic compound of the first metal, or a combination of two or three thereof; the inorganic salt can be nitrate, carbonate, basic carbonate, hypophosphite, phosphate, sulfate or chloride; the organic substituent in the first metal organic compound may be a hydroxyl group, a carboxyl group, an amine group, a ketone group, an ether group, or an alkyl group, or a combination of two or three thereof. For example, when the first metal component is molybdenum, the first metal precursor may be selected from molybdic acid, paramolybdic acid, molybdate, or paramolybdate, or a combination of two or three thereof; when the first metal is tungsten, the first metal precursor may be tungstic acid, metatungstic acid, ethyl metatungstic acid, tungstate, metatungstate, or ethyl metatungstate, or a combination of two or three of them. The second metal precursor may be a soluble compound containing the second metal component, including an inorganic acid, inorganic salt, or organic compound of the second metal, or a combination of two or three thereof; the inorganic salt can be nitrate, carbonate, basic carbonate, hypophosphite, phosphate, sulfate or chloride; the organic substituent in the second metal organic compound may be a hydroxyl group, a carboxyl group, an amine group, a ketone group, an ether group, or an alkyl group, or a combination of two or three thereof.

According to the present disclosure, the impregnation fluid may further contain an organic additive; the concentration of the organic additive may be 2 to 300g/L. The organic additive is an oxygen-containing organic compound and/or a nitrogen-containing organic compound. Specifically, the oxygen-containing organic compound may be ethylene glycol, glycerol, polyethylene glycol (molecular weight may be 200 to 1500), diethylene glycol, butanediol, acetic acid, maleic acid, oxalic acid, nitrilotriacetic acid, 1, 2-cyclohexanediaminetetraacetic acid, citric acid, tartaric acid, or malic acid, or a combination of two or three thereof; the nitrogen-containing organic compound may be ethylenediamine, diethylenetriamine, cyclohexanediaminetetraacetic acid, glycine, nitrilotriacetic acid, ethylenediaminetetraacetic acid or ammonium ethylenediaminetetraacetate, or a combination of two or three thereof.

In the method for producing a hydrocracking catalyst of the present disclosure, the contacting temperature is not particularly limited, and may be various temperatures that the impregnation solution can reach. The time for the impregnation is also not particularly limited as long as the catalyst carrier can be supported with the desired amount of the metal active component precursor. In general, the higher the impregnation temperature, the higher the concentration of the impregnation solution, and the shorter the time required to achieve the same impregnation amount (i.e., the weight difference between the catalyst support after impregnation and the catalyst support before impregnation); and vice versa. When the desired amount and conditions of impregnation are determined, one skilled in the art can readily select an appropriate impregnation time based on the teachings of the present disclosure. The present disclosure does not specifically require an impregnation method, which may be either a saturated impregnation or a supersaturated impregnation. The impregnation may be carried out under a sealed condition or in an open environment according to a conventional method in the art, and the loss of the aqueous solvent may or may not be replenished during the impregnation. Various gases, such as air, nitrogen, water vapor, etc., may be introduced during the impregnation process, or any new components may not be introduced.

In the method for preparing a hydrocracking catalyst according to the present disclosure, the drying conditions are not particularly limited, and may be various drying conditions commonly used in the art, for example: the temperature is 80-350 deg.C, preferably 100-300 deg.C, and the time is 0.5-24 hr, preferably 1-12 hr.

The method for preparing a hydrocracking catalyst according to the present disclosure may further include a step of drying the contacted material and then calcining, which is a conventional step for preparing a catalyst, and the present disclosure is not particularly limited. The conditions for the calcination may be, for example: the temperature is 350-600 ℃, preferably 400-550 ℃; the time is 0.2 to 12 hours, preferably 1 to 10 hours.

The hydrocracking catalyst provided by the disclosure can be used as various acid catalytic catalysts in catalytic cracking, hydroisomerization, alkylation, hydrocracking and other reactions, and is particularly suitable for hydrocracking hydrocarbon raw materials to produce hydrocarbon fractions with lower boiling points and lower molecular weights. Accordingly, a third aspect of the disclosure: there is provided the use of a hydrocracking catalyst according to the first aspect of the present disclosure in a hydrocracking reaction of a hydrocarbon feedstock.

The hydrocarbon feedstock may be various heavy mineral oils or synthetic oils or their mixed distillates, such as straight run gas oil (straight run gas oil), vacuum gas oil (vacuum gas oil), demetalized oils (demetalized oils), atmospheric residues (atmospheric residues), deasphalted vacuum residues (deasphalted vacuum residues), coker distillates (coker distillates), catalytic cracker distillates (cat distillates), shale oils (shell oils), tar sand oils (tar sand oils), coal liquefied oils (coal liquids), etc. In particular, the catalyst provided by the present disclosure is particularly suitable for hydrocracking heavy and poor distillate to produce a hydrocracking process of middle distillate with a distillation range of 149-371 ℃, especially a distillation range of 180-370 ℃.

The application of the hydrocracking catalyst provided by the present disclosure in the hydrocracking reaction of hydrocarbon raw materials preferably further comprises the step of pre-sulfurizing the hydrocracking catalyst with sulfur, hydrogen sulfide or sulfur-containing raw materials at the temperature of 140-370 ℃ in the presence of hydrogen before using the hydrocracking catalyst, wherein the pre-sulfurization can be carried out outside a reactor or in-situ in the reactor, and the pre-sulfurization can be carried out to convert the hydrocracking catalyst into a sulfide type.

The catalyst provided by the present disclosure can be used under conventional hydrocracking process conditions when used for distillate oil hydrocracking, for example, the hydrocracking reaction conditions are as follows: the reaction temperature is 200-650 ℃, the preference is 300-510 ℃, the reaction pressure is 3-24MPa, the preference is 4-15MPa, and the liquid hourly space velocity is 0.1-10h ^-1 Preferably 0.2 to 5h ^-1 Hydrogen-oil volume ratio of 100-5000, preferably 200 to 1000.

The hydrocracking reaction apparatus may be any reaction apparatus sufficient to allow the hydrocarbon feedstock to react with the catalyst under hydrogenation reaction conditions, and may be, for example, a fixed bed reactor, a moving bed reactor, an ebullating bed reactor or a slurry bed reactor.

The present disclosure is further illustrated by the following examples, but is not limited thereto.

The pore volume and the specific surface area of the molecular sieve are measured by a static low-temperature adsorption capacity method (by adopting a national standard GB/T5816-1995 method) by adopting an ASAP 2400 model automatic adsorption instrument of American micromeritics instruments, and the specific method comprises the following steps: vacuumizing and degassing at 250 deg.C and 1.33Pa for 4 hr, contacting with nitrogen as adsorbate at-196 deg.C, and statically reaching adsorption balance; and calculating the nitrogen adsorption amount of the adsorbent according to the difference between the nitrogen gas inflow and the nitrogen gas remaining in the gas phase after adsorption, calculating the pore size distribution by using a BJH (British Ribose) formula, and calculating the specific surface area and the pore volume by using a BET (BET) formula.

The unit cell constant is determined by an X-ray diffractometer model D5005 of Siemens Germany, and is in accordance with the method of industry standard SH/T0339-92. The experimental conditions are as follows: cu target, ka radiation, solid detector, tube voltage 40kV, tube current 40mA, step scanning, step width of 0.02 degrees, prefabrication time of 2s and scanning range of 5-70 degrees.

The phosphorus content and the sodium content of the molecular sieve are measured by a 3271E type X-ray fluorescence spectrometer of Japan science and electric machinery industry Co., ltd, and the measuring method comprises the following steps: tabletting and forming a powder sample, carrying out rhodium target, detecting the spectral line intensity of each element by a scintillation counter and a proportional counter under the laser voltage of 50kV and the laser current of 50mA, and carrying out quantitative and semi-quantitative analysis on the element content by an external standard method.

The ratio of the B acid amount to the L acid amount of the molecular sieve is measured by a Bio-Rad IFS-3000 type infrared spectrometer. The specific method comprises the following steps: the molecular sieve sample is ground into fine powder and pressed into 10mg/cm ² The self-supporting sheet is placed in an in-situ cell of an infrared spectrometer at 350 ℃ and 10 DEG C ^-3 Surface purifying treatment for 2 hours under Pa vacuum degree, introducing pyridine saturated vapor after cooling to room temperature, adsorbing and balancing for 15 minutesThen, vacuum desorption is carried out for 30 minutes at 350 ℃, and the vibration spectrum of the adsorbed pyridine is measured after the temperature is reduced to room temperature. The scanning range is 1400cm ^-1 -1700cm ^-1 At 1540 + -5 cm ^-1 The ratio of the infrared absorption of the band to the weight and area of the sample piece defines the amount of B acid [ infrared absorption per unit area, per unit mass of the sample, expressed as: AB (cm) ² ·g) ^-1 ]. At 1450 + -5 cm ^-1 The ratio of the infrared absorption value of the band to the weight and area of the sample piece defines the L acid amount [ infrared absorption value per unit area, unit mass of the sample, expressed as: AL (cm) ² ·g) ^-1 ]The value AB/AL is defined as the ratio of the amount of the B acid to the amount of the L acid of the zeolite molecular sieve.

The molecular sieve is subjected to sample analysis by adopting a Varian UNITYING OVA300M nuclear magnetic resonance instrument, wherein the resonance frequency of Al MAS NMR is 78.162MHzs, the rotor speed is 3000Hz, the repetition delay time is 0.5s, the sampling time is 0.020s, the pulse width is 1.6 mus, the spectrum width is 54.7kHz, the data is collected at 2000 points, the cumulative frequency is 800 times, and the test temperature is room temperature.

Yield (%) of molecular sieve/dry weight of hydrothermally treated molecular sieve raw material × 100% of prepared molecular sieve.

Preparative examples 1-3 are provided to illustrate methods of preparing phosphorus-containing molecular sieves provided by the present disclosure.

Preparation of example 1

Taking NaY molecular sieve (product of China petrochemical catalyst Chang Ling Branch, product name NaY, unit cell constant of 2.468nm, specific surface area of 680 m) ² Per g, pore volume of 0.30ml/g, na ₂ O content 13.0 wt.%, al ₂ O ₃ 22 wt.%) was added 2.0mol/L of (NH) ₄ ) ₂ HPO ₄ Pulping the aqueous solution with the total amount of 1000ml of water, filtering, repeating the above process for three times to obtain a filter cake, drying at 100 deg.C for 1h to obtain phosphorus-containing molecular sieve raw material with unit cell constant of 2.468nm and specific surface area of 590m ² Per g, pore volume of 0.37ml/g, P ₂ O ₅ The content was 4.8% by weight, na ₂ The O content was 3.5% by weight.

100g of the phosphorus-containing molecular sieve raw material is put into a hydrothermal treatment device, 100% of water vapor is introduced, the temperature is raised to 450 ℃, the pressure in the device is controlled to be 0.8MPa, the hydrothermal treatment is constantly carried out for 8 hours, and then the molecular sieve material after the hydrothermal treatment is taken out.

According to the weight ratio of hydrochloric acid, ammonium chloride and phosphorus-containing molecular sieve raw materials (dry basis) of 0.2:0.4:1 preparing 100ml of hydrochloric acid-ammonium chloride aqueous solution, wherein the concentration of hydrochloric acid in the aqueous solution is 0.05mol/L, and the concentration of ammonium chloride in the aqueous solution is 0.07mol/L.

Taking 50g (dry basis) of the molecular sieve material subjected to the hydrothermal treatment, adding 500ml of deionized water, stirring and pulping to obtain molecular sieve slurry, and heating the molecular sieve slurry to 80 ℃. Based on 1L of molecular sieve slurry and H ⁺ And adding the prepared hydrochloric acid-ammonium chloride aqueous solution into the molecular sieve slurry at a constant speed for three times at a speed of 2mol/h, reacting for 4 hours at a constant temperature after each time of adding acid, filtering, and taking a filter cake to continue to add acid for the next time in the same manner. After the last time of acid addition and reaction for 4 hours, collecting the solid product, and drying at 180 ℃ for 3 hours to obtain the phosphorus-containing molecular sieve Y-1, wherein the phosphorus-containing molecular sieve Y-1 is obtained ²⁷ The Al-NMR structural spectrum is shown in FIG. 1, and the properties are shown in Table 1.

Preparation of example 2

Taking PSRY molecular sieve (product name PSRY of China petrochemical catalyst ChangLing Brand, manufactured by Inc.), wherein the unit cell constant is 2.456nm, and the specific surface area is 620m ² Per g, pore volume of 0.39ml/g, na ₂ O content 2.2 wt.%, P ₂ O ₅ Content of 1.5 wt.%, al ₂ O ₃ Content of 18 wt%) of the phosphorus-containing molecular sieve raw material, adding deionized water, pulping, filtering, and drying at 70 ℃ for 2 hours to obtain the phosphorus-containing molecular sieve raw material with the water content of 35 wt%.

Crushing the phosphorus-containing molecular sieve raw material, sieving to 5-20 meshes (wherein 1-500 mm particles account for 70 wt% of the total weight of the phosphorus-containing molecular sieve raw material), placing into a hydrothermal treatment device, introducing 100% of water vapor, heating to 580 ℃, controlling the pressure in the device to be 0.4MPa, performing hydrothermal treatment for 2 hours constantly, and taking out the molecular sieve material after the hydrothermal treatment.

According to the weight ratio of sulfuric acid to phosphorus-containing molecular sieve raw material (dry basis) of 0.02:1 preparing 250ml of sulfuric acid aqueous solution, wherein the concentration of sulfuric acid in the aqueous solution is 0.2mol/L.

Taking 50g (dry basis) of the molecular sieve material subjected to the hydrothermal treatment, adding 500ml of deionized water, stirring and pulping to obtain molecular sieve slurry, and heating to 80 ℃. Based on 1L of molecular sieve slurry and H ⁺ And (3) uniformly adding the prepared sulfuric acid aqueous solution into the molecular sieve slurry for three times at a constant speed according to the speed of 0.5mol/h, reacting for 2 hours at a constant temperature after each time of acid addition, filtering, and taking a filter cake to continue to add acid for the next time according to the same mode. After the last time of acid addition and reaction for 2 hours, collecting the solid product, and drying at 100 ℃ for 8 hours to obtain the phosphorus-containing molecular sieve Y-2, wherein the phosphorus-containing molecular sieve Y-2 is obtained ²⁷ The structural spectrum of Al-NMR is shown in figure 1, and the properties are shown in table 1.

Preparation of example 3

A phosphorus-containing molecular sieve was prepared according to the method of preparation example 2, except that the phosphorus-containing molecular sieve raw material was crushed, sieved to 5 to 20 mesh (wherein 5mm to 100mm particles account for 70 wt% of the total weight of the phosphorus-containing molecular sieve raw material), and then subjected to hydrothermal treatment and subsequent operations according to the method of preparation example 2 to obtain a phosphorus-containing molecular sieve Y-3, which was a phosphorus-containing molecular sieve ²⁷ The Al-NMR structural spectrum is shown in FIG. 1, and the properties are shown in Table 1.

Comparative examples 1-4 are prepared to illustrate different methods of preparing phosphorus-containing molecular sieves than are disclosed herein.

Preparation of comparative example 1

The phosphorus-containing molecular sieve of this comparative preparation example is a PSRY molecular sieve identical to that of preparation example 2, and its preparation method can refer to the preparation method of phosphorus-containing zeolite disclosed in CN1088407C, which comprises directly mixing a phosphorus-containing compound with a raw material zeolite in a weight ratio of 0.1 to 40, heating at 50 to 550 ℃ for at least 0.1 hour under a closed condition, washing the resulting product with deionized water until no acid radical ion is present, and recovering phosphorus-containing zeolite. It was named RY-1, which ²⁷ The Al-NMR structural spectrum is shown in FIG. 1, and the properties are shown in Table 1.

Preparation of comparative example 2

Taking an HY molecular sieve (product name HY, unit cell constant 2.465nm, produced by Zhongpetrochemical catalyst Chang Ling Branch Co., ltd.),the specific surface area is 580m ² Per g, pore volume of 0.33ml/g, na ₂ 0.3 wt.% of O, al ₂ O ₃ Content of 22 wt%) was put into a hydrothermal treatment apparatus, 100% steam was introduced, the temperature was raised to 450 ℃, the pressure in the apparatus was controlled to 0.8MPa, and the molecular sieve material after hydrothermal treatment was taken out after constant hydrothermal treatment for 8 hours.

According to the weight ratio of 0.08 of hydrochloric acid, ammonium chloride and phosphorus-containing molecular sieve raw materials: 1.5:1, 50ml of hydrochloric acid-ammonium chloride aqueous solution is prepared, and in the aqueous solution, the concentration of hydrochloric acid is 0.1mol/L, and the concentration of ammonium chloride is 0.16mol/L.

Taking 50g (dry basis) of the molecular sieve material subjected to the hydrothermal treatment, adding 500ml of deionized water, stirring and pulping to obtain molecular sieve slurry, and heating the molecular sieve slurry to 80 ℃. Based on 1L of molecular sieve slurry and H ⁺ And (3) uniformly adding the prepared hydrochloric acid-ammonium chloride aqueous solution into the molecular sieve slurry at a constant speed of 2mol/h for three times, reacting at a constant temperature for 4h after each time of acid addition, filtering, and taking a filter cake to continue to add acid for the next time in the same way. After the last time of acid addition and reaction for 4 hours, collecting the solid product, and drying at 180 ℃ for 3 hours to obtain the phosphorus-containing molecular sieve RY-2 ²⁷ The Al-NMR structural spectrum is shown in FIG. 1, and the properties are shown in Table 1.

Preparation of comparative example 3

300g of PSRY molecular sieve (same as preparation example 2) is taken, and NH with the concentration of 0.5mol/L is added ₄ 600ml of Cl aqueous solution is pulped by deionized water, the total amount of water is 1000ml, the temperature is heated to 90 ℃, and ammonium exchange is carried out for 3h. Then filtered, washed twice with deionized water and the filter cake heated at 600 ℃ for 4h at atmospheric pressure.

According to the weight ratio of 0.5:0.36:1 preparing 300ml of hydrochloric acid-ammonium chloride aqueous solution, wherein the concentration of hydrochloric acid in the aqueous solution is 0.6mol/L, and the concentration of ammonium chloride in the aqueous solution is 0.3mol/L.

Taking 50g (dry basis) of the molecular sieve material subjected to the hydrothermal treatment, adding 500ml of deionized water, stirring and pulping to obtain molecular sieve slurry, and heating the molecular sieve slurry to 80 ℃. Based on 1L of molecular sieve slurry and H ⁺ In terms of 2mol/hAdding the prepared hydrochloric acid-ammonium chloride aqueous solution into the molecular sieve slurry at constant speed for three times, reacting at constant temperature for 4 hours after each time of adding acid, filtering, and taking a filter cake to continue adding acid next time according to the same mode. After the last time of acid addition and reaction for 4 hours, collecting the solid product, and drying at 180 ℃ for 3 hours to obtain the phosphorus-containing molecular sieve RY-3, wherein the phosphorus-containing molecular sieve RY-3 is prepared ²⁷ The Al-NMR structural spectrum is shown in FIG. 1, and the properties are shown in Table 1.

Preparation of comparative example 4

Taking 300g of PSRY molecular sieve (same as preparation example 2), adding deionized water for pulping, wherein the total amount of water is 1000ml, filtering, and drying at 70 ℃ for 2h to obtain the phosphorus-containing molecular sieve raw material with the water content of 65%.

And (3) putting the obtained phosphorus-containing molecular sieve raw material into a hydrothermal treatment device, heating to 580 ℃, controlling the pressure in the device to be 0.4MPa, performing hydrothermal treatment for 2 hours constantly, and taking out the molecular sieve material after the hydrothermal treatment.

According to the weight ratio of 0.8:1 preparing 500ml of sulfuric acid aqueous solution, wherein the concentration of sulfuric acid in the aqueous solution is 0.2mol/L.

Taking 50g (dry basis) of the molecular sieve material subjected to the hydrothermal treatment, adding 500ml of deionized water, stirring and pulping to obtain molecular sieve slurry, and heating to 80 ℃. Adding the prepared sulfuric acid aqueous solution into the molecular sieve slurry for three times, wherein the acid adding mode for each time is directly pouring, then reacting for 2 hours at constant temperature, filtering, and taking the filter cake to continue to add acid for the next time according to the same mode. After the last time of acid addition and reaction for 2 hours, collecting a solid product, and drying at 100 ℃ for 8 hours to obtain a phosphorus-containing molecular sieve RY-4 ²⁷ The Al-NMR structural spectrum is shown in FIG. 1, and the properties are shown in Table 1.

TABLE 1

As can be seen from table 1, the phosphorus-containing molecular sieve provided by the present disclosure has a higher ratio of the amount of the B acid to the amount of the L acid, and can improve the yield of the molecular sieve under the condition of controlling the particle size range of the phosphorus-containing molecular sieve raw material.

Examples 1-7 are provided to illustrate hydrocracking catalysts and methods of making the same provided by the present disclosure. Comparative examples 1-4 are presented to illustrate catalysts prepared using different molecular sieves than those of the present disclosure.

Example 1

67.6g of pseudo-boehmite powder PB90 (produced by Zhongpetrochemical catalyst ChangLing division, pore volume 0.9mL/g, water content 28 wt.%), 15.8g of Beta molecular sieve (produced by Zhongpetrochemical catalyst ChangLing division, silica-alumina ratio 87, pore volume 0.43mL/g, dry content 0.76, the same below), 158g of weakly acidic silica-alumina (produced by Germany Condea corporation, trade name Sira-40, pore volume 0.88mL/g, specific surface 468m2/g, silica weight content 40%, acidity value of infrared B0.04 mmol/g, water content 24 wt.%) were mixed uniformly with 24.7g of Y-1 molecular sieve (water content 19 wt.%), sesbania powder 8.3 g, 195mL of aqueous solution containing 7.2mL of nitric acid (nitric acid content 65-68 wt.%) was extruded into trilobe strips with a diameter of 1.6 mm, dried at 120 ℃ for 3 hours, and calcined at 600 ℃ to obtain a carrier.

After cooling to room temperature, 100g of CS-1 carrier was immersed in 80ml of an aqueous solution containing 52 g of ammonium metatungstate (82 wt% tungsten oxide, available from mitsubao cemented carbide works, japan), 8.7 g of basic nickel carbonate (51 wt% nickel oxide, available from jiangsu slow chemical limited), and 10.5g of citric acid, and dried at 120 ℃ for 10 hours to obtain the hydrocracking catalyst prepared in this example, the composition of which is shown in table 2.

Examples 2 to 3

A catalyst was prepared as in example 1 except that the molecular sieves used were Y-2 and Y-3, respectively, and the catalyst composition is shown in Table 2.

Example 4

194g of pseudo boehmite powder SB (product name SB powder, dry basis content 0.72, produced by Sasol company) and 39.5g of Beta molecular sieve are uniformly mixed, then 12.3g of Y-2 molecular sieve (water content is 19 wt%), 26.3g of Sira-40 and 2.2 g of sesbania powder are uniformly mixed, 200ml of aqueous solution containing 2ml of nitric acid (content of 65-68 wt% in Beijing chemical reagent factory) is added, a trilobal strip with the diameter of 1.6 mm of an external circle is extruded, the drying is carried out at 120 ℃, and the roasting is carried out at 550 ℃ for 3 hours, thus obtaining the carrier CS-4.

After cooling to room temperature, 100g of the CS-4 support was immersed in 90ml of an aqueous solution containing 24.1 g of ammonium heptamolybdate (tianjin tetragonal chemical company, ltd., molybdenum oxide content 82 wt%), dried at 120 ℃ for 10 hours, then immersed in 50ml of an aqueous solution containing 46.2 g of nickel nitrate (njaku yixing brady chemical company, ltd., nickel oxide content 25.6 wt%), baked at 90 ℃ for 5 hours, and baked at 420 ℃ for 3 hours, to obtain the hydrocracking catalyst prepared in this example, the composition of which is shown in table 2.

Example 5

28.2g of pseudo-boehmite powder PB100 (produced by Zhongpetrochemical catalyst ChangLing division, the pore volume is 1.05ml/g, the water content is 29 weight percent) and 148g of Y-3 molecular sieve (the water content is 19 weight percent), 26.7g of beta molecular sieve, 52.6g of Sira-40 and 7.8 g of sesbania powder are uniformly mixed, 144ml of aqueous solution containing 25g of urea (Beijing chemical reagent factory) is added to extrude into trilobal strips with the circumscribed circle diameter of 1.6 mm, the three-lobed strips are dried at 120 ℃ and roasted at 600 ℃ for 3 hours, and the carrier CS-5 is obtained.

After cooling to room temperature, 100g of the carrier was immersed in 85ml of an aqueous solution containing 39.2 g of ammonium metatungstate (91 wt% tungsten oxide, available from Sichuan tribute cemented carbide Co., ltd.), 20.56 g of nickel nitrate (25.6 wt% nickel oxide, available from Jiangsu Yixing brady chemical Co., ltd.), and 0.26g of ethylene glycol, and dried at 180 ℃ for 3 hours to obtain the hydrocracking catalyst prepared in this example, the composition of which is shown in Table 2.

Example 6

A catalyst was prepared by following the procedure of example 4 except that 100g of the CS-4 carrier was impregnated with 95ml of an aqueous solution containing 17.6g of ammonium heptamolybdate (Tianjin tetragonal chemical Co., ltd., molybdenum oxide content of 82% by weight), dried at 120 ℃ for 10 hours, and then impregnated with 55ml of an aqueous solution containing 20.6g of nickel nitrate (Jiangsu Yixing Slow chemical Co., ltd., nickel oxide content of 25.6% by weight), baked at 90 ℃ for 5 hours, and baked at 420 ℃ for 3 hours, to obtain a hydrocracking catalyst prepared in this example, the composition of which is shown in Table 2.

Example 7

A catalyst was prepared by following the procedure of example 4 except that the CS-4 carrier was pulverized into 80-200 mesh powder, 74.5g of ammonium heptamolybdate (same as example 4) and 4g,6g of sesbania powder (same as example 4) were added and mixed uniformly, 150ml of an aqueous solution containing 25g of urea (Beijing chemical Co., ltd.) was added, extruded into a cylindrical bar having a circumscribed circle diameter of 3.0 mm, dried at 90 ℃ for 5 hours and calcined at 450 ℃ for 3 hours to obtain a hydrocracking catalyst prepared in this example, the composition of which is shown in Table 2.

Comparative examples 1 to 4

A catalyst was prepared by following the procedure of example 1 except that RY-1, RY-2, RY-3 and RY-4, respectively, were used as the molecular sieves.

TABLE 2

Test examples

This test example was used to test the catalytic activity of the catalysts of examples 1-7 and comparative examples 1-4 for hydrocracking reactions. Wherein, the used raw oil is the Suzuki decompression gas oil, and the physicochemical properties are shown in Table 3.

TABLE 3

Item	Raw oil
		Density (20 ℃ C.) (g/cm) ³ )	0.8885
S (wt%)	16000
		N(mg/L)	352
Simulated distillation (ASTM D-2887) (. Degree.C.)
		Initial boiling point	291
50% by weight	391
		90% by weight	421

In the present test example, the evaluation method of the catalyst was: the catalyst was crushed into particles of 2 to 3 mm in diameter, 20 ml of the catalyst was charged into a30 ml fixed bed reactor, and before the reaction, the catalyst was first sulfurized with kerosene containing 2% by weight of carbon disulfide in a hydrogen atmosphere according to the following procedure, and then the reaction materials were switched to carry out the reaction.

And (3) vulcanization procedure: heating to 150 ℃, introducing vulcanized oil, keeping the temperature for 1h, allowing the adsorbed temperature wave to pass through two reactors, heating to 230 ℃ at the speed of 60 ℃/h, stabilizing for 2h, heating to 360 ℃ at the speed of 60 ℃/h, and stabilizing for 6h. Replacing the raw oil, adjusting the reaction conditions below the reaction temperature, and stabilizing for at least 20h.

Reaction conditions are as follows: the reaction temperature is 365 ℃, the hydrogen partial pressure is 6.4MPa, and the Liquid Hourly Space Velocity (LHSV) is 1h ^-1 The hydrocracking reaction was carried out under the condition that the hydrogen-oil ratio (volume) was 800.

The conversion was calculated according to the following formula:

conversion (%) = (amount of fraction greater than 350 ℃ in the feed-amount of fraction greater than 350 ℃ in the product oil)/amount of fraction greater than 350 ℃ in the feed x 100%.

The calculated conversions of examples 1-7 and comparative examples 2-4 were divided by the conversion of comparative example 1 to obtain the relative activity of each catalyst, and the results are shown in table 4.

TABLE 4

Catalyst and process for producing the same	Relative Activity (%)	Fraction condensation point (DEG C) of more than 350 DEG C
			Example 1	143.1	4
Example 2	158.1	2
			Example 3	153.7	2
Example 4	171.2	0
			Example 5	175.2	-4
Example 6	148	-1
			Example 7	141	-2
Comparative example 1	100.0	9
			Comparative example 2	112.0	7
Comparative example 3	87.1	14
			Comparative example 4	138	6

As can be seen from table 4, under the same reaction conditions, the catalysts provided by the present disclosure containing the phosphorus-containing molecular sieves of preparation examples 1-3 have increased relative catalytic activity by more than about 20% and lower congealing point, indicating better cold flow performance, relative to the catalysts of comparative examples 1-4 prepared by conventional methods.

The preferred embodiments of the present disclosure are described in detail with reference to the accompanying drawings, however, the present disclosure is not limited to the specific details of the above embodiments, and various simple modifications may be made to the technical solution of the present disclosure within the technical idea of the present disclosure, and these simple modifications all belong to the protection scope of the present disclosure.

It should be noted that, in the foregoing embodiments, various features described in the above embodiments may be combined in any suitable manner, and in order to avoid unnecessary repetition, various combinations that are possible in the present disclosure are not described again.

In addition, any combination of various embodiments of the present disclosure may be made, and the same should be considered as the disclosure of the present disclosure, as long as it does not depart from the spirit of the present disclosure.

Claims

1. A hydrocracking catalyst, which is characterized by comprising 45 to 85 wt% of a carrier, 5 to 40 wt% of a first metal component and 1 to 15 wt% of a second metal component, wherein the carrier is calculated by the weight of the carrier and the metal oxide is calculated by the weight of the carrier;

the carrier comprises a phosphorus-containing Y-type molecular sieve, a Beta molecular sieve, weakly acidic silicon aluminum and a heat-resistant inorganic oxide, wherein the weight ratio of the phosphorus-containing Y-type molecular sieve to the Beta molecular sieve to the weakly acidic silicon aluminum to the heat-resistant inorganic oxide is (0.03-7): (0.03 to 7): (0.1 to 2.5): 1; the first metal component is a metal selected from group VIB; the second metal component is a metal selected from group VIII;

the phosphorus content of the phosphorus-containing Y-shaped molecular sieve is 0.3 to 5 weight percent, the pore volume is 0.2 to 0.95mL/g, and the ratio of pyridine infrared B acid to L acid is 2 to 10; the phosphorus-containing Y-type molecular sieve ²⁷ In Al-NMR structural spectrum, I _60ppm /I _-1ppm Is 5 to 40,I _-1ppm /I _±6ppm 0.4 to 2;

wherein, I _60ppm /I _-1ppm Represents the peak height ratio of framework aluminum to non-framework aluminum at 60 + -1 ppm and-1 + -1 ppm; i is _-1ppm /I _±6ppm Represents the ratio of two distinct characteristic peaks at 0ppm of non-framework aluminum at-1 + -1 ppm and-5.5 + -2 ppm or 3-7 ppm, I _±6ppm The larger peak height of-5.5 +/-2 ppm and 3-7 ppm is taken.

2. The catalyst of claim 1, wherein the catalyst comprises 60 to 80 wt% of the carrier, 10 to 35 wt% of the first metal component, and 2 to 10 wt% of the second metal component, based on the metal oxide, based on the dry weight of the catalyst;

the weight ratio of the phosphorus-containing Y-type molecular sieve to the Beta molecular sieve to the weakly acidic silicon-aluminum to the heat-resistant inorganic oxide is (0.5-6): (0.3 to 4): (0.8 to 2): 1.

3. the catalyst of claim 1 or 2, wherein the phosphorus-containing Y-type molecular sieve is prepared by a process comprising the steps of:

a. carrying out hydro-thermal treatment on a phosphorus-containing molecular sieve raw material for 0.5-10h at the temperature of 350-700 ℃ and the pressure of 0.1-2MPa in the presence of water vapor to obtain a hydro-thermally treated molecular sieve material; calculated by oxide and based on the dry weight of the phosphorus-containing molecular sieve raw material, the phosphorus content of the phosphorus-containing molecular sieve raw material is 0.1 to 15 weight percent, and the sodium content is 0.5 to 4.5 weight percent;

b. b, adding water into the molecular sieve material subjected to the hydrothermal treatment obtained in the step a for pulping to obtain molecular sieve slurry, heating the molecular sieve slurry to 40-95 ℃, keeping the temperature, and continuously adding an acid solution into the molecular sieve slurry, wherein the ratio of the weight of acid in the acid solution to the dry weight of the phosphorus-containing molecular sieve raw material is (0.01-0.6): 1, based on 1L of the molecular sieve slurry, taking H as reference ⁺ And (3) the adding speed of the acid solution is 0.05-10 mol/h, the constant temperature reaction is carried out for 0.5-20h after the acid is added, and a solid product is collected.

4. The catalyst of claim 3, wherein in the step a, the phosphorus-containing molecular sieve raw material is a phosphorus-containing Y-type molecular sieve, the unit cell constant of the phosphorus-containing Y-type molecular sieve is 2.425 to 2.47nm, and the specific surface area is 250 to 750m m ² The pore volume is 0.2 to 0.95mL/g.

5. The catalyst of claim 4, wherein in the step a, the water content of the phosphorus-containing molecular sieve raw material is 10-40 wt%;

the raw material of the phosphorus-containing molecular sieve is granular, the content of the raw material of the phosphorus-containing molecular sieve with the granularity ranging from 1mm to 500mm is 10 to 100 percent by weight of the total weight of the raw material of the phosphorus-containing molecular sieve, and the granularity is calculated by the diameter of an excircle of the granule.

6. The catalyst of claim 5, wherein the content of the phosphorus-containing molecular sieve raw material with the particle size ranging from 1mm to 500mm is 30 to 100 percent by weight of the total weight of the phosphorus-containing molecular sieve raw material.

7. The catalyst of claim 6, wherein the content of the phosphorus-containing molecular sieve raw material with the particle size ranging from 5mm to 100mm is 30 to 100 wt% of the total weight of the phosphorus-containing molecular sieve raw material.

8. The catalyst of claim 3, wherein in step b, the ratio of the weight of water in the molecular sieve slurry obtained after beating to the dry weight of the phosphorus-containing molecular sieve feedstock is (14-5): 1.

9. the catalyst of claim 3, wherein the preparation of the phosphorus-containing Y-type molecular sieve further comprises: in the step b, adding ammonium salt into the molecular sieve slurry in the process of adding an acid solution, wherein the ammonium salt is ammonium nitrate, ammonium chloride or ammonium sulfate, or the combination of two or three of the ammonium nitrate, the ammonium chloride or the ammonium sulfate; the weight of the ammonium salt and the dry basis weight of the phosphorus-containing molecular sieve raw material are in a ratio of (0.1-2.0): 1.

10. the catalyst of claim 3, wherein in the step b, the acid concentration of the acid solution is 0.01 to 15.0mol/L, and the acid is phosphoric acid, sulfuric acid, nitric acid, hydrochloric acid, citric acid, tartaric acid, formic acid or acetic acid, or a combination of two or three of the phosphoric acid, the sulfuric acid, the nitric acid, the hydrochloric acid, the citric acid, the tartaric acid, the formic acid or the acetic acid.

11. The catalyst of claim 3, wherein the preparation of the phosphorus-containing Y-type molecular sieve further comprises: collecting the solid product, then washing with water and drying to obtain a phosphorus-containing molecular sieve; the drying conditions are as follows: the temperature is 50 to 350 ℃; the time is 1 to 24h.

12. The catalyst of claim 11, wherein the drying conditions are: the temperature is 70 to 200 ℃; the time is 2 to 6h.

13. The catalyst of claim 1, wherein,the framework silica-alumina ratio of the Beta molecular sieve is 20 to 120, and the specific surface area is 200 to 650m ² (iii) the pore volume is 0.20 to 0.75mL/g;

the infrared B acidity value of the weakly acidic silicon-aluminum is 0.01 to 0.1mmol/g, the silicon content is 20 to 60 wt% in terms of silicon dioxide, and the pore volume is 0.45 to 0.95mL/g; the weakly acidic silicon-aluminum is silicon-containing aluminum oxide and/or amorphous silicon-aluminum.

14. The catalyst of claim 1 wherein the refractory inorganic oxide is alumina, zirconia, magnesia, thoria, beryllia, boria or cadmium oxide, or a mixture of two or three thereof; the first metal component is molybdenum and/or tungsten; the second metal component is at least one of iron, nickel or cobalt, or a mixture of two or three of them.

15. A process for preparing a hydrocracking catalyst according to any one of claims 1 to 14, characterized in that the process comprises: the impregnation liquid containing the metal precursor is contacted with the carrier for impregnation, and then the material obtained after the impregnation is dried.

16. The method of claim 15, wherein the method further comprises: mixing a phosphorus-containing Y-type molecular sieve, a Beta molecular sieve, weakly acidic silicon aluminum, a heat-resistant inorganic oxide, a peptizing agent and a lubricant, and then molding, drying and roasting to obtain the carrier.

17. The method of claim 15, wherein the metal precursor comprises a first metal precursor and a second metal precursor, wherein the first metal precursor is an inorganic acid, an inorganic salt, or an organic compound of a first metal, or a combination of two or three thereof; the inorganic salt is nitrate, carbonate, basic carbonate, hypophosphite, phosphate, sulfate or chloride; the organic substituent in the first metal organic compound is hydroxyl, carboxyl, amino, ketone, ether or alkyl, or the combination of two or three of the hydroxyl, carboxyl, amino, ketone, ether or alkyl;

the second metal precursor is selected from inorganic acid of a second metal, inorganic salt of the second metal or a second metal organic compound, or a combination of two or three of the inorganic acid, the inorganic salt and the second metal; the inorganic salt is nitrate, carbonate, basic carbonate, hypophosphite, phosphate, sulfate or chloride; the organic substituent in the second metal organic compound is hydroxyl, carboxyl, amine, ketone, ether or alkyl, or the combination of two or three of the above.

18. The method of claim 15, wherein the impregnating solution further comprises an organic additive; the concentration of the organic additive is 2-300g/L; the organic additive is ethylene glycol, glycerol, polyethylene glycol, diethylene glycol, butanediol, acetic acid, maleic acid, oxalic acid, nitrilotriacetic acid, 1, 2-cyclohexanediamine tetraacetic acid, citric acid, tartaric acid, malic acid, ethylenediamine, diethylenetriamine, cyclohexanediamine tetraacetic acid, glycine, nitrilotriacetic acid, ethylenediaminetetraacetic acid or ammonium ethylenediaminetetraacetate, or a combination of two or three of them.

19. The method of claim 15, wherein the drying conditions are: the temperature is 80-350 ℃, and the time is 0.5-24 hours.

20. The method of claim 15, further comprising the step of drying the contacted material and then calcining the dried material under the following conditions: the temperature is 350-600 ℃, and the time is 0.2-12 hours.

21. Use of a hydrocracking catalyst as claimed in any one of claims 1 to 14 in the hydrocracking reaction of a hydrocarbon feedstock.

22. The use according to claim 21, wherein the hydrocarbon feedstock is selected from straight run gas oil, vacuum gas oil, demetallized oil, atmospheric residue, deasphalted vacuum residue, coker distillate, catalytically cracked distillate, shale oil, tar sand oil or coal liquefaction oil;

the conditions of the hydrocracking reaction are as follows: the reaction temperature is 200-650 ℃; the reaction pressure is 3-24 MPa; the liquid hourly space velocity is 0.1-10 hours ^-1 (ii) a The volume ratio of hydrogen to oil is 100-5000.

23. The use according to claim 22, wherein the hydrocracking reaction conditions are: the reaction temperature is 300-510 ℃; the reaction pressure is 4-15 MPa; liquid hourly space velocity of 0.2-5 hours ^-1 (ii) a The volume ratio of hydrogen to oil is 200-1000.