CN107970990B

CN107970990B - Catalytic cracking auxiliary agent for increasing propylene yield and preparation method thereof

Info

Publication number: CN107970990B
Application number: CN201610920938.4A
Authority: CN
Inventors: 刘倩倩; 朱玉霞; 任飞; 田辉平; 罗一斌; 欧阳颖
Original assignee: Sinopec Research Institute of Petroleum Processing; China Petrochemical Corp
Current assignee: Sinopec Research Institute of Petroleum Processing; China Petrochemical Corp
Priority date: 2016-10-21
Filing date: 2016-10-21
Publication date: 2019-12-27
Anticipated expiration: 2036-10-21
Also published as: CN107970990A

Abstract

The present disclosure relates to a catalytic cracking assistant for increasing the yield of propylene and a preparation method thereof, wherein the assistant comprises 10-75 wt% of phosphorus-containing and metal-loaded MFI structure molecular sieve based on the dry weight of the assistant, 3-40 wt% of phosphorus-aluminum inorganic binder based on the dry weight, 1-30 wt% of other inorganic binders based on oxides, and 0-60 wt% of second clay based on the dry weight. When the auxiliary agent provided by the disclosure is used in a catalytic cracking process, the propylene yield and the propylene selectivity can be effectively improved.

Description

Catalytic cracking auxiliary agent for increasing propylene yield and preparation method thereof

Technical Field

The invention relates to a catalytic cracking auxiliary agent for increasing the yield of propylene and a preparation method thereof.

Background

The low-carbon olefin is an important organic chemical raw material, and with the rapid increase of the demand of derivatives thereof, the worldwide demand for the low-carbon olefin is increased year by year. The fluid catalytic cracking is one of the important production processes for producing low-carbon olefins, and in order to increase the yield of the low-carbon olefins, the adoption of a catalyst or an auxiliary agent containing zeolite with an MFI structure is an effective technical approach.

The ZSM-5 molecular sieve is a three-dimensional mesoporous high-silicon molecular sieve which is successfully prepared by Mobil corporation firstly, and has excellent performances on shape selective cracking, isomerization and aromatization due to the unique pore channel structure. The ZSM-5 molecular sieve has the pore passages allowing straight-chain alkane to enter, limiting the entering of multi-side chain hydrocarbon and cyclic hydrocarbon, and can preferentially crack low-octane alkane and olefin in gasoline into C3 and C4 olefin. The ZSM-5 molecular sieve is applied to catalytic cracking and catalytic cracking catalysts, can effectively increase the yield of liquefied gas and improve the concentration of propylene in the liquefied gas.

Although the conventional ZSM-5 molecular sieve can improve the yield of propylene by higher silica-alumina ratio and the shape selection effect of a pore channel, larger reactant molecules are difficult to enter a crystal pore channel for reaction due to the narrow pore channel structure, the effective reaction area of the molecular sieve is reduced, and the reaction activity of the molecular sieve is reduced; on the other hand, the molecules of the larger products such as isoparaffin and aromatic hydrocarbon are not easy to diffuse out from the inside of the molecular sieve pore channel, so that secondary reactions such as excessive hydrogen transfer, coking and the like are caused to cause molecular sieve inactivation and reaction selectivity reduction. In the new catalytic cracking process using heavy oil as raw material, the above problem is inevitably made more prominent by the narrow pore opening of the ZSM-5 molecular sieve pore channel.

There are several types of solutions to this problem. One is to synthesize small crystal size such as ZSM-5 molecular sieve with nanometer level to shorten diffusion path. However, the small-grain molecular sieve has inherent weaknesses such as difficult filtration and poor hydrothermal structural stability. And the second is directly synthesizing the ZSM-5 molecular sieve material containing hierarchical pores. However, such methods require the addition of a template agent, and are complicated in process and high in cost. Another method is a molecular sieve post-modification method, which mainly adopts a desilication method or a desilication and dealumination coupling method.

Chinese patent CN103848438A discloses a method for preparing a modified ZSM-5 molecular sieve with a high mesoporous area, which comprises the steps of firstly exchanging and washing a roasted molecular sieve with acidic solutions such as nitric acid and hydrochloric acid for multiple times, drying, then roasting for the second time, desiliconizing the molecular sieve with inorganic base after roasting, washing the molecular sieve with dilute acid for multiple times after desiliconization and filtration, drying, roasting for the third time, exchanging ammonium salt ions for multiple times after roasting, and roasting for the fourth time after drying to obtain the molecular sieve with the high mesoporous area.

Chinese patent CN 1465527A discloses MFI structure zeolite containing phosphorus and transition metal, and the anhydrous chemical expression of the zeolite is (0-0.3) Na calculated by the mass of oxide₂O(0.5-5)Al₂O₃(1.3-10)P₂O₅(0.7-15)M₂O₃(70-97)SiO₂Wherein M is selected from one of transition metals Fe, Co and Ni. When the zeolite is applied to the catalytic cracking process of petroleum hydrocarbon, the yield and selectivity of C2-C4 olefin can be improved, and the liquefied gas yield is higher.

Chinese patent CN 1611299a discloses an MFI structure molecular sieve containing phosphorus and metal components, which has an anhydrous chemical expression, in terms of the weight of oxides: (0-0.3) Na₂O(0.5-5.5)Al₂O₃(1.3-10)P₂O₅(0.7-15)M1_xO_y(0.01-5)M2_mO_n(70-97)SiO₂Wherein M1 is selected from one of transition metals Fe, Co and Ni, and M2 is selected from any one of metals Zn, Mn, Ga and Sn.

Chinese patent CN1676579 discloses a hydrocarbon conversion catalyst, based on the total amount of the catalyst, the content of zeolite is 1-60 wt%, calculated by oxide, the content of adjuvant is 0.1-10 wt%, the content of heat-resistant inorganic oxide is 5-99 wt%, the content of clay is 0-70 wt%, the zeolite is a zeolite with MFI structure containing transition metal and phosphorus or a mixture of the zeolite and a large pore zeolite, calculated by the total amount of zeolite, the content of the zeolite with MFI structure is 75-100 wt%, the content of the large pore zeolite is 0-25 wt%; the transition metal and phosphorus containing zeolite with MFI structure has the following anhydrous chemical expression based on the mass of the oxides: (0-0.3) Na₂O·(0.3--5)Al₂O₃(1.0-10)P₂O₅(0.7-15)M_xO_y(0-10)RE₂O₃(70-98)SiO₂The auxiliary agent is selected from one or more of alkaline earth metal, VIB group metal, VIII group non-noble metal and rare earth metal in the periodic table of elements.

At present, for most catalytic cracking units, increasing the concentration of propylene in liquefied gas is an important way to increase the economic efficiency of the catalytic cracking unit under the premise of the same yield of liquefied gas. The zeolite material and the catalyst disclosed by the prior art are used as an auxiliary agent in the catalytic cracking process, the selectivity of propylene is not high, the concentration of propylene in liquefied gas is low, the conventional MFI structure molecular sieve modified by phosphorus and transition metal is used for producing propylene by catalytic cracking, and the yield of dry gas and coke is high.

Disclosure of Invention

The invention aims to provide a catalytic cracking auxiliary agent for increasing the yield of propylene and a preparation method thereof.

In order to achieve the above objects, the present disclosure provides a catalytic cracking assistant for increasing propylene yield, which comprises, based on the dry weight of the assistant, 10-75 wt% of phosphorus-containing and metal-loaded MFI structure molecular sieve, 3-40 wt% of phosphorus-aluminum inorganic binder, 1-30 wt% of other inorganic binders, and 0-60 wt% of second clay; wherein the phosphorus-aluminum inorganic binder is phosphorus-aluminum glue and/or phosphorus-aluminum inorganic binder containing first clay, and the phosphorus-aluminum inorganic binder containing first clay comprises Al based on the dry weight of the phosphorus-aluminum inorganic binder containing first clay₂O₃15-40% by weight, calculated as P, of an aluminium component₂O₅45-80 wt% of phosphorus component and more than 0 and not more than 40 wt% of first clay calculated on dry basis weight, and the P/Al weight ratio is 1.0-6.0, pH value is 1-3.5, solid content is 15-60 wt%; n (SiO) of the molecular sieve₂)/n(Al₂O₃) Greater than 18 and less than 70; with P₂O₅The phosphorus content of the molecular sieve is 1-15 wt% based on the dry weight of the molecular sieve; the content of the loaded metal in the molecular sieve is 0.1-5 wt% based on the oxide of the loaded metal and the dry basis weight of the molecular sieve; the Al distribution parameter D of the molecular sieve meets the following requirements: d is more than or equal to 0.6 and less than or equal to0.85, wherein D ═ al (s)/al (c), al(s) represents the aluminum content of any region greater than 100 square nanometers within a distance H inward from the edge of the crystal face of the molecular sieve crystal as measured by TEM-EDS, and al (c) represents the aluminum content of any region greater than 100 square nanometers within a distance H outward from the geometric center of the crystal face of the molecular sieve crystal as measured by TEM-EDS, wherein H is 10% of the distance from a certain point on the edge of the crystal face to the geometric center of the crystal face; the proportion of the mesopore volume of the molecular sieve in the total pore volume is 40-70% by volume, and the proportion of the mesopore volume with the pore diameter of 2-20 nm in the total mesopore volume is more than 85% by volume; the ratio of the strong acid amount of the molecular sieve to the total acid amount is 45-75%, and the ratio of the acid amount of the B acid to the acid amount of the L acid is 8-30.

Preferably, n (SiO) of the molecular sieve₂)/n(Al₂O₃) Greater than 21 and less than 60; with P₂O₅The phosphorus content of the molecular sieve is 3-12 wt% based on the dry weight of the molecular sieve; the content of the loaded metal in the molecular sieve is 0.5-3 wt% based on the oxide of the loaded metal and the dry basis weight of the molecular sieve; the Al distribution parameter D of the molecular sieve meets the following requirements: d is more than or equal to 0.65 and less than or equal to 0.82; the proportion of the mesopore volume of the molecular sieve in the total pore volume is 45-65% by volume, and the proportion of the mesopore volume with the pore diameter of 2-20 nm in the total mesopore volume is more than 90% by volume; the ratio of the strong acid amount of the molecular sieve to the total acid amount is 55-70%, and the ratio of the acid amount of the B acid to the acid amount of the L acid is 10-25.

Preferably, the supporting metal is at least one selected from the group consisting of iron, cobalt, nickel, copper, manganese, tin, and bismuth.

Preferably, the first clay is at least one selected from kaolin, sepiolite, attapulgite, rectorite, montmorillonite and diatomite; the second clay is at least one selected from kaolin, metakaolin, diatomite, sepiolite, attapulgite, montmorillonite and rectorite; the other inorganic binder is at least one selected from pseudo-boehmite, alumina sol, silica-alumina sol and water glass.

Preferably, the auxiliary agent also contains P based on the dry weight of the auxiliary agent₂O₅Up to 5 wt% of a phosphorus additive.

Preferably, the adjuvant comprises 8-25 wt% of a phosphorus aluminum inorganic binder, 20-60 wt% of a phosphorus and metal loaded MFI structure molecular sieve, 10-45 wt% of a second clay, 5-25 wt% of other inorganic binders, and 0-3 wt% of a phosphorus additive.

The present disclosure also provides a method for preparing a catalytic cracking aid for increasing propylene yield, the method comprising: mixing the MFI structure molecular sieve containing phosphorus and loaded metal, the phosphorus-aluminum inorganic binder and other inorganic binders, adding or not adding second clay, pulping, and spray-drying; wherein, a phosphorus additive is introduced or not introduced; based on the total dry weight of the preparation raw materials of the auxiliary agent, the preparation raw materials of the auxiliary agent comprise 10-75 wt% of MFI structure molecular sieve containing phosphorus and supported metal based on the dry weight, 3-40 wt% of phosphorus-aluminum inorganic binder based on the dry weight, 1-30 wt% of other inorganic binders based on oxides, 0-60 wt% of second clay based on the dry weight, and the preparation raw materials of the auxiliary agent or the preparation raw materials of the auxiliary agent do not comprise P based on the dry weight₂O₅Up to 5 wt% of a phosphorus additive; wherein the phosphorus-aluminum inorganic binder is phosphorus-aluminum glue and/or phosphorus-aluminum inorganic binder containing first clay, and the phosphorus-aluminum inorganic binder containing first clay comprises Al based on the dry weight of the phosphorus-aluminum inorganic binder containing first clay₂O₃15-40% by weight, calculated as P, of an aluminium component₂O₅45-80 wt% of phosphorus component and more than 0 and not more than 40 wt% of first clay calculated on dry basis weight, and the P/Al weight ratio is 1.0-6.0, pH value is 1-3.5, solid content is 15-60 wt%; n (SiO) of the molecular sieve₂)/n(Al₂O₃) Greater than 18 and less than 70; with P₂O₅The phosphorus content of the molecular sieve is 1-15 wt% based on the dry weight of the molecular sieve; the content of the loaded metal in the molecular sieve is 0.1-5 wt% based on the oxide of the loaded metal and the dry basis weight of the molecular sieve; the Al distribution parameter D of the molecular sieve meets the following requirements: 0.6-0.85, wherein D is Al (S)/Al (C), Al (S) represents the crystal face edge inward H distance of the molecular sieve crystal grain measured by TEM-EDS methodThe aluminum content in a region with the distance of more than 100 square nanometers at random, Al (C) represents the aluminum content in a region with the distance of more than 100 square nanometers at random in the H distance from the geometric center of the crystal face of the molecular sieve crystal grain measured by a TEM-EDS method, wherein the H is 10% of the distance from a certain point on the edge of the crystal face to the geometric center of the crystal face; the proportion of the mesopore volume of the molecular sieve in the total pore volume is 40-70% by volume, and the proportion of the mesopore volume with the pore diameter of 2-20 nm in the total mesopore volume is more than 85% by volume; the ratio of the strong acid amount of the molecular sieve to the total acid amount is 45-75%, and the ratio of the acid amount of the B acid to the acid amount of the L acid is 8-30.

Preferably, the preparation step of the phosphorus-containing and metal-loaded MFI structure molecular sieve comprises: a. desiliconizing the sodium type MFI structure molecular sieve in an alkali solution to obtain a desiliconized molecular sieve; b. performing ammonium exchange on the desiliconized molecular sieve obtained in the step a to obtain an ammonium exchange molecular sieve; wherein the ammonium exchanged molecular sieve has a sodium content of less than 0.2 wt.%, based on sodium oxide and based on total dry basis weight of the ammonium exchanged molecular sieve; c. b, dealuminizing the ammonium exchange molecular sieve obtained in the step b in a composite acid dealuminizing agent solution consisting of fluosilicic acid, organic acid and inorganic acid, and filtering and washing to obtain a dealuminized molecular sieve; d. and c, carrying out phosphorus modification treatment, load metal modification treatment and roasting treatment on the dealuminized molecular sieve obtained in the step c to obtain the MFI structure molecular sieve containing phosphorus and load metal.

Preferably, the preparation step of the sodium MFI structure molecular sieve in step a comprises: filtering and washing MFI structure molecular sieve slurry obtained by amine crystallization to obtain a washed molecular sieve; wherein the sodium content of the water-washed molecular sieve is less than 3.0 wt% based on the total dry basis weight of the water-washed molecular sieve calculated by sodium oxide; and drying and air roasting the water washed molecular sieve to obtain the sodium type MFI structure molecular sieve.

Preferably, the alkali solution in step a is selected from the group consisting of aqueous sodium hydroxide solution, aqueous potassium hydroxide solution and aqueous ammonia.

Preferably, the conditions of the desilication treatment in the step a include: the weight ratio of the sodium type MFI structure molecular sieve, alkali in the alkali solution and water in the alkali solution is 1: (0.1-2): (5-20), wherein the desiliconization treatment temperature is between room temperature and 100 ℃, and the time is 0.2-4 hours.

Preferably, the conditions of the desilication treatment in the step a include: the weight ratio of the sodium type MFI structure molecular sieve, alkali in the alkali solution and water in the alkali solution is 1: (0.2-1): (5-20).

Preferably, the inorganic acid in step c is at least one selected from the group consisting of ethylenediaminetetraacetic acid, oxalic acid, citric acid and sulfosalicylic acid, and the organic acid is at least one selected from the group consisting of hydrochloric acid, sulfuric acid and nitric acid.

Preferably, the dealumination treatment conditions in step c include: the weight ratio of the ammonium exchange molecular sieve, the organic acid, the inorganic acid and the fluosilicic acid is 1: (0.01-0.3): (0.01-0.3): (0.01-0.3); the dealuminization treatment temperature is 25-100 ℃, and the time is 0.5-6 hours.

Preferably, the dealumination treatment conditions in step c include: the weight ratio of the ammonium exchange molecular sieve, the organic acid, the inorganic acid and the fluosilicic acid is 1: (0.03-0.2): (0.015-0.2): (0.015-0.2).

Preferably, the phosphorus modification treatment in step d comprises: at least one phosphorus-containing compound selected from phosphoric acid, ammonium hydrogen phosphate, ammonium dihydrogen phosphate and ammonium phosphate is used to impregnate and/or ion-exchange the molecular sieve.

Preferably, the supported metal modification treatment comprises: a compound containing at least one supported metal selected from the group consisting of iron, cobalt, nickel, copper, manganese, tin and bismuth is used to support the supported metal on a molecular sieve by an impregnation method.

Preferably, the conditions of the calcination treatment include: the atmosphere of the roasting treatment is air atmosphere or water vapor atmosphere; the roasting temperature is 400-800 ℃, and the roasting time is 0.5-8 hours.

Preferably, the preparation step of the first clay-containing aluminophosphate inorganic binder comprises: (1) pulping and dispersing an alumina source, first clay and water into slurry with the solid content of 8-45 wt%; the alumina source is hydrogen capable of being peptized by acidAlumina and/or alumina, first clay on a dry weight basis and Al₂O₃The weight ratio of the alumina source is (more than 0-40) to (15-40); (2) adding concentrated phosphoric acid into the slurry obtained in the step (1) according to the weight ratio of P/Al to 1-6 under stirring; (3) and (3) reacting the slurry obtained in the step (2) at the temperature of 50-99 ℃ for 15-90 minutes.

The catalytic cracking auxiliary agent provided by the disclosure has good catalytic cracking performance, is used for catalytic cracking reaction of hydrocarbon oil after being mixed with a main agent, and can effectively improve propylene yield and propylene selectivity.

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

Detailed Description

The following describes in detail specific embodiments of the present disclosure. 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 present disclosure provides a catalytic cracking assistant for increasing the yield of propylene, which comprises, based on the dry weight of the assistant, 10-75 wt% of phosphorus-containing and metal-loaded MFI structure molecular sieve based on the dry weight, 3-40 wt% of phosphorus-aluminum inorganic binder based on the dry weight, 1-30 wt% of other inorganic binders based on oxides, and 0-60 wt% of second clay based on the dry weight; wherein the phosphorus-aluminum inorganic binder is phosphorus-aluminum glue and/or phosphorus-aluminum inorganic binder containing first clay, and the phosphorus-aluminum inorganic binder containing first clay comprises Al based on the dry weight of the phosphorus-aluminum inorganic binder containing first clay₂O₃15-40% by weight, calculated as P, of an aluminium component₂O₅45-80 wt% of phosphorus component and more than 0 and not more than 40 wt% of first clay calculated on dry basis weight, and the P/Al weight ratio is 1.0-6.0, pH value is 1-3.5, solid content is 15-60 wt%; n (SiO) of the molecular sieve₂)/n(Al₂O₃) Greater than 18 and less than 70; with P₂O₅The phosphorus content of the molecular sieve is 1-15 wt% based on the dry weight of the molecular sieve; calculated as the oxide of the supported metalAnd the content of the loaded metal in the molecular sieve is 0.1-5 wt% based on the dry weight of the molecular sieve; the Al distribution parameter D of the molecular sieve meets the following requirements: d is more than or equal to 0.6 and less than or equal to 0.85, wherein D is Al (S)/Al (C), Al (S) represents the aluminum content of a region which is arbitrarily more than 100 square nanometers in the inward H distance of the crystal face edge of the molecular sieve crystal grain measured by a TEM-EDS method, Al (C) represents the aluminum content of a region which is arbitrarily more than 100 square nanometers in the outward H distance of the geometric center of the crystal face of the molecular sieve crystal grain measured by the TEM-EDS method, wherein H is 10 percent of the distance from a certain point of the crystal face edge to the geometric center of the crystal face; the proportion of the mesopore volume of the molecular sieve in the total pore volume is 40-70% by volume, and the proportion of the mesopore volume with the pore diameter of 2-20 nm in the total mesopore volume is more than 85% by volume; the ratio of the strong acid amount of the molecular sieve to the total acid amount is 45-75%, and the ratio of the acid amount of the B acid to the acid amount of the L acid is 8-30. Preferably, n (SiO) of the molecular sieve₂)/n(Al₂O₃) Greater than 21 and less than 60; with P₂O₅The phosphorus content of the molecular sieve is 3-12 wt% based on the dry weight of the molecular sieve; the content of the loaded metal in the molecular sieve is 0.5-3 wt% based on the oxide of the loaded metal and the dry basis weight of the molecular sieve; the Al distribution parameter D of the molecular sieve meets the following requirements: d is more than or equal to 0.65 and less than or equal to 0.82; the proportion of the mesopore volume of the molecular sieve in the total pore volume is 45-65% by volume, and the proportion of the mesopore volume with the pore diameter of 2-20 nm in the total mesopore volume is more than 90% by volume; the ratio of the strong acid amount of the molecular sieve to the total acid amount is 55-70%, and the ratio of the acid amount of the B acid to the acid amount of the L acid is 10-25.

According to the present disclosure, the aluminophosphate inorganic binder is a aluminophosphate inorganic binder and/or a aluminophosphate gel comprising a first clay.

In one embodiment, the phosphorus-aluminum inorganic binder comprises Al based on the dry weight of the phosphorus-aluminum inorganic binder₂O₃15-40% by weight, calculated as P, of an aluminium component₂O₅45-80 wt% of phosphorus component and 0-40 wt% of first clay calculated by dry basis weight, and the P/Al weight ratio is 1.0-6.0, pH value is 1-3.5, and solid content is 15-60 wt%; for example, including Al₂O₃15-40% by weight, calculated as P, of an aluminium component₂O₅45-80 wt% of a phosphorus component and 1-40 wt% of a first clay, based on dry weight; preferably contains Al₂O₃15-35% by weight, calculated as P, of an aluminium component₂O₅A phosphorus component in an amount of 50 to 75 wt% and a first clay in an amount of 8 to 35 wt% on a dry basis, preferably having a P/Al weight ratio of 1.2 to 6.0, more preferably 2.0 to 5.0, and a pH value of 1.5 to 3.0.

In another embodiment, the phosphorus aluminum inorganic binder comprises Al based on the dry weight of the phosphorus aluminum inorganic binder₂O₃20-40% by weight, calculated as P, of an aluminium component₂O₅60-80% by weight of a phosphorus component.

The MFI structure is the topology of the molecular sieve, for example ZSM-5 molecular sieve has the MFI structure.

According to the present disclosure, the supported metal refers to a metal supported on the molecular sieve by a supporting method, and does not include aluminum and alkali metals such as sodium and potassium, and may include at least one selected from iron, cobalt, nickel, copper, manganese, tin and bismuth, and may also include other metals, and the present disclosure is not limited thereto.

In light of the present disclosure, it is well known to those skilled in the art to determine the aluminum content of the molecular sieve by using the TEM-EDS method, wherein the geometric center is also well known to those skilled in the art, and can be calculated according to a formula, which is not repeated in the present disclosure, and the geometric center of the general symmetric graph is the intersection point of the connecting lines of the respective opposite vertices, for example, the geometric center of the hexagonal crystal plane of the conventional hexagonal plate-shaped ZSM-5 is at the intersection point of the connecting lines of the three opposite vertices. The crystal plane is a plane of regular crystal grains, and the inward and outward directions are both inward and outward directions on the crystal plane.

In accordance with the present disclosure, the ratio of mesopore volume to total pore volume and the ratio of mesopore volume having a pore diameter of from 2nm to 20nm to total mesopore volume of the molecular sieve are measured using the nitrogen adsorption BET specific surface area method, the mesopore volume generally referring to the pore volume having a pore diameter of greater than 2nm and less than 100 nm; the ratio of the strong acid amount of the molecular sieve to the total acid amount isBy NH₃The TPD method, the acid centre of which may be NH₃Desorbing the corresponding acid center at the temperature of more than 300 ℃; and the ratio of the acid amount of the B acid to the acid amount of the L acid is measured by adopting a pyridine adsorption infrared acidity method.

Clays are well known to those skilled in the art in light of this disclosure, and the first clay may be at least one selected from the group consisting of kaolin, sepiolite, attapulgite, rectorite, montmorillonite and diatomaceous earth, preferably including rectorite, more preferably rectorite; the second clay may be at least one selected from kaolin, metakaolin, sepiolite, attapulgite, montmorillonite, rectorite, diatomaceous earth, halloysite, saponite, bentonite and hydrotalcite, preferably at least one selected from kaolin, metakaolin, diatomaceous earth, sepiolite, attapulgite, montmorillonite and rectorite; the additional inorganic binder may be selected from one or more of the inorganic oxide binders conventionally used in catalytic cracking promoters or catalyst binder components other than the aluminophosphate and aluminophosphate inorganic binders, preferably from at least one of pseudoboehmite, alumina sol, silica alumina sol, and water glass, more preferably from at least one of pseudoboehmite and alumina sol.

In accordance with the present disclosure, the first clay-containing aluminophosphate inorganic binder preferably contains Al₂O₃15-35% by weight, calculated as P, of an aluminium component₂O₅A phosphorus component in an amount of 50 to 75 wt% and a first clay in an amount of 8 to 35 wt% on a dry basis, preferably having a P/Al weight ratio of 1.2 to 6.0, more preferably 2.0 to 5.0, and a pH value of 1.0 to 3.5.

According to the disclosure, the adjuvant may further comprise P on a dry weight basis₂O₅Up to 5 wt% of a phosphorus additive. The phosphorus additive may be selected from phosphorus compounds, such as one or more of inorganic and organic compounds comprising phosphorus, which may be readily water soluble, or which may be poorly water soluble or insoluble, such as phosphorus oxides, phosphoric acid, orthophosphates, phosphites, hypophosphites, basic phosphates, acid phosphates, and phosphorus-containing organic compoundsOne or more of the compounds. Preferred phosphorus compounds are one or more of phosphoric acid, ammonium phosphate, ammonium dihydrogen phosphate, diammonium hydrogen phosphate and aluminum phosphate. The resulting adjuvant has a phosphorus additive in the form of a phosphorus compound such as phosphorus oxide, orthophosphate, phosphite, basic phosphate and acid phosphate. The phosphorus additive may be present in any location where a promoter may be present, such as inside the channels of the zeolite, on the surface of the zeolite, in the matrix material (i.e., a material other than the molecular sieve in the promoter), and may be present both inside the channels of the zeolite, on the surface of the zeolite, and in the matrix material. The phosphorus additive is not included in the content of phosphorus in the molecular sieve, nor is the phosphorus introduced by the phosphorus-aluminum inorganic binder included.

In accordance with the present disclosure, the adjuvant preferably comprises 8-25 wt.% of a phosphorus aluminum inorganic binder, 20-60 wt.% of a phosphorus and metal loaded MFI structure molecular sieve, 10-45 wt.% of a second clay, 5-25 wt.% of other inorganic binders, and 0-3 wt.% of a phosphorus additive.

The present disclosure also provides a method for preparing a catalytic cracking aid for increasing propylene yield, the method comprising: mixing the MFI structure molecular sieve containing phosphorus and loaded metal, the phosphorus-aluminum inorganic binder and other inorganic binders, adding or not adding second clay, pulping, and spray-drying; wherein, a phosphorus additive is introduced or not introduced; based on the total dry weight of the preparation raw materials of the auxiliary agent, the preparation raw materials of the auxiliary agent comprise 10-75 wt% of MFI structure molecular sieve containing phosphorus and supported metal based on the dry weight, 3-40 wt% of phosphorus-aluminum inorganic binder based on the dry weight, 1-30 wt% of other inorganic binders based on oxides, 0-60 wt% of second clay based on the dry weight, and the preparation raw materials of the auxiliary agent or the preparation raw materials of the auxiliary agent do not comprise P based on the dry weight₂O₅Up to 5 wt% of a phosphorus additive; wherein the phosphorus-aluminum inorganic binder is phosphorus-aluminum glue and/or phosphorus-aluminum inorganic binder containing first clay, and the phosphorus-aluminum inorganic binder containing first clay comprises Al based on the dry weight of the phosphorus-aluminum inorganic binder containing first clay₂O₃15-40% by weight, calculated as P, of an aluminium component₂O₅45-80 wt% of phosphorus component and more than 0 and not more than 40 wt% of first clay calculated on dry basis weight, and the P/Al weight ratio is 1.0-6.0, pH value is 1-3.5, solid content is 15-60 wt%; n (SiO) of the molecular sieve₂)/n(Al₂O₃) Greater than 18 and less than 70; with P₂O₅The phosphorus content of the molecular sieve is 1-15 wt% based on the dry weight of the molecular sieve; the content of the loaded metal in the molecular sieve is 0.1-5 wt% based on the oxide of the loaded metal and the dry basis weight of the molecular sieve; the Al distribution parameter D of the molecular sieve meets the following requirements: d is more than or equal to 0.6 and less than or equal to 0.85, wherein D is Al (S)/Al (C), Al (S) represents the aluminum content of a region which is arbitrarily more than 100 square nanometers in the inward H distance of the crystal face edge of the molecular sieve crystal grain measured by a TEM-EDS method, Al (C) represents the aluminum content of a region which is arbitrarily more than 100 square nanometers in the outward H distance of the geometric center of the crystal face of the molecular sieve crystal grain measured by the TEM-EDS method, wherein H is 10 percent of the distance from a certain point of the crystal face edge to the geometric center of the crystal face; the proportion of the mesopore volume of the molecular sieve in the total pore volume is 40-70% by volume, and the proportion of the mesopore volume with the pore diameter of 2-20 nm in the total mesopore volume is more than 85% by volume; the ratio of the strong acid amount of the molecular sieve to the total acid amount is 45-75%, and the ratio of the acid amount of the B acid to the acid amount of the L acid is 8-30.

According to the present disclosure, the steps of preparing the phosphorus-containing and metal-loaded MFI structure molecular sieve may include: a. desiliconizing the sodium type MFI structure molecular sieve in an alkali solution to obtain a desiliconized molecular sieve; b. performing ammonium exchange on the desiliconized molecular sieve obtained in the step a to obtain an ammonium exchange molecular sieve; wherein the ammonium exchanged molecular sieve has a sodium content of less than 0.2 wt.%, based on sodium oxide and based on total dry basis weight of the ammonium exchanged molecular sieve; c. b, dealuminizing the ammonium exchange molecular sieve obtained in the step b in a composite acid dealuminizing agent solution consisting of fluosilicic acid, organic acid and inorganic acid, and filtering and washing to obtain a dealuminized molecular sieve; d. and c, carrying out phosphorus modification treatment, load metal modification treatment and roasting treatment on the dealuminized molecular sieve obtained in the step c to obtain the MFI structure molecular sieve containing phosphorus and load metal.

The sodium MFI structure molecular sieves are well known to those skilled in the art in light of this disclosure and can be obtained without amine crystallization or after calcination of molecular sieves prepared by a templating method, e.g., ZSM-5 molecular sieves having a silica to alumina ratio of less than 80. The preparation step of the sodium type MFI structure molecular sieve in the step a can comprise the following steps: filtering and washing MFI structure molecular sieve slurry obtained by amine crystallization to obtain a washed molecular sieve; wherein the sodium content of the water-washed molecular sieve is less than 3.0 wt% based on the total dry basis weight of the water-washed molecular sieve calculated by sodium oxide; and drying and air roasting the water washed molecular sieve to obtain the sodium type MFI structure molecular sieve. The air roasting is used for removing the template agent in the water-washed molecular sieve, and the temperature of the air roasting can be 400-700 ℃, and the time can be 0.5-10 hours.

According to the present disclosure, the desiliconization treatment is used to remove part of the framework silicon atoms of the molecular sieve, resulting in more secondary pores, and the alkali solution in step a may be at least one selected from the group consisting of an aqueous sodium hydroxide solution, an aqueous potassium hydroxide solution and aqueous ammonia, preferably an aqueous sodium hydroxide solution; the conditions of the desiliconization treatment in step a may include: the weight ratio of the sodium type MFI structure molecular sieve, alkali in the alkali solution and water in the alkali solution is 1: (0.1-2): (5-20), preferably 1: (0.2-1): (5-20), wherein the desiliconization treatment temperature is between room temperature and 100 ℃, and the time is 0.2-4 hours.

Ammonium exchange is well known to those skilled in the art in light of this disclosure for reducing the sodium content of molecular sieves. For example, the conditions for the ammonium exchange may include: according to the molecular sieve: ammonium salt: water 1: (0.1-1): (5-15) filtering after ammonium exchange of the molecular sieve at room temperature to 100 ℃ for 0.5-3 hours, wherein the ammonium salt used may be a commonly used inorganic ammonium salt, for example, at least one selected from ammonium chloride, ammonium sulfate and ammonium nitrate, and the number of ammonium exchanges may be repeated 1-3 times until the sodium oxide content in the molecular sieve is less than 0.2 wt%.

According to the present disclosure, although the desiliconization treatment can obtain the MFI structure molecular sieve with secondary pores, the surface of the molecular sieve is relatively rich in aluminum, the reaction on the outer surface is increased, the shape selection performance of the MFI structure molecular sieve is weakened, and the improvement of the reaction selectivity is not facilitated, so that the subsequent dealumination treatment is required. Dealumination treatments are well known to those skilled in the art, but the use of inorganic acids, organic acids and fluosilicic acid together for dealumination treatments has not been reported. The dealumination treatment can be carried out once or for multiple times, organic acid can be firstly mixed with the ammonium exchange molecular sieve, and then fluosilicic acid and inorganic acid are mixed with the ammonium exchange molecular sieve, namely, the organic acid is firstly added into the ammonium exchange molecular sieve, and then the fluosilicic acid and the inorganic acid are slowly and concurrently added, or the fluosilicic acid is firstly added and then the inorganic acid is added, preferably the fluosilicic acid and the inorganic acid are slowly and concurrently added. For example, the organic acid in step c may be at least one selected from the group consisting of ethylenediaminetetraacetic acid, oxalic acid, citric acid and sulfosalicylic acid, preferably oxalic acid or citric acid, and more preferably oxalic acid; the inorganic acid may be at least one selected from hydrochloric acid, sulfuric acid and nitric acid, preferably hydrochloric acid or sulfuric acid, and more preferably hydrochloric acid; the dealumination treatment conditions may include: the weight ratio of the ammonium exchange molecular sieve, the organic acid, the inorganic acid and the fluosilicic acid is 1: (0.01-0.3): (0.01-0.3): (0.01-0.3), preferably 1: (0.03-0.2): (0.015-0.2): (0.015-0.2); the dealuminization treatment temperature is 25-100 ℃, and the time is 0.5-6 hours. The MFI structure molecular sieve is treated by combining desiliconization treatment and composite acid dealuminization treatment, the aluminum distribution, the silicon-aluminum ratio, the acid property and the pore structure of the molecular sieve are modulated, so that the MFI structure molecular sieve still has good shape selectivity after pore-expanding modification, and the yield of propylene, ethylene and BTX of the MFI structure molecular sieve is effectively improved.

Phosphorus modification treatments are well known to those skilled in the art in light of this disclosure, for example, the phosphorus modification treatment in step d may include: at least one phosphorus-containing compound selected from phosphoric acid, ammonium hydrogen phosphate, ammonium dihydrogen phosphate and ammonium phosphate is used to impregnate and/or ion-exchange the molecular sieve.

According to the present disclosure, the supporting treatment of the supported metal is well known to those skilled in the art, and means that the supported metal is supported on the molecular sieve by a supporting method, for example, a compound containing at least one supported metal selected from iron, cobalt, nickel, copper, manganese, tin and bismuth may be supported on the molecular sieve by an impregnation method; the loading method may also include other common metal loading methods, and the disclosure is not limited.

Calcination treatments are well known to those skilled in the art in light of this disclosure, and the conditions of the calcination treatment may include, for example: the atmosphere of the roasting treatment is air atmosphere or water vapor atmosphere; the roasting temperature is 400-800 ℃, and the roasting time is 0.5-8 hours.

Washing as described herein is well known to those skilled in the art and generally refers to water washing, e.g., the molecular sieve may be rinsed with water at 30-60 c 5-10 times the weight of the molecular sieve.

According to the present disclosure, the step of preparing the first clay-containing aluminophosphate inorganic binder may comprise: (1) pulping and dispersing an alumina source, first clay and water into slurry with the solid content of 8-45 wt%; the alumina source is aluminum hydroxide and/or aluminum oxide which can be peptized by acid, first clay and Al which are calculated by dry weight₂O₃The weight ratio of the alumina source is (more than 0-40) to (15-40); (2) adding concentrated phosphoric acid into the slurry obtained in the step (1) according to the weight ratio of P/Al to 1-6 under stirring; wherein P in the P/Al is the weight of phosphorus in the phosphoric acid by simple substance, and Al is the weight of aluminum in the alumina source by simple substance; (3) and (3) reacting the slurry obtained in the step (2) at the temperature of 50-99 ℃ for 15-90 minutes.

According to the present disclosure, the alumina source may be at least one selected from the group consisting of rho-alumina, chi-alumina, eta-alumina, gamma-alumina, kappa-alumina, delta-alumina, theta-alumina, gibbsite, metazoite, nordstrandite, diaspore, boehmite, and pseudoboehmite from which the aluminum component of the first clay-containing aluminophosphate inorganic binder is derived. The first clay can be one or more of kaolin, sepiolite, attapulgite, rectorite, montmorillonite and diatomite, and preferably rectorite. The concentrated phosphoric acid may be present in a concentration of 60 to 98 wt.%, more preferably 75 to 90 wt.%. The feeding rate of phosphoric acid is preferably 0.01 to 0.10Kg of phosphoric acid per minute per Kg of alumina source, and more preferably 0.03 to 0.07Kg of phosphoric acid per minute per Kg of alumina source.

According to the disclosure, due to the introduction of the clay, the phosphorus-aluminum inorganic binder containing the first clay not only improves mass transfer and heat transfer among materials in the preparation process, but also avoids binder solidification caused by nonuniform local instant violent reaction of the materials, heat release and overtemperature, and the obtained binder has the same binding performance as the phosphorus-aluminum binder prepared by a method without introducing the clay; in addition, the method introduces clay, especially rectorite with a layered structure, improves the heavy oil conversion capability of the catalyst composition, and enables the obtained auxiliary agent to have better selectivity.

The preparation method of the catalytic cracking assistant provided by the present disclosure mixes and pulps the phosphorus-and metal-loaded MFI structure molecular sieve, the phosphorus-aluminum inorganic binder and other inorganic binders, and the order of addition thereof has no special requirement, for example, the phosphorus-aluminum inorganic binder, other inorganic binders, the molecular sieve and the second clay can be mixed (when the second clay is not contained, the relevant addition step can be omitted) and then pulped, preferably, the second clay, the molecular sieve and other inorganic binders are mixed and pulped before adding the phosphorus-aluminum inorganic binder, which is beneficial to improving the activity and selectivity of the assistant.

The preparation method of the catalytic cracking assistant provided by the disclosure further comprises the step of spray drying the slurry obtained by pulping. Methods of spray drying are well known to those skilled in the art and no particular requirement of the present disclosure exists.

When the promoter contains the phosphorus additive, the phosphorus additive can be introduced by one of the following methods or a combination of several methods, but is not limited to the methods for introducing the phosphorus additive into the promoter:

1. adding a phosphorus compound to the slurry before the spray drying and forming of the auxiliary agent;

2. after the spray drying and forming of the auxiliary agent, the phosphorus compound is impregnated or chemically adsorbed, and the phosphorus compound is introduced through solid-liquid separation (if needed), drying and roasting processes, wherein the drying temperature can be between room temperature and 400 ℃, preferably 100-300 ℃, the roasting temperature can be between 400-700 ℃, preferably 450-650 ℃, and the roasting time can be between 0.5 and 100 hours, preferably between 0.5 and 10 hours. The phosphorus compound may be selected from one or more of various inorganic and organic compounds of phosphorus. The phosphorus compound may be either readily water-soluble or poorly water-soluble or water-insoluble. Examples of the phosphorus compound include oxides of phosphorus, phosphoric acid, orthophosphates, phosphites, hypophosphites, phosphorus-containing organic compounds, and the like. Preferred phosphorus compounds are selected from one or more of phosphoric acid, ammonium phosphate, ammonium dihydrogen phosphate, diammonium hydrogen phosphate, aluminum phosphate and the like.

Thus, the phosphorus additive may be present in any location where an adjunct may be present, such as may be present inside the pores of the zeolite, on the surface of the zeolite, in the matrix material, and may also be present both inside the pores of the zeolite, on the surface of the zeolite and in the matrix material. The phosphorus additive is present in the form of a phosphorus compound (e.g., an oxide of phosphorus, an orthophosphate, a phosphite, a basic phosphate, an acid phosphate).

The catalytic cracking auxiliary agent provided by the disclosure is suitable for catalytic cracking of various hydrocarbon oils. When the catalyst is used in the catalytic cracking process, the catalyst can be added into a catalytic cracking reactor independently or can be mixed with a catalytic cracking catalyst for use. In general, the adjunct provided by the present disclosure comprises no more than 30 wt%, preferably 1 to 25 wt%, more preferably 3 to 15 wt% of the total amount of FCC catalyst and adjunct mixture provided by the present disclosure, and the hydrocarbon oil is selected from one or more of various petroleum fractions, such as crude oil, atmospheric residue, vacuum residue, atmospheric wax oil, vacuum wax oil, straight run wax oil, propane light/heavy deoiling, coker wax oil, and coal liquefaction products. The hydrocarbon oil may contain heavy metal impurities such as nickel and vanadium, and sulfur and nitrogen impurities, for example, the content of sulfur may be as high as 3.0 wt%, the content of nitrogen may be as high as 2.0 wt%, and the content of metal impurities such as vanadium and nickel may be as high as 3000 ppm.

The catalytic cracking auxiliary agent provided by the disclosure is used in a catalytic cracking process, and the catalytic cracking conditions of the hydrocarbon oil can be conventional catalytic cracking conditions. Generally, the hydrocarbon oil catalytic cracking conditions include: the reaction temperature is 400-600 ℃, the preferred temperature is 450-550 ℃, and the weight hourly space velocity is 8-120 h^-1Preferably 8 to 80 hours^-1The ratio of the solvent to the oil (weight ratio) is 1-20, preferably 3-15. The catalytic cracking auxiliary agent provided by the present disclosure can be used in various existing catalytic cracking reactors, such as in fixed bed reactors, fluidized bed reactors, riser reactors, multi-reaction zone reactors, and the like.

The present disclosure is further illustrated by the following examples, which are not intended to be limiting and the instruments and reagents used in the examples of the present disclosure are those commonly used by those skilled in the art unless otherwise specified.

The crystallinity of the present disclosure is determined using the standard method of ASTM D5758-2001(2011) e 1.

N (SiO) of the present disclosure₂)/n(Al₂O₃) Namely, the silicon-aluminum ratio is calculated by the contents of silicon oxide and aluminum oxide, and the contents of the silicon oxide and the aluminum oxide are measured by the GB/T30905-2014 standard method.

The phosphorus content of the alloy is determined by a GB/T30905-2014 standard method, and the content of the load metal is determined by the GB/T30905-2014 standard method.

See methods for solid catalyst investigation, petrochemical, 29(3), 2000: 227.

total specific surface (S) of the present disclosure_BET) Mesopore pore volume, total pore volume, and mesopore pore volume of 2-20 nm were measured by AS-3, AS-6 static nitrogen adsorption apparatus manufactured by Quantachrome instruments. The instrument parameters are as follows: the sample was placed in a sample handling system and evacuated to 1.33X 10 at 300 deg.C^-2Pa, keeping the temperature and the pressure for 4h, and purifying the sample. Testing the purified samples at different specific pressures P/P at a liquid nitrogen temperature of-196 DEG C₀The adsorption quantity and the desorption quantity of the nitrogen under the condition are obtained to obtain N₂Adsorption-desorption isotherm curve. Then the total specific surface is calculated by utilizing a two-parameter BET formulaSpecific surface area of product, micropore and mesopore, and taking specific pressure P/P₀The adsorption amount was 0.98 or less as the total pore volume of the sample, the pore size distribution of the mesopore portion was calculated using BJH formula, and the mesopore pore volume (2 to 100 nm) and the mesopore pore volume of 2 to 20nm were calculated by the integration method.

The acid content and total acid content of the strong acid disclosed by the disclosure are measured by an Autochem II 2920 temperature programmed desorption instrument of Michman, USA. And (3) testing conditions are as follows: weighing 0.2g of a sample to be detected, putting the sample into a sample tube, putting the sample tube into a thermal conductivity cell heating furnace, taking He gas as carrier gas (50mL/min), heating the sample tube to 600 ℃ at the speed of 20 ℃/min, and purging the sample tube for 60min to remove impurities adsorbed on the surface of the catalyst. Then cooling to 100 ℃, keeping the temperature for 30min, and switching to NH₃-He mixed gas (10.02% NH)₃+ 89.98% He) for 30min, and then continuing to purge with He gas for 90min until the baseline is stable, so as to desorb the physically adsorbed ammonia gas. And (4) heating to 600 ℃ at the heating rate of 10 ℃/min for desorption, keeping for 30min, and finishing desorption. Detecting gas component change by TCD detector, automatically integrating by instrument to obtain total acid amount and strong acid amount, wherein acid center of strong acid is NH₃The desorption temperature is higher than 300 ℃ of the corresponding acid center.

The amount of acid B and the amount of acid L of the present disclosure were measured by FTS3000 Fourier Infrared Spectroscopy manufactured by BIO-RAD, USA. And (3) testing conditions are as follows: pressing the sample into tablet, sealing in an in-situ cell of an infrared spectrometer, and vacuumizing to 10 deg.C at 350 deg.C^-3Pa, keeping for 1h to enable gas molecules on the surface of the sample to be desorbed completely, and cooling to room temperature. Introducing pyridine vapor with pressure of 2.67Pa into the in-situ tank, balancing for 30min, heating to 200 deg.C, and vacuumizing to 10 deg.C^-3Pa, keeping for 30min, cooling to room temperature at 1400-1700cm^-1Scanning in wave number range, and recording infrared spectrogram of pyridine adsorption at 200 ℃. Then the sample in the infrared absorption cell is moved to a heat treatment area, the temperature is raised to 350 ℃, and the vacuum is pumped to 10 DEG^-3Pa, keeping for 30min, cooling to room temperature, and recording the infrared spectrogram of pyridine adsorption at 350 ℃. And automatically integrating by an instrument to obtain the acid content of the B acid and the acid content of the L acid.

The sodium content of the present disclosure is determined using the GB/T30905-2014 standard method.

The D value is calculated as follows: selecting a crystal grain and a certain crystal face of the crystal grain in a transmission electron mirror to form a polygon, wherein the polygon has a geometric center, an edge and a 10% distance H (different edge points and different H values) from the geometric center to a certain point of the edge, any one of regions in the inward H distance of the edge of the crystal face which is larger than 100 square nanometers and any one of regions in the outward H distance of the geometric center of the crystal face which is larger than 100 square nanometers are respectively selected, measuring the aluminum content, namely Al (S1) and Al (C1), calculating D1 to Al (S1)/Al (C1), respectively selecting different crystal grains to measure for 5 times, and calculating the average value to be D.

When the auxiliary agent disclosed by the invention is used for evaluating the performance of catalytic cracking reaction, a reaction product is N₂Carrying out gas-liquid separation in a liquid receiving bottle at the temperature of minus 10 ℃, and collecting a gas product to finish on-line analysis by an Agilent 6890GC (TCD detector); collecting liquid products, weighing off-line, and performing simulated distillation and gasoline monomer hydrocarbon analysis (testing by RIPP81-90 testing method) respectively, wherein the cut points of gasoline and diesel oil are 221 ℃ and 343 ℃ respectively; the coke-forming catalyst is burnt and regenerated on line, and the coke mass is calculated according to the flow rate and the composition of the flue gas; the mass balance was calculated by summing all product masses.

The RIPP standard method disclosed in the disclosure can be found in petrochemical analysis methods, edition such as Yangcui, 1990 edition.

Some of the raw materials used in the examples had the following properties:

the pseudoboehmite is an industrial product produced by Shandong aluminum industry company, and the solid content is 60 percent by weight; the aluminum sol is an industrial product, Al, produced by the Qilu division of the medium petrochemical catalyst₂O₃The content was 21.5 wt%; the silica sol is an industrial product, SiO, produced by the middle petrochemical catalyst Qilu division₂The content was 28.9% by weight, Na₂The O content is 8.9 percent; the kaolin is kaolin specially used for a catalytic cracking catalyst produced by Suzhou kaolin company, and the solid content is 78 weight percent. Hydrochloric acid concentration of 36 wt%, rectorite as product of Hubei Zhongxiang famous flow rectorite development Limited company, and quartz sand content<3.5 wt.% of Al₂O₃39.0 wt.% of Fe₂O₃The content of Na was 2.0 wt%₂The O content was 0.03% by weight, and the solid content was 77% by weight; SB aluminum hydroxide powder: al from Condex, Germany₂O₃The content was 75% by weight; gamma-alumina powder: al from Condex, Germany₂O₃The content was 95% by weight. Hydrochloric acid: chemical purity, concentration of 36-38 wt%, and is produced in Beijing chemical plant.

Examples 1-3 provide phosphorus-and metal-loaded MFI structure molecular sieves of the present disclosure, and comparative examples 1-10 provide comparative molecular sieves.

Example 1

Crystallizing ZSM-5 molecular sieve (produced by catalyst Qilu division, amine-free synthesis, n (SiO)₂)/n(Al₂O₃) 27) the mother liquor was filtered off and washed with water to Na₂The content of O is lower than 3.0 weight percent, and a filter cake is obtained by filtration; adding 100g (dry basis) of the molecular sieve into 1000g of 2.0% NaOH solution, heating to 65 ℃, reacting for 30min, rapidly cooling to room temperature, filtering, and washing until the filtrate is neutral. Then, the filter cake was added to 800g of water and slurried, 40g of NH was added₄Cl, heating to 75 ℃, and carrying out exchange treatment for 1h until Na₂The O content is lower than 0.2 weight percent, and a molecular sieve filter cake is obtained after filtering and washing; taking 50g (dry basis) of the molecular sieve, adding water to prepare molecular sieve slurry with the solid content of 10 weight percent, adding 4g of oxalic acid while stirring, then adding 45g of hydrochloric acid (with the mass fraction of 10%) and 30g of fluosilicic acid (with the mass fraction of 3%) in a concurrent flow manner, and adding for 30 min; heating to 65 ℃, stirring for 1h at constant temperature, filtering and washing until the filtrate is neutral; adding water into the filter cake, pulping to obtain molecular sieve slurry with solid content of 40 wt%, adding 6.3g H₃PO₄(concentration 85% by weight) and 2.5gCu (NO)₃)₂·3H₂And O, uniformly mixing, soaking, drying and roasting at 550 ℃ for 2 hours. The molecular sieve A is obtained, and the physicochemical properties are shown in Table 1.

Comparative example 1

Crystallizing ZSM-5 molecular sieve (produced by catalyst Qilu division, amine-free synthesis, n (SiO)₂)/n(Al₂O₃) 27) the mother liquor was filtered off and washed with water to Na₂The content of O is lower than 3.0 weight percent, and a filter cake is obtained by filtration; taking 100g (dry basis) of the molecular sieve, adding 1000g of 2.0 percent NaOH solution, heating to 65 ℃, reacting for 30min, quickly cooling to room temperature, filtering, and washing until the filtrate is neutral. Then, the filter cake was added to 800g of water and slurried, 40g of NH was added₄Cl, heating to 75 ℃, and carrying out exchange treatment for 1h until Na₂The O content is lower than 0.2 weight percent, and a molecular sieve filter cake is obtained after filtering and washing; taking 50g (dry basis) of the molecular sieve, adding water to prepare molecular sieve slurry with the solid content of 10 weight percent, and adding 27g of oxalic acid while stirring; heating to 65 ℃, stirring for 1h at constant temperature, filtering and washing until the filtrate is neutral; adding water into the filter cake, pulping to obtain molecular sieve slurry with solid content of 40 wt%, adding 6.3gH₃PO₄(concentration 85% by weight) and 2.5gCu (NO)₃)₂·3H₂And O, uniformly mixing, soaking, drying and roasting at 550 ℃ for 2 hours. Molecular sieve DA1 was obtained, and the physicochemical properties are shown in Table 1.

Comparative example 2

Crystallizing ZSM-5 molecular sieve (produced by catalyst Qilu division, amine-free synthesis, n (SiO)₂)/n(Al₂O₃) 27) the mother liquor was filtered off and washed with water to Na₂The content of O is lower than 3.0 weight percent, and a filter cake is obtained by filtration; adding 100g (dry basis) of the molecular sieve into 1000g of 2.2% NaOH solution, heating to 65 ℃, reacting for 30min, rapidly cooling to room temperature, filtering, and washing until the filtrate is neutral. Then, 50g (dry basis) of the molecular sieve is taken and added with water to prepare molecular sieve slurry with the solid content of 10 weight percent, and 215g of hydrochloric acid (the mass fraction is 10 percent) is added during stirring; heating to 65 ℃, stirring for 1h at constant temperature, filtering and washing until the filtrate is neutral; adding 1500g of water into the filter cake, pulping, adding 80g of NH₄Heating Cl to 65 ℃, exchanging and washing for 40min, filtering, and leaching until the filtrate is neutral; adding water into the filter cake, pulping to obtain molecular sieve slurry with solid content of 40 wt%, adding 6.3gH₃PO₄(concentration 85% by weight) and 2.5gCu (NO)₃)₂·3H₂And O, uniformly mixing, soaking, drying and roasting at 550 ℃ for 2 hours. Molecular sieve DA2 was obtained, and the physicochemical properties are shown in Table 1.

Comparative example 3

Crystallizing ZSM-5 molecular sieve (produced by catalyst Qilu division, amine-free synthesis, n (SiO)₂)/n(Al₂O₃) 27) tooFiltering off the mother liquor, and washing with water to Na₂The content of O is lower than 3.0 weight percent, and a filter cake is obtained by filtration; adding 100g (dry basis) of the molecular sieve into 1000g of 2.2% NaOH solution, heating to 65 ℃, reacting for 30min, rapidly cooling to room temperature, filtering, and washing until the filtrate is neutral. Then, the filter cake was added to 800g of water and slurried, 40g of NH was added₄Cl, heating to 75 ℃, and carrying out exchange treatment for 1h until Na₂The O content is lower than 0.2 weight percent, and a molecular sieve filter cake is obtained after filtering and washing; taking 50g (dry basis) of the molecular sieve, adding water to prepare molecular sieve slurry with the solid content of 10 weight percent, adding 135g (mass fraction of 3%) of fluosilicic acid while stirring, and adding for 30 min; heating to 65 ℃, stirring for 1h at constant temperature, filtering and washing until the filtrate is neutral; adding water into the filter cake, pulping to obtain molecular sieve slurry with solid content of 40 wt%, adding 6.3gH₃PO₄(concentration 85% by weight) and 2.5gCu (NO)₃)₂·3H₂And O, uniformly mixing, soaking, drying and roasting at 550 ℃ for 2 hours. Molecular sieve DA3 was obtained, and the physicochemical properties are shown in Table 1.

Comparative example 4

Crystallizing ZSM-5 molecular sieve (produced by catalyst Qilu division, amine-free synthesis, n (SiO)₂)/n(Al₂O₃) 27) the mother liquor was filtered off and washed with water to Na₂The content of O is lower than 3.0 weight percent, and a filter cake is obtained by filtration; adding 100g (dry basis) of the molecular sieve into 1000g of 1.9% NaOH solution, heating to 65 ℃, reacting for 30min, rapidly cooling to room temperature, filtering, and washing until the filtrate is neutral. Then, the filter cake was added to 800g of water and slurried, 40g of NH was added₄Cl, heating to 75 ℃, and carrying out exchange treatment for 1h until Na₂The O content is lower than 0.2 weight percent, and a molecular sieve filter cake is obtained after filtering and washing; taking 50g (dry basis) of the molecular sieve, adding water to prepare molecular sieve slurry with the solid content of 10 weight percent, adding 11g of oxalic acid while stirring, then adding 110g of hydrochloric acid (the mass fraction is 10 percent), and adding for 30 min; heating to 65 ℃, stirring for 1h at constant temperature, filtering and washing until the filtrate is neutral; adding water into the filter cake, pulping to obtain molecular sieve slurry with solid content of 40 wt%, adding 6.3gH₃PO₄(concentration 85% by weight) and 2.5gCu (NO)₃)₂·3H₂O, evenly mixing, soaking, drying and roasting at 550 DEG CFor 2 hours. Molecular sieve DA4 was obtained, and the physicochemical properties are shown in Table 1.

Comparative example 5

Crystallizing ZSM-5 molecular sieve (produced by catalyst Qilu division, amine-free synthesis, n (SiO)₂)/n(Al₂O₃) 27) the mother liquor was filtered off and washed with water to Na₂The content of O is lower than 3.0 weight percent, and a filter cake is obtained by filtration; adding 100g (dry basis) of the molecular sieve into 1000g of 2.0% NaOH solution, heating to 65 ℃, reacting for 30min, rapidly cooling to room temperature, filtering, and washing until the filtrate is neutral. Then, the filter cake was added to 800g of water and slurried, 40g of NH was added₄Cl, heating to 75 ℃, and carrying out exchange treatment for 1h until Na₂The O content is lower than 0.2 weight percent, and a molecular sieve filter cake is obtained after filtering and washing; adding water into 50g (dry basis) of the molecular sieve to prepare molecular sieve slurry with the solid content of 10 weight percent, adding 3g of oxalic acid while stirring, and slowly adding 72g of fluosilicic acid (the mass fraction is 3 percent) for 30 min; heating to 65 ℃, stirring for 1h at constant temperature, filtering and washing until the filtrate is neutral; adding water into the filter cake, pulping to obtain molecular sieve slurry with solid content of 40 wt%, adding 6.3gH₃PO₄(concentration 85% by weight) and 2.5gCu (NO)₃)₂·3H₂And O, uniformly mixing, soaking, drying and roasting at 550 ℃ for 2 hours. Molecular sieve DA5 was obtained, and the physicochemical properties are shown in Table 1.

Comparative example 6

Crystallizing ZSM-5 molecular sieve (produced by catalyst Qilu division, amine-free synthesis, n (SiO)₂)/n(Al₂O₃) 27) the mother liquor was filtered off and washed with water to Na₂The content of O is lower than 3.0 weight percent, and a filter cake is obtained by filtration; adding 100g (dry basis) of the molecular sieve into 1000g of 2.0% NaOH solution, heating to 65 ℃, reacting for 30min, rapidly cooling to room temperature, filtering, and washing until the filtrate is neutral. Then, the filter cake was added to 800g of water and slurried, 40g of NH was added₄Cl, heating to 75 ℃, and carrying out exchange treatment for 1h until Na₂The O content is lower than 0.2 weight percent, and a molecular sieve filter cake is obtained after filtering and washing; 50g (dry basis) of the molecular sieve is taken and added with water to prepare molecular sieve slurry with the solid content of 10 weight percent, and 42g of hydrochloric acid (the mass fraction is 10 percent) and 78g of fluosilicic acid (the mass fraction is 3 percent) are mixed in parallel under stirringAdding for 30 min; heating to 65 ℃, stirring for 1h at constant temperature, filtering and washing until the filtrate is neutral; adding water into the filter cake, pulping to obtain molecular sieve slurry with solid content of 40 wt%, adding 6.3gH₃PO₄(concentration 85% by weight) and 2.5gCu (NO)₃)₂·3H₂And O, uniformly mixing, soaking, drying and roasting at 550 ℃ for 2 hours. Molecular sieve DA6 was obtained, and the physicochemical properties are shown in Table 1.

Comparative example 7

The crystallized ZSM-5 molecular sieve (produced by catalyst Jianchangdian company, synthesized by amine method, n (SiO)₂)/n(Al₂O₃) 50) the mother liquor was filtered off and washed with water to Na₂The content of O is lower than 3.0 weight percent, the mixture is filtered, dried and roasted in the air at 550 ℃ for 2 hours to burn off the template agent; adding 100g (dry basis) of the molecular sieve into 3000g of NaOH aqueous solution (the solution concentration is 0.8%), stirring, heating to 80 ℃, reacting for 30min, cooling to room temperature, filtering, and leaching to obtain a filter cake; adding nitric acid aqueous solution into the obtained molecular sieve filter cake for washing, and specifically, adding water into 50g (dry basis) of the molecular sieve to prepare molecular sieve slurry with the solid content of 10 weight percent, and adding 550g of 2.3 percent nitric acid under stirring; heating to 65 ℃, stirring for 1h at constant temperature, filtering and washing until the filtrate is neutral; adding 1500g of water into the filter cake, pulping, adding 80g of NH₄Heating Cl to 65 ℃, exchanging and washing for 40min, filtering, and leaching until the filtrate is neutral; adding water into the filter cake, pulping to obtain molecular sieve slurry with solid content of 40 wt%, adding 6.3gH₃PO₄(concentration 85% by weight) and 2.5gCu (NO)₃)₂·3H₂And O, uniformly mixing, soaking, drying and roasting at 550 ℃ for 2 hours. Molecular sieve DA7 was obtained, and the physicochemical properties are shown in Table 1.

Comparative example 8

Crystallizing ZSM-5 molecular sieve (produced by catalyst Qilu division, amine-free synthesis, n (SiO)₂)/n(Al₂O₃) 27) the mother liquor was filtered off and washed with water to Na₂The content of O is lower than 3.0 weight percent, and a filter cake is obtained by filtration; taking 100g (dry basis) of the molecular sieve, adding water to prepare molecular sieve slurry with the solid content of 10 weight percent, adding 3g of ethylene diamine tetraacetic acid into the mixture while stirring, and then adding 400g of fluosilicic acid (mass fraction)3%) for 30min, and finally adding 140g of hydrochloric acid (mass fraction: 10%); heating to 85 ℃, stirring for 6 hours at constant temperature, filtering and washing until the filtrate is neutral; adding 1000g of 2.4% NaOH solution, heating to 60 ℃, reacting for 45min, rapidly cooling to room temperature, filtering, and washing until the filtrate is neutral. Then NH₄Cl solution exchange washing to Na₂The content of O is lower than 0.1 weight percent, and a molecular sieve filter cake is obtained by filtering; adding water into 50g (dry basis) of the molecular sieve filter cake, pulping to obtain molecular sieve slurry with the solid content of 40 weight percent, and adding 6.3g of H₃PO₄(concentration 85% by weight) and 2.5gCu (NO)₃)₂·3H₂And O, uniformly mixing, soaking, drying and roasting at 550 ℃ for 2 hours. Molecular sieve DA8 was obtained, and the physicochemical properties are shown in Table 1.

Comparative example 9

The crystallized ZSM-5 molecular sieve (produced by catalyst Jianchangdian company, synthesized by amine method, n (SiO)₂)/n(Al₂O₃) 37) filtering off the mother liquor and then adding NH₄Cl exchange washing to Na₂The content of O is lower than 0.2 weight percent, the mixture is dried and roasted for 2 hours in the air at 550 ℃ to burn off the template agent; adding water into 100g (dry basis) of the molecular sieve, pulping to obtain molecular sieve pulp with the solid content of 40 weight percent, and adding 12.6g of H₃PO₄(concentration 85%) 5.0gCu (NO)₃)₂·3H₂O, dipping and drying; and roasting the obtained sample at 550 ℃ for 2 hours to obtain the molecular sieve DA 9. Physicochemical properties are shown in Table 1.

Example 2

Crystallizing ZSM-5 molecular sieve (produced by catalyst Qilu division, amine-free synthesis, n (SiO)₂)/n(Al₂O₃) 27) the mother liquor was filtered off and washed with water to Na₂The content of O is lower than 3.0 weight percent, and a filter cake is obtained by filtration; adding 100g (dry basis) of the molecular sieve into 1500g of 2.3% NaOH solution, heating to 60 ℃, reacting for 45min, rapidly cooling to room temperature, filtering, and washing until the filtrate is neutral. Then, the filter cake was added to 800g of water and slurried, 40g of NH was added₄Cl, heating to 75 ℃, and carrying out exchange treatment for 1h until Na₂The O content is lower than 0.2 weight percent, and a molecular sieve filter cake is obtained after filtering and washing; mixing the above molecular sieve 50g (dry basis) with waterPreparing molecular sieve slurry with the solid content of 10 weight percent, adding 4g of citric acid while stirring, then adding 10g of sulfuric acid (the mass fraction is 10%) and 45g of fluosilicic acid (the mass fraction is 3%) in a concurrent flow manner, and adding for 30 min; heating to 45 ℃, stirring for 1h at constant temperature, filtering and washing until the filtrate is neutral; adding water into the filter cake, pulping to obtain molecular sieve slurry with solid content of 40 wt%, adding 6.3gH₃PO₄(concentration 85% by weight) and 4.0g Fe (NO)₃)₃·9H₂And O, uniformly mixing, soaking, drying and roasting at 550 ℃ for 2 hours. The molecular sieve B is obtained, and the physicochemical properties are shown in Table 1.

Example 3

Crystallizing ZSM-5 molecular sieve (produced by catalyst Qilu division, amine-free synthesis, n (SiO)₂)/n(Al₂O₃) 27) the mother liquor was filtered off and washed with water to Na₂The content of O is lower than 3.0 weight percent, and a filter cake is obtained by filtration; adding 100g (dry basis) of the molecular sieve into 1200g of 2.2% NaOH solution, heating to 55 ℃, reacting for 60min, rapidly cooling to room temperature, filtering, and washing until the filtrate is neutral. Then, the filter cake was added to 1000g of water and slurried, 50g of NH was added₄Cl, heating to 75 ℃, and carrying out exchange treatment for 1h until Na₂The O content is lower than 0.2 weight percent, and a molecular sieve filter cake is obtained after filtering and washing; taking 50g (dry basis) of the molecular sieve, adding water to prepare molecular sieve slurry with the solid content of 10 weight percent, adding 2g of ethylene diamine tetraacetic acid while stirring, then adding 140g of fluosilicic acid (the mass fraction is 3%) in a flowing manner for 30min, and finally adding 60g of hydrochloric acid (the mass fraction is 10%); heating to 85 ℃, stirring for 6 hours at constant temperature, filtering and washing until the filtrate is neutral; adding water into the filter cake, pulping to obtain molecular sieve slurry with solid content of 40 wt%, adding 6.3gH₃PO₄(concentration 85% by weight) and 3.8g Fe (NO)₃)₃·9H₂And O, uniformly mixing, soaking, drying and roasting at 550 ℃ for 2 hours. The molecular sieve C was obtained, and the physicochemical properties are shown in Table 1.

Comparative example 10

Crystallizing ZSM-5 molecular sieve (produced by catalyst Qilu division, amine-free synthesis, n (SiO)₂)/n(Al₂O₃) 27) the mother liquor was filtered off and washed with water to Na₂The content of O is lower than 3.0 weight percent, and a filter cake is obtained by filtration; getAdding 100g (dry basis) of the molecular sieve into 1200g of 2.2% NaOH solution, heating to 55 ℃, reacting for 60min, rapidly cooling to room temperature, filtering, and washing until the filtrate is neutral. Then, the filter cake was added to 1000g of water and slurried, 50g of NH was added₄Cl, heating to 75 ℃, and carrying out exchange treatment for 1h until Na₂The O content is lower than 0.2 weight percent, and a molecular sieve filter cake is obtained after filtering and washing; taking 50g (dry basis) of the molecular sieve, adding water to prepare molecular sieve slurry with the solid content of 10 weight percent, adding 2g of ethylene diamine tetraacetic acid while stirring, then adding 140g of fluosilicic acid (the mass fraction is 3%) in a flowing manner for 30min, and finally adding 60g of hydrochloric acid (the mass fraction is 10%); heating to 85 ℃, stirring for 6 hours at constant temperature, filtering and washing until the filtrate is neutral; adding water into the filter cake, pulping to obtain molecular sieve slurry with solid content of 40 wt%, adding 5.9gH₃PO₄(concentration: 85 wt.%), mixing, immersing, baking, and calcining at 550 deg.C for 2 hr. The molecular sieve DC1 was obtained, and the physicochemical properties are shown in Table 1.

As can be seen from the data in Table 1, for the ZSM-5 molecular sieve subjected to alkali treatment and desiliconization, Al in the molecular sieve cannot be effectively removed by adopting single organic acid oxalic acid for dealuminization (DA1), or adopting single inorganic acid hydrochloric acid for dealuminization (DA2) or adopting two acids of organic acid oxalic acid and inorganic acid hydrochloric acid for compounding (DA4), the molecular sieve still has aluminum-rich surface, and a good dealuminization effect can be obtained only after fluosilicic acid is used, so that the aluminum distribution of the molecular sieve is improved. When fluosilicic acid alone is used for dealumination (DA3), the aluminum distribution of the molecular sieve can be improved, but the mesopores are relatively less, the proportion of strong acid in the total acid is lower, and the proportion of B acid/L acid is lower. The fluosilicic acid and organic acid composite oxalic acid dealumination (DA5) can not obtain higher mesopore proportion and better acidity distribution. Fluosilicic acid complex mineral acid salt dealumination (DA6) showed an increase in mesopore volume, but neither the proportion of strong acid in the total acid nor the B acid/L acid ratio was as high as the molecular sieve provided by the present disclosure. The ZSM-5 molecular sieve with high silicon-aluminum ratio is treated by alkali and then treated by inorganic acid nitric acid (DA7), although a higher mesopore proportion can be obtained, the pore volume of the molecular sieve with the pore diameter of 2nm to 20nm accounts for the volume of the total mesopores, the pore diameter of the molecular sieve is enlarged, meanwhile, the Al distribution of the molecular sieve is still poor, strong acid is less, the ratio of B acid to L acid is low, the stability of the molecular sieve is poor, and the reaction activity is low. By adopting the technical route of firstly dealuminizing and then desiliconizing, the silica-alumina ratio of the ZSM-5 molecular sieve is improved by using composite acid containing fluosilicic acid, and then the molecular sieve (DA8) is obtained by desiliconizing treatment, the crystallinity is low, the mesoporous proportion is low, the pore volume of the molecular sieve with the medium pore diameter of 2nm to 20nm accounts for the total mesopore volume, and the Al on the outer surface of the molecular sieve is relatively more. According to the method, after the molecular sieve is subjected to desiliconization treatment, a composite acid system is used, and dealuminization treatment is performed under the synergistic effect of three acids, so that the aluminum distribution and the acid distribution can be improved on the premise of ensuring the integrity of a molecular sieve crystal structure and a mesoporous pore structure. The molecular sieve is introduced with metal, so that the dehydrogenation function is increased, and the yield and the selectivity of propylene are further improved.

Examples 4-7 provide a phosphoaluminate inorganic binder for use in the present disclosure.

Example 4

This example prepared a phosphoaluminate inorganic binder as described in the present disclosure.

1.91 kg of pseudoboehmite (containing Al)₂O₃1.19 Kg), 0.56 Kg kaolin (0.50 Kg on a dry basis) and 3.27 Kg decationized water, beating for 30 minutes, adding 5.37 Kg concentrated phosphoric acid (85% by mass) into the slurry under stirring, wherein the adding speed of the phosphoric acid is 0.04Kg phosphoric acid/min/Kg alumina source, heating to 70 ℃, and then reacting for 45 minutes at the temperature to obtain the phosphorus-aluminum inorganic binder. The material ratio is shown in Table 2, and the Binder Binder1 is obtained.

Examples 5 to 7

The phosphor-aluminum inorganic Binder was prepared by the method of example 4, and the material ratio is shown in table 2, to obtain Binder 2-4.

Examples 8-13 provide catalytic cracking aids of the present disclosure, and comparative examples 11-20 provide comparative catalytic cracking aids.

Example 8

Adding decationized water and aluminum sol into molecular sieve A, kaolin and pseudo-boehmite, pulping for 120 minutes to obtain slurry with the solid content of 30 weight percent, adding hydrochloric acid to adjust the pH value of the slurry to be 3.0, continuously pulping for 45 minutes, adding the phosphorus-aluminum inorganic binder prepared in example 4, stirring for 30 minutesThen, the obtained slurry is spray-dried to obtain microspheres, and the microspheres are roasted at 500 ℃ for 1 hour to obtain ZJ₁The compounding ratio is shown in Table 3.

Example 9

Adding decationized water and aluminum sol into molecular sieve B, kaolin and pseudo-boehmite, pulping for 120 minutes to obtain slurry with the solid content of 30 weight percent, adding hydrochloric acid to adjust the pH value of the slurry to be 3.0, continuously pulping for 45 minutes, adding the phosphorus-aluminum inorganic binder prepared in example 4, stirring for 30 minutes, spray-drying the obtained slurry to obtain microspheres, roasting the microspheres at 500 ℃ for 1 hour to obtain ZJ₂The compounding ratio is shown in Table 3.

Example 10

Adding decationized water and aluminum sol into molecular sieve C, kaolin and pseudo-boehmite, pulping for 120 minutes to obtain slurry with the solid content of 30 weight percent, adding hydrochloric acid to adjust the pH value of the slurry to be 3.0, continuously pulping for 45 minutes, adding the phosphorus-aluminum inorganic binder prepared in the embodiment 4, stirring for 30 minutes, spray-drying the obtained slurry to obtain microspheres, roasting the microspheres at 500 ℃ for 1 hour to obtain ZJ₃The compounding ratio is shown in Table 3.

Example 11

Adding decationized water and aluminum sol into molecular sieve A, kaolin and pseudo-boehmite, pulping for 120 minutes to obtain slurry with the solid content of 30 weight percent, adding hydrochloric acid to adjust the pH value of the slurry to be 3.0, continuously pulping for 45 minutes, adding the phosphorus-aluminum inorganic binder prepared in example 5, stirring for 30 minutes, spray-drying the obtained slurry to obtain microspheres, roasting the microspheres at 500 ℃ for 1 hour to obtain ZJ₄The compounding ratio is shown in Table 3.

Example 12

Adding decationized water and silica sol into molecular sieve A, kaolin and pseudo-boehmite, pulping for 120 minutes to obtain slurry with the solid content of 30 weight percent, adding hydrochloric acid to adjust the pH value of the slurry to be 3.0, continuing pulping for 45 minutes, adding the phosphorus-aluminum inorganic binder prepared in example 6, stirring for 30 minutes, spray-drying the obtained slurry to obtain microspheres, roasting the microspheres for 1 hour at 500 ℃,to obtain ZJ₅The compounding ratio is shown in Table 3.

Example 13

Adding decationized water and alumina sol into molecular sieve A, kaolin and pseudo-boehmite, pulping for 120 minutes to obtain slurry with the solid content of 30 weight percent, adding hydrochloric acid to adjust the pH value of the slurry to be 3.0, continuing pulping for 45 minutes, adding the phosphorus-aluminum inorganic binder prepared in example 7, stirring for 30 minutes, and performing spray drying on the obtained slurry to obtain the microspheres. Adding the obtained microsphere product into 7.5 wt% diammonium hydrogen phosphate aqueous solution, heating to 60 deg.C under stirring, reacting at the temperature for 20 min, vacuum filtering the slurry, drying, and calcining at 500 deg.C for 2 hr to obtain auxiliary agent ZJ₆The compounding ratio of the auxiliary is shown in Table 3.

Comparative examples 11 to 20

A catalytic cracking promoter was prepared as described in example 8, except that molecular sieves DA1, DA2, DA3, DA4, DA5, DA6, DA7, DA8, DA9 and DC1 were used in place of A, to prepare a promoter DZJ₁-DZJ₁₀The compounding ratio is shown in Table 4.

Blank test example, examples 14-19 use a small fixed fluidized bed reactor to incorporate 100% of the balancing agent and the adjuvant ZJ prepared in the examples of the present disclosure₁-ZJ₆The reaction performance evaluation was conducted to demonstrate the catalytic cracking reaction effect of the catalytic cracking aids provided by the present disclosure.

Blank test example, examples 14 to 19

Respectively mixing auxiliary agents ZJ₁-ZJ₆The aging treatment was carried out at 800 ℃ under a 100% steam atmosphere for 17 hours. Taking the aged ZJ₁-ZJ₆Separately mixed with an industrial FCC equilibrium catalyst (commercial grade DVR-3 FCC equilibrium catalyst, micro-reverse activity 63). 100 percent of balancing agent and catalyst mixture is loaded into a small-sized fixed fluidized bed reactor, and the raw oil shown in the table 5 is subjected to catalytic cracking under the following reaction conditions: the reaction temperature is 500 ℃, and the weight hourly space velocity is 8h^-1And the weight ratio of the solvent to the oil is 6. The weight composition of the respective catalyst mixtures and the reaction results are given in table 6.

Comparative examples 21 to 30 useSmall-sized fixed fluidized bed reaction device for adding balancing agent into auxiliary DZJ prepared in comparative example of the disclosure₁-DZJ₁₀Performance evaluations were conducted to illustrate the case where the comparative aid was used.

Comparative examples 21 to 30

The same feed oil was catalytically cracked in the same manner as in example 14, except that the catalysts used were DZJ each which was an aid obtained by aging in the same manner as in example 14₁-DZJ₁₀Mixtures with commercial FCC equilibrium catalysts. The weight composition of the individual catalyst mixtures and the reaction results are given in Table 7.

As can be seen from tables 6 and 7, the catalytic promoter provided by the present disclosure can effectively increase the yields of catalytically cracked propylene and liquefied gas, while significantly increasing the concentration of propylene in the catalytically cracked liquefied gas, compared to the comparative promoter.

TABLE 1

Molecular sieves	A	DA1	DA2	DA3	DA4	DA5	DA6	DA7	DA8	DA9	B	C	DC1
														Degree of crystallization/%)	87	80	78	83	83	83	85	77	78	90	90	87	87
n(SiO₂)/n(Al₂O₃)	35	24	23	42	24	39	43	29	29	37	23	50	50
														P₂O₅Content/%	7.5	7.2	7.5	7.5	7.5	7.5	7.5	7.5	7.5	7.5	7.5	7.0	7.0
Content of supported metal oxide/%)	1.5	1.5	1.5	1.5	1.5	1.5	1.5	1.5	1.5	1.5	1.5	1.4	0
														S_BET/(m²/g)	415	370	361	379	371	390	384	371	354	360	448	430	437
(V_Mesopores/V_{General hole})/％	58	41	39	49	45	50	55	72	45	11.4	55	59	60
														(V_2nm-20nm/V_Mesopores)/％	90	80	80	86	77	82	82	63	74	77	95	90	90
(amount of strong acid/total acid)/%	60	40	39	51	37	55	51	40	43	48	58	63	65
														Acid amount of B acid/acid amount of L acid	15	4.9	5.0	10	5.0	13.1	11.2	4.7	4.6	6.1	17.2	19.1	20.9
D (Al distribution)	0.75	1.1	1.1	0.95	1.1	0.87	0.91	1.2	1.1	1.0	0.80	0.72	0.72

TABLE 2

TABLE 3

TABLE 4

TABLE 5

Density, g/cm³(20℃)	0.8994
		Viscosity (100C), mm²/s	5.63
Freezing point, deg.C	34
		Carbon residue, by weight%	0.25
Element content, wt%
		C	87.08
H	12.57
		S	0.23
N	0.12
		Metal content,. mu.g/g
Ca	0.4
		Fe	0.2
Na	0.6
		Ni	<0.1
V	<0.1
		Distillation range, deg.C
Initial boiling point	265
		10％	333
50％	426
		70％	470
86.9％	564

TABLE 6

TABLE 7

Claims

1. A catalytic cracking assistant for increasing the yield of propylene, which comprises 10-75 wt% of phosphorus-containing and metal-loaded MFI structure molecular sieve based on the dry weight of the assistant, 3-40 wt% of phosphorus-aluminum inorganic binder based on the dry weight, 1-30 wt% of other inorganic binders based on oxides and 0-60 wt% of second clay based on the dry weight; wherein the content of the first and second substances,

the phosphor-aluminum inorganic binder is phosphorAluminum glue and/or a first clay-containing aluminophosphate inorganic binder, wherein the first clay-containing aluminophosphate inorganic binder comprises Al based on the dry weight of the first clay-containing aluminophosphate inorganic binder₂O₃15-40% by weight, calculated as P, of an aluminium component₂O₅45-80 wt% of phosphorus component and more than 0 and not more than 40 wt% of first clay calculated on dry basis weight, and the P/Al weight ratio is 1.0-6.0, pH value is 1-3.5, solid content is 15-60 wt%;

n (SiO) of the molecular sieve₂)/n(Al₂O₃) Greater than 18 and less than 70; with P₂O₅The phosphorus content of the molecular sieve is 1-15 wt% based on the dry weight of the molecular sieve; the content of the loaded metal in the molecular sieve is 0.1-5 wt% based on the oxide of the loaded metal and the dry basis weight of the molecular sieve; the Al distribution parameter D of the molecular sieve meets the following requirements: d is more than or equal to 0.6 and less than or equal to 0.85, wherein D = Al (S)/Al (C), Al (S) represents the aluminum content of a region which is arbitrarily more than 100 square nanometers in the distance H from the edge of the crystal face of the molecular sieve crystal grain to the inside measured by a TEM-EDS method, Al (C) represents the aluminum content of a region which is arbitrarily more than 100 square nanometers in the distance H from the geometric center of the crystal face of the molecular sieve crystal grain to the outside measured by a TEM-EDS method, wherein H is 10% of the distance from a certain point of the edge of the crystal face to the geometric center of the crystal face; the proportion of the mesopore volume of the molecular sieve in the total pore volume is 40-70%, and the proportion of the mesopore volume with the pore diameter of 2-20 nm in the total mesopore volume is more than 85%; the ratio of the strong acid amount of the molecular sieve to the total acid amount is 45-75%, and the ratio of the acid amount of the B acid to the acid amount of the L acid is 8-30.

2. The adjuvant of claim 1, wherein n (SiO) of the molecular sieve₂)/n(Al₂O₃) Greater than 21 and less than 60; with P₂O₅The phosphorus content of the molecular sieve is 3-12 wt% based on the dry weight of the molecular sieve; the content of the loaded metal in the molecular sieve is 0.5-3 wt% based on the oxide of the loaded metal and the dry basis weight of the molecular sieve; the Al distribution parameter D of the molecular sieve meets the following requirements: d is more than or equal to 0.65 and less than or equal to 0.82; said divisionThe proportion of the volume of the mesopores of the sub-sieve to the total pore volume is 45-65%, and the proportion of the volume of the mesopores with the pore diameter of 2-20 nm to the total mesopore volume is more than 90%; the ratio of the strong acid amount of the molecular sieve to the total acid amount is 55-70%, and the ratio of the acid amount of the B acid to the acid amount of the L acid is 10-25.

3. The adjuvant according to claim 1, wherein the supporting metal is at least one selected from iron, cobalt, nickel, copper, manganese, tin and bismuth.

4. The adjuvant according to claim 1, wherein the first clay is at least one selected from kaolin, sepiolite, attapulgite, rectorite, montmorillonite and diatomaceous earth; the second clay is at least one selected from kaolin, metakaolin, diatomite, sepiolite, attapulgite, montmorillonite and rectorite; the other inorganic binder is at least one selected from pseudo-boehmite, alumina sol, silica-alumina sol and water glass.

5. The adjuvant according to any one of claims 1 to 4, wherein the adjuvant further comprises P based on the dry weight of the adjuvant₂O₅Up to 5 wt% of a phosphorus additive.

6. The adjuvant of claim 5 wherein the adjuvant comprises 8-25 wt% of a phosphorus aluminum inorganic binder, 20-60 wt% of a phosphorus and metal loaded MFI structure molecular sieve, 10-45 wt% of a second clay, 5-25 wt% of other inorganic binders, and 0-3 wt% of a phosphorus additive.

7. A preparation method of a catalytic cracking auxiliary agent for increasing the yield of propylene comprises the following steps:

mixing the MFI structure molecular sieve containing phosphorus and loaded metal, the phosphorus-aluminum inorganic binder and other inorganic binders, adding or not adding second clay, pulping, and spray-drying; wherein, a phosphorus additive is introduced or not introduced;

starting from preparations with auxiliariesThe preparation raw materials of the additive comprise 10-75 wt% of MFI structure molecular sieve containing phosphorus and supported metal based on the weight of dry basis, 3-40 wt% of phosphorus-aluminum inorganic binder based on the weight of dry basis, 1-30 wt% of other inorganic binders based on oxides, 0-60 wt% of second clay based on the weight of dry basis, and the additive or the additive does not comprise the additive based on the weight of dry basis₂O₅Up to 5 wt% of a phosphorus additive; wherein the content of the first and second substances,

the phosphorus-aluminum inorganic binder is phosphorus-aluminum glue and/or phosphorus-aluminum inorganic binder containing first clay, and the phosphorus-aluminum inorganic binder containing the first clay comprises Al based on the dry weight of the phosphorus-aluminum inorganic binder containing the first clay₂O₃15-40% by weight, calculated as P, of an aluminium component₂O₅45-80 wt% of phosphorus component and more than 0 and not more than 40 wt% of first clay calculated on dry basis weight, and the P/Al weight ratio is 1.0-6.0, pH value is 1-3.5, solid content is 15-60 wt%;

8. The production method according to claim 7, wherein the step of producing the phosphorus-and metal-containing MFI structure molecular sieve comprises:

a. desiliconizing the sodium type MFI structure molecular sieve in an alkali solution to obtain a desiliconized molecular sieve;

b. performing ammonium exchange on the desiliconized molecular sieve obtained in the step a to obtain an ammonium exchange molecular sieve; wherein the ammonium exchanged molecular sieve has a sodium content of less than 0.2 wt.% based on sodium oxide and based on total dry basis weight of the ammonium exchanged molecular sieve;

c. b, dealuminizing the ammonium exchange molecular sieve obtained in the step b in a composite acid dealuminizing agent solution consisting of fluosilicic acid, organic acid and inorganic acid, and filtering and washing to obtain a dealuminized molecular sieve; the inorganic acid is at least one selected from ethylenediamine tetraacetic acid, oxalic acid, citric acid and sulfosalicylic acid, and the organic acid is at least one selected from hydrochloric acid, sulfuric acid and nitric acid;

d. and c, carrying out phosphorus modification treatment, load metal modification treatment and roasting treatment on the dealuminized molecular sieve obtained in the step c to obtain the MFI structure molecular sieve containing phosphorus and load metal.

9. The preparation method according to claim 8, wherein the preparation of the sodium MFI structure molecular sieve in step a comprises:

filtering and washing MFI structure molecular sieve slurry obtained by amine crystallization to obtain a washed molecular sieve; wherein the sodium content of the water-washed molecular sieve is less than 3.0 wt% based on the total dry basis weight of the water-washed molecular sieve calculated on sodium oxide;

and drying and air roasting the water washed molecular sieve to obtain the sodium type MFI structure molecular sieve.

10. The method according to claim 8, wherein the alkali solution in step a is selected from the group consisting of an aqueous sodium hydroxide solution, an aqueous potassium hydroxide solution and aqueous ammonia.

11. The production method according to claim 8, wherein the conditions of the desiliconization treatment in step a include: the weight ratio of the sodium type MFI structure molecular sieve, alkali in the alkali solution and water in the alkali solution is 1: (0.1-2): (5-20), wherein the desiliconization treatment temperature is between room temperature and 100 ℃, and the time is 0.2-4 hours.

12. The production method according to claim 8, wherein the conditions of the desiliconization treatment in step a include: the weight ratio of the sodium type MFI structure molecular sieve, alkali in the alkali solution and water in the alkali solution is 1: (0.2-1): (5-20).

13. The preparation method according to claim 8, wherein the dealumination treatment conditions in step c include: the weight ratio of the ammonium exchanged molecular sieve, the organic acid, the inorganic acid and the fluorosilicic acid on a dry weight basis is 1: (0.01-0.3): (0.01-0.3): (0.01-0.3); the dealuminization treatment temperature is 25-100 ℃, and the time is 0.5-6 hours.

14. The preparation method according to claim 8, wherein the dealumination treatment conditions in step c include: the weight ratio of the ammonium exchanged molecular sieve, the organic acid, the inorganic acid and the fluorosilicic acid on a dry weight basis is 1: (0.03-0.2): (0.015-0.2): (0.015-0.2).

15. The method of claim 8, wherein the phosphorus modification treatment in step d comprises: at least one phosphorus-containing compound selected from phosphoric acid, ammonium hydrogen phosphate, ammonium dihydrogen phosphate and ammonium phosphate is used to impregnate and/or ion-exchange the molecular sieve.

16. The production method according to claim 8, wherein the supported metal modification treatment comprises: a compound containing at least one supported metal selected from the group consisting of iron, cobalt, nickel, copper, manganese, tin and bismuth is used to support the supported metal on a molecular sieve by an impregnation method.

17. The production method according to claim 8, wherein the conditions of the baking treatment include: the atmosphere of the roasting treatment is air atmosphere or water vapor atmosphere; the roasting temperature is 400-800 ℃, and the roasting time is 0.5-8 hours.

18. The method of claim 7, wherein the first clay-containing aluminophosphate inorganic binder is prepared by a method comprising:

(1) pulping and dispersing an alumina source, first clay and water into slurry with the solid content of 8-45 wt%; the alumina source is aluminum hydroxide and/or aluminum oxide which can be peptized by acid, and Al is relative to more than 0 and not more than 40 parts by weight of first clay calculated by dry weight₂O₃The dosage of the alumina source is 15-40 parts by weight;

(2) adding concentrated phosphoric acid into the slurry obtained in the step (1) according to the weight ratio of P/Al =1-6 under stirring;

(3) and (3) reacting the slurry obtained in the step (2) at the temperature of 50-99 ℃ for 15-90 minutes.