High-strength, large-pore-volume phosphorus-containing binder, its preparation method and application

Abstract

The application discloses a high-strength, large-pore-volume phosphorus-containing binder, characterized in that the binder comprises a glue, a curing agent and a modifier; the glue comprises a phosphorus-containing compound and an aluminum-containing compound; the curing agent comprises a gamma-aluminum oxide precursor, an acid and an alkylammonium salt, and the modifier is a metal chelate; wherein the colloidal solubility index of the gamma-aluminum oxide precursor is less than or equal to 50%; and the modifier is reacted with the glue in a high-shear dispersion emulsifier. The phosphorus-containing binder provided by the application, in combination with a conventional method, can obtain a catalytic cracking catalyst which, on the basis of high molecular sieve content and large pore volume, still has high wear resistance.

Description

Technical Field

[0001] This invention belongs to the field of adhesive technology, specifically relating to a high-strength, macroporous phosphorus-containing adhesive, its preparation method, and its application. Background Technology

[0002] With the increasing deterioration and heavier composition of crude oil and the maturation of heavy oil extraction technologies, the proportion of heavy oil in the world's crude oil supply is constantly increasing. Catalytic cracking, with its significant advantages such as high heavy oil conversion efficiency, good product quality, non-hydrogenation, and low operating pressure, has become the most important process for heavy oil processing. The core of technological advancements in catalytic cracking lies in catalytic cracking catalysts.

[0003] Catalytic cracking catalysts mainly consist of a matrix, active components, and a binder. The binder not only binds the matrix and active components but also provides a certain heat capacity during the catalytic cracking reaction. Furthermore, the binder's performance directly affects the physicochemical properties of the catalyst, such as particle size, attrition index, and pore volume. The catalyst's pores are the sites of catalytic reactions and channels for diffusion and mass transfer; their pore structure directly affects the catalyst's activity and selectivity. The catalyst's attrition index significantly impacts the strength of the catalyst support, easily leading to support fragmentation and a reduction in the quality of the prepared catalyst. Therefore, the binder directly influences the performance of catalytic cracking catalysts.

[0004] For example, Chinese patent document CN201680055564.2 discloses a method for manufacturing a fluidized bed catalytic cracking catalyst additive composition using a novel binder. The steps involve mixing an alumina source with water to form a slurry; adding a certain amount of P2O5 source to the alumina slurry; then stirring the slurry and reacting it under controlled temperature and time conditions to form an aluminum phosphate binder; adding zeolite, a certain amount of silica binder, and a certain amount of clay to the aluminum phosphate binder; and spray drying the slurry to form catalyst additive particles. The catalyst additive composition comprises about 35 wt% to about 65 wt% zeolite; about 0 wt% to about 10 wt% silica; about 15 wt% to about 50 wt% clay; and an aluminum phosphate binder comprising about 2.5 wt% to 5 wt% amorphous or pseudoboehmite alumina and about 7 wt% to 15 wt% phosphoric acid. This literature uses aluminum phosphate binder and introduces silica during catalyst preparation to achieve a binding effect. However, the introduction of silica reduces the activity of the catalyst matrix, and the use of aluminum phosphate binder reduces the pore volume and specific surface area of ​​the catalyst. During application, it reduces the diffusion of large reactant molecules, leading to increased coke yield and decreased selectivity of the cracking reaction. The application of aluminum phosphate binder increases the thermal breakdown rate of the catalyst and reduces its thermal abrasion performance. In practical use, it can cause an increase in the fine powder content of the unit, resulting in problems such as abnormal fluidization, catalyst loss, scale buildup in the flue gas turbine, and increased solids content in the slurry, thus affecting the long-term operation of the catalytic cracking unit.

[0005] Patent documents US5286369, CN102049284B, CN102847547B, CN1957070A, CN101376830A, CN1957070A, and CN1132897C all use conventional aluminum phosphate as a binder, or use aluminum phosphate to partially or completely replace the existing aluminum sol binder. Due to the characteristics of aluminum phosphate binder, such as low specific surface area, small pores, and easy thermal collapse at high temperatures, it often leads to a deterioration in the physicochemical properties and reaction performance of the catalyst.

[0006] The aluminum phosphate sol (or aluminum phosphate solution) used in the prior art is prepared by reacting phosphorus compounds with aluminum sol or silica sol under controlled pH > 3 conditions; or by precipitating a phosphoric acid solution containing aluminum nitrate and magnesium nitrate with ammonium hydroxide solution at pH = 9 conditions; or by precipitating a solution containing phosphoric acid and rare earth ions with an alkaline solution; or by precipitating a solution containing aluminum ions, phosphate, and hydrogen phosphate with an alkaline solution; or by directly adding an ammonium salt of phosphate, ammonium salt of orthophosphate, and ammonium salt of diphosphite, and a phosphorus compound of phosphate to a slurry containing silica, clay, and zeolite; or by directly adding an aluminum phosphate solution with a pH of 0–1 to a slurry containing zeolite. While using the above binders to prepare catalysts can increase the wear resistance of the catalyst to some extent, its wear resistance is still insufficient when the molecular sieve content in the catalyst is high or the catalyst pore volume is large. Although the underlying mechanism is not yet clear, it has been found that when the molecular sieve content in the additive is high or the pore volume of the additive is large, the additive particles undergo varying degrees of breakage when preparing additives using existing phosphate aluminum sol, especially after high-temperature steam aging. It is speculated that because the aforementioned phosphate aluminum sol contains excessive chloride, ammonium, and nitrate ions, these ions may have a stable bond with the binding components, placing these binding components in an inactive state. During the preparation of the additive, it remains in an inactive state. As a result, on the one hand, this stable bond reduces the bonding effect of the binder. On the other hand, during the spray drying process of the additive, especially during the steam aging process, the chloride, ammonium, and nitrate ions that are stably bonded with the binder become unstable and generate gases such as hydrogen chloride, ammonia, nitrogen, and oxygen, respectively. The generation of these gases causes a large number of "bubbles" to form inside the additive particles. When the temperature rises, these bubbles will burst out from inside the additive, causing damage to the shape of the additive particles. In severe cases, it can lead to the rupture of the additive particles, thereby reducing the bonding effect of various binders and greatly reducing the wear resistance of the additive. Summary of the Invention

[0007] To overcome the above-mentioned shortcomings, the present invention provides a high-strength, large-pore-volume phosphorus-containing binder, its preparation method and application. Compared with existing binders such as aluminum phosphate and aluminum sol, the phosphorus-containing binder provided by the present invention, combined with conventional methods, produces a catalytic cracking catalyst with high molecular sieve content and large pore volume, while still exhibiting high wear resistance.

[0008] To achieve the above objectives, the present invention provides the following technical solution:

[0009] A high-strength, macroporous phosphorus-containing adhesive includes an adhesive compound, a curing agent, and a modifier; the adhesive compound includes a phosphorus-containing compound and an aluminum-containing compound; the curing agent includes a γ-alumina precursor, an acid, and an alkylammonium salt; and the modifier is a metal chelate.

[0010] Among them, the colloidal index of the γ-alumina precursor is ≤50%;

[0011] The modifier reacts with the adhesive in a high-shear dispersion emulsifier.

[0012] Optionally, in the high-strength, macroporous phosphorus-containing binder provided by the present invention, the metal chelate is selected from at least one of phosphonic acid metal chelates, aminocarboxylic acid metal chelates, hydroxyaminocarboxylic acid metal chelates, carboxylic acid metal chelates, and carbonyl metal chelates.

[0013] Optionally, in the high-strength, macroporous phosphorus-containing binder provided by the present invention, the metal chelate is a mixture of at least two metal chelates or a multi-metal chelate containing at least two metals. The metal in the metal chelate is at least one of rare earth metal ions, transition metal ions, alkali metal ions, and alkaline earth metal ions. Preferably, the metal in the metal chelate is a transition metal ion and a rare earth metal ion. The ratio of the various metal ions in the metal chelate is not specifically limited and can be adjusted according to the actual situation. The molar ratio of the transition metal ion to the rare earth metal ion in the metal chelate recommended by the present invention is 5 to 15:1.

[0014] Preferably, the rare earth metal ions are selected from light rare earth metal ions, such as lanthanum ions, cerium ions, neodymium ions, samarium ions, etc.; the transition metal ions are selected from copper, silver, nickel, zinc, cobalt, cadmium, etc.

[0015] Optionally, in the high-strength, macroporous phosphorus-containing binder provided by the present invention, the metal chelate may be selected from at least one of the following: lanthanum chelated with hydroxyethyl ethylenediamine triacetic acid, cerium chelated with hydroxyethyl ethylenediamine triacetic acid, copper chelated with ethylenediaminetetraacetic acid, silver chelated with ethylenediaminetetraacetic acid, copper chelate with aminotrimethylphosphonic acid, silver chelate with n-acyl ethylenediamine triacetic acid, zinc chelate with aminotrimethylphosphonic acid, lanthanum chelated with DOTA, yttrium rare earth chelate with β-diketone, cerium rare earth chelate with β-diketone, and copper and lanthanum bimetallic hydroxyethyl ethylenediamine triacetic acid chelate.

[0016] Optionally, in the high-strength, macroporous phosphorus-containing binder provided by the present invention, the molar ratio of the acid to the γ-alumina precursor (calculated as alumina) in the curing agent is 0.1 to 1:1, preferably 0.2 to 0.5:1. There are no restrictions on the type of acid in the curing agent; commonly used inorganic or organic acids in the industry are acceptable; for example, HCl, HNO3, H2SO4, HCOOH, CH3COOH, etc., can all meet the requirements.

[0017] Optionally, in the high-strength, macroporous phosphorus-containing adhesive provided by the present invention, the alkylammonium salt in the curing agent is not specifically limited, and any conventional alkylammonium salt in the industry is acceptable, such as at least one of hexadecyltrimethylammonium bromide (CTAB), hexadecylpyridine chloride (CPC), and dimethyloctadecylammonium chloride.

[0018] The XRD patterns of the γ-alumina precursors with a colloidal index ≤50% showed characteristic peaks at 2θ of 14±1°, 28±1°, 38±1°, and 49±1°, such as boehmite, boehmite, etc.

[0019] Optionally, in the high-strength, large-pore phosphorus-containing adhesive provided by the present invention, the molar ratio of phosphorus in the phosphorus-containing compound to aluminum in the aluminum-containing compound is 1 to 10:1, preferably 2 to 6:1.

[0020] The aluminum-containing compound and the phosphorus-containing compound are not specifically limited, and any conventional compounds used in the industry are acceptable. The aluminum-containing compound includes, but is not limited to, aluminum oxides, aluminum hydroxides, and aluminum-containing organic compounds, such as aluminum oxide, aluminum hydroxide, sodium aluminate monohydrate, aluminum chloride, and aluminum isopropoxide; preferably, aluminum oxides and aluminum hydroxides. The phosphorus-containing compound includes, but is not limited to, phosphorus oxides, phosphorus oxyacids, phosphoric acid, phosphates, or phosphorus-containing organic compounds, such as phosphoric acid, diammonium hydrogen phosphate, phosphorus pentoxide, organophosphonic acid, sodium phosphate, and calcium phosphate. Preferably, phosphorus oxyacids, phosphoric acid, and phosphorus ammonium salts are preferred.

[0021] Optionally, in the high-strength, macroporous phosphorus-containing adhesive provided by the present invention, based on the dry basis weight of the high-strength, macroporous phosphorus-containing adhesive as 100%, the content of the adhesive is 60wt% to 94wt%, preferably 70wt% to 90wt%; the content of the curing agent is 5wt% to 30wt%, preferably 10wt% to 20wt%; and the content of the modifier (calculated as metal oxide) is 1wt% to 10wt%, preferably 2wt% to 5wt%.

[0022] The mass ratio of the γ-alumina precursor to the alkylammonium salt is 9-30:1.

[0023] The present invention also provides a method for preparing the above-mentioned high-strength, macroporous phosphorus-containing binder, comprising the following steps:

[0024] S1: Mix the γ-alumina precursor with an acid (preferably at 30-100°C for 10-120 min), then add an alkylammonium salt solution and react at 30-100°C (preferably for 15-30 min). After the reaction is complete, perform hydrothermal treatment to obtain a curing agent.

[0025] S2: After mixing the curing agent with deionized water, add aluminum-containing compounds and phosphorus-containing compounds, and control the pH of the system to ≤5 (preferably pH ≤3), then add it to a high-shear dispersing emulsifier for reaction. After the reaction is completed, a mixed slurry is obtained.

[0026] S3: Add a modifier to the mixed slurry and react (preferably at a reaction temperature of 60-100°C for 0.1-1 h). After the reaction is complete, a high-strength, macroporous phosphorus-containing binder with a D90 of less than 8 μm is obtained.

[0027] Optionally, in the preparation method of the high-strength, macroporous phosphorus-containing binder provided by the present invention, the hydrothermal treatment temperature in step S1 is 400-1000℃, the water vapor content is 10-80% (volume content), preferably 20%-60%, and the time is 1-10h, preferably 4-6h.

[0028] Optionally, in the preparation method of the high-strength, macroporous phosphorus-containing binder provided by the present invention, when the phosphorus-containing compound added in step S2 is not acidic, an acid can be added to adjust the pH of the system to ≤5 (preferably pH ≤3). The specific type of acid is not limited, and any conventional inorganic or organic acid in the industry can be used, such as hydrochloric acid, nitric acid, phosphonic acid, etc.

[0029] Optionally, in the preparation method of the high-strength, large-pore phosphorus-containing binder provided by the present invention, the reaction temperature in step S2 is not specifically limited, as long as the aluminum-containing compound and the phosphorus-containing compound can react, such as a reaction temperature of 60-100℃.

[0030] The present invention also provides the application of the above-mentioned high-strength, macroporous phosphorus-containing binder or the high-strength, macroporous phosphorus-containing binder prepared by the above-mentioned preparation method in the preparation of catalytic cracking catalysts, catalytic pyrolysis catalysts or additives.

[0031] Compared with the prior art, the beneficial effects of the present invention are as follows:

[0032] Beneficial Effect 1: The high-strength, large-pore-volume phosphorus-containing binder provided by this invention uses a low-solubility-index γ-alumina precursor in the curing agent. This reduces the solubility of the γ-alumina precursor in the acidic medium during preparation, precisely controlling the presence of free metallic aluminum in the catalyst system and preventing excessive reaction with the binder's effective components, thus affecting the binder's bonding performance. The small portion of the soluble γ-alumina precursor can react with phosphorus-containing compounds in the adhesive under specific conditions to form the binder. Furthermore, the low-solubility-index γ-alumina precursor can form numerous mesopores during curing, increasing the pore volume of the cured binder.

[0033] Beneficial Effect 2: The high-strength, large-pore-volume phosphorus-containing binder provided by this invention introduces metal chelates as modifiers to modify the phosphate binder. The transition metal ions, alkali metal ions, and light rare earth metal ions in the chelates modify the aluminum phosphate binder, strengthening the interaction between aluminum phosphate and the curing agent, and improving strength. Experiments show that the modification by composite metal ions can significantly reduce thermal collapse under high-temperature hydrothermal conditions, greatly improving the thermal wear performance of the catalyst. Simultaneously, the introduction of metal chelates into the binder avoids premature hardening of the colloid during catalyst molding and drying, increasing the pore volume of the binder after curing. Numerous experimental results show that the addition of chelates can form micropores and mesopores within the binder during preparation without affecting its bonding performance.

[0034] Beneficial Effect 3: The method for preparing the high-strength, large-pore-volume phosphorus-containing binder provided by this invention involves adding a γ-alumina precursor and subjecting the material to hydrothermal treatment. Under high-critical conditions, the crystal structure of the γ-alumina precursor partially collapses and recrystallizes, further increasing the pore volume and pore size of the γ-alumina precursor, increasing the number of mesopores on the γ-alumina precursor, and simultaneously modifying the surface structure of the γ-alumina precursor, providing a favorable site and environment for the adhesion of metal ions in the subsequent modifier. On the other hand, using the γ-alumina precursor as a curing agent for the aluminum phosphate binder increases both pore volume and bonding strength. Pretreatment of the γ-alumina precursor with an alkylammonium salt before hydrothermal treatment makes the pore expansion of the γ-alumina precursor during hydrothermal treatment more efficient, and the resulting pore size distribution is more concentrated in the mesopore range, eliminating macropores larger than 20 nm. This improves the pore volume of the binder while enhancing its adhesive performance.

[0035] Beneficial Effect 4: The preparation method of the high-strength, large-pore-volume phosphorus-containing binder provided by this invention employs a high-shear emulsification reactor, which can disperse low-colloidal-index γ-alumina precursors into a uniform and viscous emulsion slurry, overcoming the technical problem that low-colloidal-index γ-alumina precursors have poor solubility and cannot form a uniform slurry. Furthermore, the application of the high-shear emulsification reactor solves the problem of insufficient mixing between multi-metal chelates and aluminum phosphate binders, promoting the mutual reaction between the binder and multi-metal chelates, effectively controlling the microenvironment such as supersaturation distribution within the reactor, and enhancing the effect of the binder's modifying components. Detailed Implementation

[0036] The present invention will now be described in detail through embodiments. It should be noted that the following embodiments are only for further illustration of the present invention and should not be construed as limiting the scope of protection of the present invention. Those skilled in the art can make some non-essential improvements and adjustments to the present invention based on the above description.

[0037] For any experimental steps or conditions not specified in the examples and comparative examples, the procedures and conditions described in the literature in this field can be followed. Reagents or instruments whose manufacturers are not specified are all commercially available conventional reagent products.

[0038] The raw materials and equipment involved in this invention are all commercially available and can all meet the requirements for implementing the technical solution of this invention. However, for ease of comparison, the raw materials from the following sources are used in the following embodiments:

[0039] Y-type molecular sieves and alumina sol were sourced from Lanzhou Petrochemical Company;

[0040] Boehmite, boehmite, and boehmite are produced by Shandong Aluminum Plant of China Aluminum Corporation.

[0041] Kaolin is produced by China Kaolin Co., Ltd.

[0042] Oxalic acid, citric acid, phosphorus pentoxide, aluminum hydroxide, phosphoric acid, diammonium hydrogen phosphate, aluminum oxide, aluminum chloride, copper nitrate, lanthanum chloride, ethylenediaminetetraacetic acid chelated copper, hydroxyethylethylenediaminetriacetic acid chelated lanthanum, ethylenediaminetetraacetic acid chelated silver, hydroxyethylethylenediaminetriacetic acid chelated cerium, aminotrimethylphosphonic acid chelated zinc, DOTA chelated lanthanum, β-diketone rare earth cerium, copper and lanthanum bimetallic hydroxyethylethylenediaminetriacetic acid chelate, phosphoric acid, magnesium oxide, zinc oxide, copper oxide, sodium tripolyphosphate, sodium hexametaphosphate, sodium pyrophosphate, calcium polyphosphate, and sodium magnesium ethylenediaminetetraacetate were all analytical grade and produced by Sinopharm Group.

[0043] Example 1

[0044] In this embodiment, the adhesive contains 60 wt% adhesive, 30 wt% curing agent, and 10 wt% metal chelate modifier (calculated as metal oxide), based on a dry basis of 100%. The specific preparation method is as follows:

[0045] S1: Boehmite with a gel solubility index of 50% was mixed with deionized water, and hydrochloric acid was added. The molar ratio of hydrochloric acid to boehmite (calculated as alumina) was 0.1:1. The mixture was reacted at 30°C for 2 hours, and then hexadecyltrimethylammonium bromide (CTAB) solution was added. The mixture was reacted at 30°C for 30 minutes. Then, hydrothermal treatment was carried out at 400°C with a water vapor content of 10% for 10 hours to obtain curing agent particles. The mass ratio of boehmite to CTAB was 27:3.

[0046] S2: Mix the curing agent particles with water, then add aluminum oxide and phosphorus pentoxide (P / Al molar ratio of 1:1), disperse evenly, add an appropriate amount of hydrochloric acid to adjust the pH of the system to 3.0, then heat to 60℃, stir evenly and add to a high shear dispersion emulsifier for reaction, maintain the temperature at 60℃ for 1 hour to obtain a mixed slurry;

[0047] S3: Add ethylenediaminetetraacetic acid chelated copper to the above mixed slurry and react at 60°C for 1 hour to obtain the adhesive colloid.

[0048] Example 2

[0049] In this embodiment, the adhesive, based on a dry basis of 100%, contains 84 wt% adhesive, 15 wt% curing agent, and 1 wt% metal chelate modifier (calculated as metal oxide). The specific preparation method is as follows:

[0050] S1: Boehmite with a gel solubility index of 30% was mixed with deionized water, and oxalic acid was added. The molar ratio of oxalic acid to boehmite (calculated as alumina) was 1:1. The mixture was reacted at 100°C for 10 min, and then hexadecylpyridine chloride (CPC) solution was added. The mixture was reacted at 100°C for 15 min. Then, the mixture was hydrothermally treated at 1000°C with a water vapor content of 80% for 1 h to obtain curing agent particles. The mass ratio of boehmite to CTAB was 14.5:0.5.

[0051] S2: Mix the curing agent particles with water, then add aluminum hydroxide and phosphoric acid (P / Al molar ratio of 10:1), disperse evenly, at which point the pH of the system is 2.0, then heat to 100℃, stir evenly, and then add to a high shear dispersion emulsifier for reaction, maintaining the temperature at 100℃ for 0.1h to obtain a mixed slurry;

[0052] S3: Add hydroxyethyl ethylenediamine triacetic acid to the above mixed slurry to chelate lanthanum, and react at 100°C for 30 min.

[0053] Example 3

[0054] In this embodiment, the adhesive, based on a dry basis of 100%, contains 70 wt% adhesive, 28 wt% curing agent, and 2 wt% metal chelate modifier (calculated as metal oxide). The specific preparation method is as follows:

[0055] S1: Boehmite with a peptizability index of 20% was mixed with deionized water, and nitric acid was added. The molar ratio of nitric acid to boehmite (calculated as alumina) was 0.2:1. The mixture was reacted at 80°C for 30 min, and then a dimethyloctadecyl ammonium chloride solution was added. The mixture was reacted at 80°C for 15 min. Then, the mixture was hydrothermally treated at 800°C with a water vapor content of 20% for 6 h to obtain curing agent particles. The mass ratio of boehmite to dimethyloctadecyl ammonium chloride was 26:2.

[0056] S2: Mix the curing agent particles with water, then add aluminum isopropoxide and ammonium dihydrogen phosphate (P / Al molar ratio of 2:1), disperse evenly, add hydrochloric acid to adjust the pH of the system to 1.0, then heat to 80℃, stir evenly, and then add to a high shear dispersion emulsifier for reaction. Maintain the temperature at 80℃ for 0.5h to obtain a mixed slurry.

[0057] S3: Add ethylenediaminetetraacetic acid magnesium chelate (EDTA-Mg) to the above mixed slurry and react at 100℃ for 10 min to obtain the binder colloid.

[0058] Example 4

[0059] In this embodiment, the adhesive, based on a dry basis of 100%, contains 85 wt% adhesive, 10 wt% curing agent, and 5 wt% metal chelate modifier (calculated as metal oxide). The specific preparation method is as follows:

[0060] S1: Boehmite with a gel solubility index of 20% was mixed with deionized water, citric acid was added, and the molar ratio of citric acid to boehmite (calculated as alumina) was 0.5:1. The mixture was reacted at 60°C for 1 hour, followed by the addition of dimethyloctadecyl ammonium chloride solution, and the reaction was carried out at 30°C for 30 minutes. Then, the mixture was calcined at 400°C with a water vapor content of 60% for 4 hours to obtain curing agent particles. The mass ratio of boehmite to dimethyloctadecyl ammonium chloride was 9:1.

[0061] S2: Mix the curing agent particles with water, then add aluminum chloride and ammonium dihydrogen phosphate (P / Al molar ratio of 6:1), disperse evenly, add citric acid to adjust the pH of the system to 1.0, then heat to 60℃, stir evenly and add to a high shear dispersion emulsifier for reaction, maintain the temperature at 60℃ for 1 hour to obtain a mixed slurry;

[0062] S3: Add ethylenediaminetetraacetic acid to the above mixed slurry to chelate silver and β-diketone rare earth cerium (iv), with a silver to cerium molar ratio of 15:1; react at 60℃ for 15 min to obtain the binder colloid.

[0063] Example 5

[0064] In this embodiment, the adhesive, based on a dry basis of 100%, contains 77 wt% adhesive, 20 wt% curing agent, and 3 wt% metal chelate modifier (calculated as metal oxide). The specific preparation method is as follows:

[0065] S1: Boehmite with a gel solubility index of 20% was mixed with deionized water, and hydrochloric acid was added. The molar ratio of hydrochloric acid to boehmite (calculated as alumina) was 0.3:1. The mixture was reacted at 70°C for 1 hour. A mixed solution of dimethyl octadecyl ammonium chloride and 0.5% hexadecyltrimethylammonium bromide (CTAB) was added, and the mixture was reacted at 70°C for 30 minutes. Then, the mixture was hydrothermally treated at 700°C with a water vapor content of 50% for 5 hours to obtain curing agent particles. The mass ratio of boehmite, dimethyl octadecyl ammonium chloride, and CTAB was 18.5:1:0.5.

[0066] S2: Mix the curing agent particles with water, then add strong alumina and phosphorus pentoxide (P / Al molar ratio of 4:1), disperse evenly, add citric acid, at which point the pH of the system is 2.0, then heat to 80℃, stir evenly, and then add to a high shear dispersion emulsifier for reaction, maintaining the temperature at 80℃ for 0.5h to obtain a mixed slurry;

[0067] S3: Add copper and lanthanum bimetallic hydroxyethyl ethylenediamine triacetic acid chelate (copper to lanthanum molar ratio of 10:1, react at 60℃ for 15 min to obtain the binder colloid.) to the above mixed slurry.

[0068] Example 6

[0069] In this embodiment, the adhesive, based on a dry basis of 100%, contains 94 wt% adhesive, 5 wt% curing agent, and 1 wt% modifier. The specific preparation method is as follows:

[0070] S1: Boehmite with a gel solubility index of 50% was mixed with deionized water, and hydrochloric acid was added. The molar ratio of hydrochloric acid to boehmite (calculated as alumina) was 0.3:1. The mixture was reacted at 70°C for 1 hour, and then dimethyloctadecyl ammonium chloride solution was added. The mixture was reacted at 80°C for 30 minutes. Then, the mixture was hydrothermally treated at 700°C with a water vapor content of 50% for 5 hours to obtain curing agent particles. The mass ratio of boehmite to dimethyloctadecyl ammonium chloride was 4.5:0.5.

[0071] S2: Mix the curing agent particles with water, then add strong alumina and phosphorus pentoxide (P / Al molar ratio of 4:1), disperse evenly, add citric acid, at which point the pH of the system is 2.0, then heat to 80℃, stir evenly, and then add to a high shear dispersion emulsifier for reaction, maintaining the temperature at 80℃ for 0.5h to obtain a mixed slurry;

[0072] S3: Add copper and lanthanum bimetallic hydroxyethyl ethylenediamine triacetic acid chelate to the above mixed slurry, with a copper to lanthanum molar ratio of 10:1, and react at 60°C for 15 min to obtain the binder colloid.

[0073] Comparative Example 1

[0074] Aluminum sol and boehmite were used as binders. The mass ratio of aluminum sol to boehmite (based on alumina) was 1:2, and the gel solubility index of boehmite was 99%. Boehmite was mixed with 25 wt% hydrochloric acid and gelled at 60°C for 30 min, then mixed with the aluminum sol to obtain the binder. The mass ratio of boehmite (based on alumina) to hydrochloric acid was 1:0.2.

[0075] Comparative Example 2

[0076] Pseudoboehmite alumina is mixed with water to form a slurry, and then phosphoric acid is added to the slurry. The mixture is reacted at 45°C for 3 hours to form aluminum phosphate binder, wherein the mass ratio of pseudoboehmite alumina to phosphoric acid is 4:10.

[0077] Comparative Example 3

[0078] This comparative example is similar to Example 5, except that it does not include a curing agent.

[0079] In this comparative example, based on the dry weight of the adhesive (100%), the adhesive content was 97 wt% and the metal oxide modifier (calculated as metal oxide) content was 3 wt%. The specific preparation method is as follows:

[0080] S1: After dispersing strong alumina and phosphorus pentoxide (P / Al molar ratio of 4:1) evenly, add citric acid to adjust the pH of the system to 2.0, then heat to 80℃, stir evenly and add to a high shear dispersion emulsifier for reaction, maintain the temperature at 80℃ for 0.5h to obtain a mixed slurry;

[0081] S2: Add copper and lanthanum bimetallic hydroxyethyl ethylenediamine triacetic acid chelate (copper to lanthanum molar ratio of 10:1) to the above mixed slurry and react at 60°C for 15 min to obtain the binder colloid.

[0082] Comparative Example 4

[0083] This comparative example is similar to Example 5, except that the dimethyloctadecyl ammonium chloride and CTAB in the curing agent of Example 5 are replaced with an equal mass of ammonium chloride.

[0084] The adhesive provided in this comparative example, based on a dry basis of 100%, contains 77 wt% adhesive, 20 wt% curing agent, and 3 wt% ammonium chloride. The specific preparation method is as follows:

[0085] S1: Boehmite with a gel solubility index of 20% was mixed with deionized water, hydrochloric acid was added, and the molar ratio of hydrochloric acid to boehmite (calculated as alumina) was 0.3:1. The mixture was reacted at 70°C for 1 hour, then ammonium chloride was added, and the mixture was reacted at 70°C for 30 minutes. Then, the mixture was hydrothermally treated at 700°C with a water vapor content of 50% for 5 hours to obtain curing agent particles. The mass ratio of boehmite to ammonium chloride was 18.5:1.5.

[0086] S2: Mix the curing agent particles with water, then add strong alumina and phosphorus pentoxide (P / Al molar ratio of 4:1), disperse evenly, add citric acid, at which point the pH of the system is 2.0, then heat to 80℃, stir evenly, and then add to a high shear dispersion emulsifier for reaction, maintaining the temperature at 80℃ for 0.5h to obtain a mixed slurry;

[0087] S3: Add copper and lanthanum bimetallic hydroxyethyl ethylenediamine triacetic acid chelate (copper to lanthanum molar ratio of 10:1) to the above mixed slurry and react at 60℃ for 15 min to obtain an adhesive colloid with D90 less than 5 μm.

[0088] Comparative Example 5

[0089] This comparative example is similar to Example 5, except that in this comparative example, the pseudoboehmite with a colloidal index of 20% in Example 5 is replaced with an equimolar amount of pseudoboehmite with a colloidal index of 99% (conventional pseudoboehmite).

[0090] The adhesive provided in this comparative example contains 77 wt% adhesive, 20 wt% curing agent, and 3 wt% metal chelate modifier (calculated as metal oxide) based on 100% dry binder.

[0091] Comparative Example 6

[0092] This comparative example is similar to Example 5, except that the modifier in Example 5 is replaced with copper nitrate and lanthanum nitrate. The total molar amount of copper nitrate and lanthanum nitrate in this comparative example is the same as the total molar amount of copper oxide and lanthanum oxide in the copper and lanthanum bimetallic hydroxyethyl ethylenediamine triacetic acid chelate in Example 5, based on copper oxide and lanthanum oxide.

[0093] The adhesive provided in this comparative example contains 77 wt% adhesive, 20 wt% curing agent, and 3 wt% copper nitrate and lanthanum nitrate (as metal oxides) modifiers, based on 100% dry binder.

[0094] Comparative Example 7

[0095] This comparative example is similar to Example 5, except that a conventional reactor is used in this comparative example instead of the high-shear dispersing emulsifier in Example 5.

[0096] The adhesive provided in this comparative example contains 77 wt% adhesive, 20 wt% curing agent, and 3 wt% modifier, based on 100% dry binder.

[0097] Experimental Example

[0098] The binders prepared in Examples 1-6 and Comparative Examples 1-7 were used to replace conventional binder materials such as alumina sol, silica sol, and pseudo-boehmite in the production process of catalytic cracking catalysts, respectively. Catalytic cracking catalysts were prepared with 35% (mass percentage) Y-type molecular sieve, 23% (mass percentage) binder, and 42% (mass percentage) kaolin, resulting in a solid content of 35% (mass percentage). The specific methods are as follows:

[0099] First, kaolin and deionized water are mixed and slurried. Then, a binder and a Y-type molecular sieve slurry are added, and the mixture is stirred evenly to obtain a catalyst slurry. This slurry is then spray-dried. The spray-drying conditions are as follows: the furnace temperature of the spray tower is controlled at 580℃, and the exhaust gas temperature is controlled at 160℃. After calcining the obtained catalyst at 500℃ for 1 hour, it is ion-exchanged with an ammonium chloride solution to obtain the catalyst described in the example.

[0100] The binders prepared using the above embodiments and comparative examples were used to prepare catalysts according to the above methods, and their physicochemical properties were tested according to the following evaluation and analysis methods. The specific results are shown in Table 1.

[0101] Evaluation and analysis methods:

[0102] The surface area of ​​the catalyst was determined by the low-temperature nitrogen adsorption-desorption method (NB / SH / T 0959);

[0103] The pore volume of the catalyst was tested using the water droplet method (NB / SH / T 0955);

[0104] The catalyst attrition index was determined using the straight tube method (NB / SH / T 0964);

[0105] The thermal breakdown rate of the catalyst was tested on a small-scale fixed fluidized bed (all parts are made of stainless steel) abrasion system in the laboratory. During the experiment, the catalyst in the fluidized bed was continuously fluidized and abraded under the action of fluidized air or water vapor. The extremely fine powder particles abraded were discharged from the fluidized bed with the gas through the filter element, while larger particles were blocked by the filter element and remained in the fluidized bed for further abrasion. The gas guide tube has five air inlets with a diameter of 1 mm evenly distributed at the front end and around its perimeter, and the filter element has a filtration accuracy of 1 μm. The specific steps are as follows: First, weigh 100g of the prepared catalyst, denoted as w1, and add it to the fluidized bed. Heat the preheater to 150℃ and the fluidized bed temperature to 200℃. Turn on the air generator and adjust the gas flow rate to 40m / s. The apparent gas velocity inside the reactor is 0.8m / s. After 4 hours of fluidized bed wear, weigh the remaining catalyst in the reactor and denoted as w2. Change the preheater temperature to 650℃ and the fluidized bed temperature to 680℃, keeping other conditions unchanged, and repeat the measurement of the remaining catalyst weight, denoted as w3. The thermal collapse rate L is then:

[0106] L=(w2-w3) / w2×100%

[0107] The catalyst reaction performance was tested on a small fixed fluidized bed microreactor according to the method NB / SH / T0952-2017.

[0108] Table 1

[0109]

[0110] As can be seen from the data in the table above, compared with the comparative example, the catalyst prepared by using the binder and preparation method described in this invention instead of the traditional alumina sol and acidified boehmite still has high wear resistance, pore volume and specific surface area on the basis of high molecular sieve content.

[0111] Of course, the present invention may have other various embodiments. Without departing from the spirit and essence of the present invention, those skilled in the art can make various corresponding changes and modifications according to the present invention, but these corresponding changes and modifications should all fall within the protection scope of the claims of the present invention.

Claims

1. A high-strength, large-pore phosphorus-containing binder, characterized in that, It includes an adhesive, a curing agent, and a modifier; the adhesive includes phosphorus-containing compounds and aluminum-containing compounds; the curing agent includes γ-alumina precursors, acids, and alkylammonium salts; and the modifier is a metal chelate. Among them, the colloidal index of γ-alumina precursor is ≤50%; The modifier reacts with the adhesive in a high-shear dispersion emulsifier; The metal chelate is selected from at least one of phosphonic acid metal chelates, carboxylic acid metal chelates, and carbonyl metal chelates; the metal in the metal chelate is at least one of rare earth metal ions, transition metal ions, alkali metal ions, and alkaline earth metal ions. In the curing agent, the alkylammonium salt is selected from at least one of hexadecyltrimethylammonium bromide, hexadecylpyridine chloride, and dimethyloctadecylammonium chloride.

2. The high-strength, large-pore phosphorus-containing binder as described in claim 1, characterized in that, The carboxylic acid metal chelates include aminocarboxylic acid metal chelates and / or hydroxyaminocarboxylic acid metal chelates.

3. The high-strength, large-pore phosphorus-containing binder as described in claim 1, characterized in that, The metal chelate is a mixture of at least two metal chelates or a multi-metal chelate containing at least two metals.

4. The high-strength, large-pore phosphorus-containing binder as described in claim 1, characterized in that, The XRD patterns of the γ-alumina precursor with a colloidal index ≤50% showed characteristic peaks around 2θ of 14°, 28°, 38°, and 49°.

5. The high-strength, large-pore phosphorus-containing binder as described in claim 1, characterized in that, In the curing agent, the molar ratio of the acid to the γ-alumina precursor is 0.1 to 1:

1.

6. The high-strength, large-pore phosphorus-containing binder as described in claim 1, characterized in that, In the adhesive compound, the molar ratio of phosphorus in the phosphorus-containing compound to aluminum in the aluminum-containing compound is 1 to 10:

1.

7. The high-strength, large-pore phosphorus-containing binder as described in claim 1, characterized in that, Based on the dry basis weight of the high-strength, large-pore phosphorus-containing adhesive as 100%, the content of the adhesive is 60wt%~94wt%, the content of the curing agent is 5wt%~30wt%, and the content of the modifier is 1wt%~10wt%.

8. The high-strength, large-pore phosphorus-containing binder as described in claim 3, characterized in that, The metal in the metal chelate is a transition metal ion or a rare earth metal ion.

9. The high-strength, large-pore phosphorus-containing binder as described in claim 3, characterized in that, The molar ratio of the transition metal ion to the rare earth metal ion in the metal chelate is 5~15:

1.

10. The high-strength, large-pore phosphorus-containing binder as described in claim 5, characterized in that, In the curing agent, the molar ratio of the acid to the γ-alumina precursor is 0.2~0.5:

1.

11. The high-strength, large-pore phosphorus-containing binder as described in claim 6, characterized in that, In the adhesive compound, the molar ratio of phosphorus in the phosphorus-containing compound to aluminum in the aluminum-containing compound is 2~6:

1.

12. A method for preparing a high-strength, macroporous phosphorus-containing binder according to any one of claims 1-11, characterized in that, Includes the following steps: S1: Mix the γ-alumina precursor with an acid, then add an alkylammonium salt solution to react. After the reaction is complete, perform hydrothermal treatment to obtain a curing agent. S2: After mixing the curing agent with deionized water, add aluminum-containing compounds and phosphorus-containing compounds, control the pH of the system to ≤5, and then add it to a high-shear dispersing emulsifier for reaction. After the reaction is completed, a mixed slurry is obtained. S3: Add a modifier to the mixed slurry and react. After the reaction is complete, the high-strength, large-pore phosphorus-containing binder is obtained.

13. The preparation method according to claim 12, characterized in that, In step S1, the temperature of the hydrothermal treatment is 400–1000°C, the water vapor content is 10–80%, and the time is 1–10 hours.

14. The application of the high-strength, macroporous phosphorus-containing binder according to any one of claims 1-11 or the high-strength, macroporous phosphorus-containing binder according to claim 12 or 13 in the preparation of catalytic cracking catalysts, catalytic pyrolysis catalysts or additives.

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