A method for preparing a scorch-inhibiting passivating agent

Abstract

The present invention provides a method for preparing a coke-suppressing passivator, which belongs to the technical field of passivators and comprises the following steps: after antimony trioxide, water, amino acid and organic amine are mixed, hydrogen peroxide is added dropwise, reacted, and the temperature is lowered to obtain a passivation component A; under a nitrogen atmosphere, amino-modified SiO2, methacrylate and methanol are mixed, heated and stirred, solids are filtered out, and after Soxhlet extraction, vacuum drying is performed to obtain branched amino-modified SiO2; lanthanum phosphate, barium titanate, cerium sulfate, sulfuric acid solution and hydrogen peroxide are added to deionized water and stirred, sodium hydroxide is added to adjust the pH value, and a passivation component B is obtained; the passivation component A is mixed with the passivation component B, and the branched amino-modified SiO2 is added to mix, and the coke-suppressing passivator is obtained. The present invention can effectively inhibit the formation of coke, while reducing the hydrogen content and increasing the light oil yield.

Description

Technical Field

[0001] The invention relates to the technical field of passivators, and in particular to a method for preparing a scorch-inhibiting passivator. Background Art

[0002] Fluid catalytic cracking is commonly used to convert heavy crude oil fractions in refineries into light oil. Modern catalytic cracking catalysts are composed of zeolite, filler, matrix and binder. Processing heavy oil feedstocks containing high levels of contaminating metals (such as vanadium and nickel) will poison zeolite catalytic cracking catalysts. High levels of contaminating metals exist in the feedstock in the form of cyclohexane salts, inorganic salts, etc. During the catalytic cracking reaction, they are continuously deposited on the catalyst surface, which has a negative effect on the dehydrogenation of the catalyst.

[0003] The pollution of catalytic cracking catalysts mainly includes iron, nickel, copper, vanadium, sodium, etc., among which nickel and vanadium have the most serious impact on catalytic cracking. Vanadium and nickel in the feed exist in the form of organic complexes and porphyrins. Nickel porphyrin compounds will be reduced to metallic nickel during the coking process of residual oil. Metallic nickel is a highly active hydrogenation and dehydrogenation catalyst. Its toxicity is manifested in strong catalytic dehydrogenation. It can deoxygenate part of the feed and cracking products to generate oily polycyclic aromatic hydrocarbon polymers or coke. In addition, vanadium porphyrin compounds will also form oily polycyclic aromatic hydrocarbon polymers during the coke generation process, blocking the coke pores, making it difficult for the oil and gas in the coke to escape, resulting in a high coke yield, thereby increasing the hydrogen content and coke yield in the dry gas, and further leading to a decrease in the light oil yield. In addition, vanadium porphyrin compounds are converted into vanadium pentoxide in the regenerator. Under hydrothermal conditions, vanadium pentoxide with a melting point of about 690°C melts. This molten entity moves in the channels and cavities of the zeolite and reduces the accessibility of hydrocarbon molecules to the active sites, while blocking acid sites, leading to faster and deeper catalyst deactivation.

[0004] In the application document with publication number CN1762598A, a catalytic cracking metal passivator is prepared, and compounds containing boron and boron and phosphorus are used as passivators to make them have a significant passivation effect on nickel, so that the yield of the ideal product gasoline is increased by 2.5 to 4 percentage points, and the yield of hydrogen is reduced by 20% to 40%. However, the passivation of nickel alone is not enough to meet the actual use requirements. A multi-component passivator with good passivation effects on nickel and vanadium is needed to reduce the hydrogen content and coke yield.

[0005] Therefore, it is necessary to provide a method for preparing a scorch-inhibiting passivating agent to solve the problems existing in the above-mentioned prior art. Summary of the invention

[0006] In view of this, the present invention provides a method for preparing a coke-inhibiting passivating agent, which can effectively inhibit the formation of coke while reducing the hydrogen content and increasing the yield of light oil.

[0007] To achieve the above purpose, the specific scheme provided by the present invention is as follows:

[0008] A method for preparing a scorch-inhibiting passivating agent comprises the following steps:

[0009] S1. Mix antimony trioxide, water, amino acid and organic amine, add hydrogen peroxide dropwise, react, and cool to obtain passivation component A;

[0010] S2. Under a nitrogen atmosphere, the amino-modified SiO2, methacrylate and methanol are mixed, heated and stirred, the solid is filtered out, and after Soxhlet extraction, vacuum drying is performed to obtain branched amino-modified SiO2;

[0011] S3, adding lanthanum phosphate, barium titanate, cerium sulfate, sulfuric acid solution, and hydrogen peroxide into deionized water and stirring evenly, adding sodium hydroxide to adjust the pH value, and preparing a passivation component B;

[0012] S4. Mix the passivation component A and the passivation component B, add the branched amino-modified SiO2 and mix well to obtain a scorch-inhibiting passivator.

[0013] In the process of preparing the passivation component A, the present invention uses an amino acid with a Lewis acid-base functional group to replace the traditional organic acid as an auxiliary passivation component. The amino group and the carboxyl group contained in the amino acid molecule can form a stable chelate with the metal ion, which gives the amino acid a special property when forming a passivation film on the metal surface. The amino group, as a Lewis base, can provide an electron pair to form a coordination bond with the metal cation, and the carboxyl group, as a Lewis acid, can further form a stronger bond with the metal. This double complexation makes the passivation film formed by the amino acid on the metal surface more firm and stable, thereby enhancing the passivation effect. Antimony trioxide is oxidized to antimony pentoxide using hydrogen peroxide. Due to the high oxidation state, antimony pentoxide undergoes lattice substitution or forms an alloy with nickel, making the passivation layer on the surface more stable, inhibiting the destruction of the catalyst carrier by nickel, and weakening the dehydrogenation activity of nickel, thereby inhibiting the formation of coke.

[0014] The present invention mainly utilizes rare earth metals in the process of preparing the passivation component B, wherein lanthanum phosphate and cerium ions can effectively fix vanadium to form a stable V 4+ and V 5+Compounds, reduce the over-reduction of vanadium ions to generate lower valence vanadium compounds, to reduce the mobility of vanadium and further react with reactants to form coke. Although rare earth elements added by ion exchange can improve stability, they do not always prevent the catalyst from being deactivated by vanadium under higher concentrations of vanadium pollutants. The formation of vanadic acid will aggravate hydrothermal instability and eventually lead to the collapse of the catalyst structure. Therefore, the present invention introduces barium titanate, which contains barium oxide. The basic performance of its vanadic acid neutralization is enhanced through acid-base chemistry, and the damage of vanadic acid formation to the catalyst carrier is inhibited, so that the surface activity of the catalyst is more uniform and the accumulation of coke is inhibited. Titanium oxide fixes vanadium and increases the melting point of vanadium compounds to avoid overreaction on the catalyst surface. Using this compound at the same time, instead of BaO and TiO2, the negative impact of BaO on acid site neutralization can be reduced through high mobility under regeneration conditions, and barium titanate can reduce the adverse effects of high concentrations of titanium oxide in over-cracking reactions.

[0015] The present invention prepares branched amino-modified SiO2, copolymerizes amino-modified SiO2 with methacrylate to form a branched organosilicon complex, which has certain colloidal stability and dispersibility. The amino groups on the surface of amino-modified SiO2 and the larger specific surface area have strong complexing ability, and can form stable coordination complexes with metal ions such as nickel and vanadium. In this way, the activity of metal ions is limited, and then the ability of the metal ions to catalyze dehydrogenation reactions is suppressed, and the metal ions are not easy to participate in reduction reactions, especially cannot be reduced to metal nickel and metal vanadium. And through complexing and shielding effects, the branched amino-modified SiO2 can reduce the catalytic effect of metals, thereby effectively reducing the amount of coke generated. In addition, the branched amino-modified SiO2 can maintain the dispersed state of nickel and vanadium heavy metals in the liquid phase through its surface hydrophilicity and the polarity of amino groups during the coking process, and the branched amino-modified SiO2, as a colloidal stabilizer, can avoid its aggregation or precipitation at high temperatures, thereby reducing metal deposition, and further reducing the yield of coke.

[0016] Optionally, in step S1, the amino acid is one of L-aspartic acid, glutamic acid and glycine, and the organic amine is one of diethanolamine and hexamethylenetetramine.

[0017] Optionally, in step S1, after antimony trioxide, water, amino acid and organic amine are mixed, hydrogen peroxide with a mass concentration of 30% is added dropwise and the reaction temperature is controlled to be lower than 95° C. After the addition is completed, the reaction is carried out for 30 to 50 minutes and the temperature is cooled to room temperature to obtain the passivation component A.

[0018] Optionally, in step S2, the amino-modified SiO2 is prepared by mixing silica gel, aminopropyltriethoxysilane and toluene solution, stirring at 70°C for 6-10 hours, filtering out the solid product and transferring it to a Soxhlet extraction apparatus, extracting it under reflux in toluene and ethanol for 10 hours respectively, and then vacuum drying it at 50-70°C for 24-36 hours.

[0019] The invention uses aminopropyltriethoxysilane to introduce amino groups into the surface of silica gel, and forms stable amino-modified SiO2 through hydrolysis and condensation reactions.

[0020] Optionally, the heating and stirring temperature in step S2 is 50-60°C and the time is 24-48 hours. After heating and stirring, the solid product is filtered out and transferred to a Soxhlet extraction apparatus. After reflux extraction in ethanol and tetrahydrofuran for 24-36 hours, the product is vacuum dried at 50-70°C for 24-36 hours to obtain branched amino-modified SiO2.

[0021] Optionally, the lanthanum phosphate in step S3 is prepared by heating lanthanum chloride and ammonium phosphate under 0.1 MPa low-pressure steam, reacting at 90-95° C., and vacuum drying for 12-24 hours.

[0022] Optionally, the barium titanate in step S3 is prepared by mixing titanium nitrate solution, barium nitrate solution and glycine, heating to 90° C. until it becomes viscous, and then heating to 300° C. to obtain barium titanate powder; wherein the titanium nitrate solution is obtained by mixing titanium tetraisopropoxide and a nitric acid solution with a mass concentration of 3%.

[0023] In the process of preparing barium titanate, glycine is added to form a coordination complex with metal ions (barium ions, titanium ions) through its amino and carboxyl groups. During the heating process, the dehydration of glycine promotes and enhances the interaction between the reactants, and organic matter is removed by heating at a high temperature of 300°C.

[0024] Optionally, in step S3, the mass concentration of the sulfuric acid solution is 98%, and the mass concentration of the hydrogen peroxide is 30%.

[0025] Optionally, sodium hydroxide is added in step S3 to adjust the pH value to 2.5-3.

[0026] Optionally, the scorch-suppressing passivator comprises the following raw materials in parts by weight: 60-70 parts of passivation component A, 20-30 parts of passivation component B, and 5-10 parts of branched amino-modified SiO2.

[0027] The above technical solution of the present invention includes at least the following beneficial effects:

[0028] 1. In the process of preparing the passivation component A, the present invention uses an amino acid with a Lewis acid-base functional group instead of a traditional organic acid as an auxiliary passivation component. The amino group, as a Lewis base, can provide an electron pair to form a coordination bond with a metal cation, while the carboxyl group, as a Lewis acid, can further form a stronger bond with the metal, thereby enhancing the passivation effect. Antimony trioxide is oxidized to antimony pentoxide using hydrogen peroxide. Antimony pentoxide and nickel undergo lattice substitution or form an alloy, making the surface passivation layer more stable, inhibiting the damage of nickel to the catalyst carrier, and weakening the dehydrogenation activity of nickel, thereby inhibiting the formation of coke.

[0029] 2. The present invention mainly utilizes rare earth metals in the process of preparing the passivation component B, among which lanthanum phosphate and cerium ions can effectively fix vanadium to form a stable V 4+ and V 5+ Compounds reduce the formation of coke by reaction with reactants, and the barium oxide contained in barium titanate neutralizes vanadic acid, thereby inhibiting the formation of vanadic acid to damage the catalyst carrier, while titanium oxide fixes vanadium and increases the melting point of vanadium compounds, avoiding excessive reaction on the catalyst surface and further reducing the formation of coke.

[0030] 3. The present invention prepares branched amino-modified SiO2, which has certain colloidal stability and dispersibility. Through complexation and shielding, branched amino-modified SiO2 can reduce the catalytic effect of metal nickel and vanadium, thereby effectively reducing the amount of coke generated and weakening the dehydrogenation activity. In addition, branched amino-modified SiO2 can act as a colloidal stabilizer during the coking process through its surface hydrophilicity and the polarity of the amino group, maintaining the dispersed state of nickel and vanadium heavy metals in the liquid phase, avoiding their aggregation or precipitation at high temperature, thereby reducing metal deposition and further reducing the yield of coke. DETAILED DESCRIPTION

[0031] In order to make the purpose, technical solution and advantages of the embodiment of the present invention clearer, the technical solution of the embodiment of the present invention will be clearly and completely described in combination with the embodiment of the present invention. Obviously, the described embodiment is a part of the embodiment of the present invention, not all the embodiments. Based on the described embodiment of the present invention, all other embodiments obtained by ordinary technicians in this field belong to the scope of protection of the present invention.

[0032] Example 1

[0033] After 20 parts of antimony trioxide, 45 parts of water, 2 parts of L-aspartic acid and 5 parts of diethanolamine are uniformly mixed, 5 parts of hydrogen peroxide with a mass concentration of 30% are added dropwise, the reaction temperature is controlled to be lower than 95°C, and the reaction is carried out for 30 minutes after the addition is completed, and the temperature is cooled to room temperature to obtain a passivation component A;

[0034] 20 parts of lanthanum chloride and 20 parts of ammonium phosphate were heated under 0.1MPa low-pressure steam, reacted at 90°C, and vacuum dried for 24 hours to obtain lanthanum phosphate. 10 parts of titanium tetraisopropoxide were mixed with 15 parts of 3% nitric acid solution to obtain titanium nitrate solution. 5 parts of titanium nitrate solution, 5 parts of barium nitrate solution, and 15 parts of glycine were mixed and heated to 90°C until it became viscous. Finally, the mixture was heated to 300°C for ignition and combustion reaction to obtain barium titanate powder.

[0035] Mix 5 parts of silica gel, 5 parts of aminopropyltriethoxysilane, and 15 parts of toluene solution, stir at 70°C for 6 hours, filter out the solid product and transfer it to a Soxhlet extraction device, reflux extract in toluene and ethanol for 10 hours, and vacuum dry at 50°C for 36 hours to obtain amino-modified SiO2. Under a nitrogen atmosphere, 4 parts of amino-modified SiO2, 3 parts of methacrylate, and 25 parts of methanol are mixed as solvents, and stirred at 50°C for 48 hours to fully react. Then filter out the solid product and transfer it to a Soxhlet extraction device, reflux extract in ethanol and tetrahydrofuran for 24 hours, and vacuum dry at 50°C for 36 hours to obtain branched amino-modified SiO2.

[0036] At room temperature, 15 parts of lanthanum phosphate, 5 parts of barium titanate, 10 parts of cerium sulfate, 10 parts of sulfuric acid solution with a mass concentration of 98%, and 10 parts of hydrogen peroxide with a mass concentration of 30% were added to 40 parts of deionized water, stirred evenly, and an appropriate amount of sodium hydroxide was added to adjust the pH value to 2.5 to obtain passivation component B. 60 parts of passivation component A and 20 parts of passivation component B were mixed evenly, and 5 parts of branched amino-modified SiO2 were added and mixed to obtain a scorch-inhibiting passivator.

[0037] Example 2

[0038] 35 parts of antimony trioxide, 45 parts of water, 5 parts of glutamic acid and 15 parts of hexamethylenetetramine were mixed evenly, and 10 parts of hydrogen peroxide with a mass concentration of 30% were added dropwise, and the reaction temperature was controlled to be lower than 95°C. After the addition was completed, the reaction was carried out for 50 minutes and then cooled to room temperature to obtain a passivation component A;

[0039] 20 parts of lanthanum chloride and 20 parts of ammonium phosphate were heated under 0.1MPa low-pressure steam, reacted at 95°C, and vacuum dried for 12 hours to obtain lanthanum phosphate. 10 parts of titanium tetraisopropoxide were mixed with 15 parts of 3% nitric acid solution to obtain titanium nitrate solution. 5 parts of titanium nitrate solution, 5 parts of barium nitrate solution, and 15 parts of glycine were mixed and heated to 90°C until it became viscous. Finally, the mixture was heated to 300°C for ignition and combustion reaction to obtain barium titanate powder.

[0040] Mix 5 parts of silica gel, 5 parts of aminopropyltriethoxysilane, and 15 parts of toluene solution, stir at 70°C for 10 hours, filter out the solid product and transfer it to a Soxhlet extraction device, reflux extract in toluene and ethanol for 10 hours, and vacuum dry at 70°C for 24 hours to obtain amino-modified SiO2. Under a nitrogen atmosphere, 4 parts of amino-modified SiO2, 3 parts of methacrylate, and 25 parts of methanol as solvents are mixed evenly and stirred at 60°C for 24 hours to fully react. Then filter out the solid product and transfer it to a Soxhlet extraction device, reflux extract in ethanol and tetrahydrofuran for 36 hours, and vacuum dry at 70°C for 24 hours to obtain branched amino-modified SiO2.

[0041] At room temperature, 20 parts of lanthanum phosphate, 10 parts of barium titanate, 15 parts of cerium sulfate, 15 parts of sulfuric acid solution with a mass concentration of 98%, and 20 parts of hydrogen peroxide with a mass concentration of 30% were added to 50 parts of deionized water, stirred evenly, and an appropriate amount of sodium hydroxide was added to adjust the pH value to 3 to obtain a passivation component B. 70 parts of passivation component A and 30 parts of passivation component B were mixed evenly, and 10 parts of branched amino-modified SiO2 were added and mixed to obtain a scorch-inhibiting passivator.

[0042] Example 3

[0043] After 30 parts of antimony trioxide, 45 parts of water, 3 parts of glycine and 10 parts of hexamethylenetetramine are uniformly mixed, 8 parts of hydrogen peroxide with a mass concentration of 30% are added dropwise, the reaction temperature is controlled below 95°C, the reaction is carried out for 40 minutes after the addition is completed, and the temperature is cooled to room temperature to obtain the passivation component A.

[0044] 20 parts of lanthanum chloride and 20 parts of ammonium phosphate were heated under 0.1MPa low-pressure steam, reacted at 95°C, and vacuum dried for 16 hours to obtain lanthanum phosphate. 10 parts of titanium tetraisopropoxide were mixed with 15 parts of 3% nitric acid solution to obtain titanium nitrate solution. 5 parts of titanium nitrate solution, 5 parts of barium nitrate solution, and 15 parts of glycine were mixed and heated to 90°C until it became viscous. Finally, the mixture was heated to 300°C for ignition and combustion reaction to obtain barium titanate powder.

[0045] Mix 5 parts of silica gel, 5 parts of aminopropyltriethoxysilane, and 15 parts of toluene solution, stir at 70°C for 8 hours, filter out the solid product and transfer it to a Soxhlet extraction device, reflux extract in toluene and ethanol for 10 hours, and vacuum dry at 60°C for 30 hours to obtain amino-modified SiO2. Under a nitrogen atmosphere, 4 parts of amino-modified SiO2, 3 parts of methacrylate, and 25 parts of methanol are mixed as solvents, and stirred at 60°C for 48 hours to fully react. Then filter out the solid product and transfer it to a Soxhlet extraction device, reflux extract in ethanol and tetrahydrofuran for 36 hours, and vacuum dry at 70°C for 30 hours to obtain branched amino-modified SiO2.

[0046] At room temperature, 17 parts of lanthanum phosphate, 8 parts of barium titanate, 13 parts of cerium sulfate, 12 parts of sulfuric acid solution with a mass concentration of 98%, and 15 parts of hydrogen peroxide with a mass concentration of 30% were added to 45 parts of deionized water, stirred evenly, and an appropriate amount of sodium hydroxide was added to adjust the pH value to 2.7 to obtain a passivation component B. 65 parts of passivation component A and 25 parts of passivation component B were mixed evenly, and 10 parts of branched amino-modified SiO2 were added and mixed to obtain a scorch-inhibiting passivator.

[0047] Example 4

[0048] After 25 parts of antimony trioxide, 45 parts of water, 4 parts of L-aspartic acid and 12 parts of organic amine are uniformly mixed, 7 parts of hydrogen peroxide with a mass concentration of 30% are added dropwise, the reaction temperature is controlled to be lower than 95°C, the reaction is carried out for 50 minutes after the addition is completed, and the temperature is cooled to room temperature to obtain a passivation component A;

[0049] 20 parts of lanthanum chloride and 20 parts of ammonium phosphate were heated under 0.1MPa low-pressure steam, reacted at 90°C, and vacuum dried for 20 hours to obtain lanthanum phosphate. 10 parts of titanium tetraisopropoxide were mixed with 15 parts of 3% nitric acid solution to obtain titanium nitrate solution. 5 parts of titanium nitrate solution, 5 parts of barium nitrate solution, and 15 parts of glycine were mixed and heated to 90°C until it became viscous. Finally, the mixture was heated to 300°C for ignition and combustion reaction to obtain barium titanate powder.

[0050] Mix 5 parts of silica gel, 5 parts of aminopropyltriethoxysilane, and 15 parts of toluene solution, stir at 70°C for 6-10 hours, filter out the solid product and transfer it to a Soxhlet extraction device, reflux extract in toluene and ethanol for 10 hours, and vacuum dry at 60°C for 28 hours to obtain amino-modified SiO2. Under a nitrogen atmosphere, 4 parts of amino-modified SiO2, 3 parts of methacrylate, and 25 parts of methanol as solvents are mixed evenly and stirred at 50-60°C for 24-48 hours to fully react. Then filter out the solid product and transfer it to a Soxhlet extraction device, reflux extract in ethanol and tetrahydrofuran for 32 hours, and vacuum dry at 60°C for 24 hours to obtain branched amino-modified SiO2.

[0051] At room temperature, 15 parts of lanthanum phosphate, 10 parts of barium titanate, 15 parts of cerium sulfate, 10 parts of sulfuric acid solution with a mass concentration of 98%, and 10 parts of hydrogen peroxide with a mass concentration of 30% were added to 50 parts of deionized water, stirred evenly, and an appropriate amount of sodium hydroxide was added to adjust the pH value to 2.5 to obtain a passivation component B. 70 parts of passivation component A and 20 parts of passivation component B were mixed evenly, and 6 parts of branched amino-modified SiO2 were added and mixed to obtain a scorch-inhibiting passivator.

[0052] Example 5

[0053] 30 parts of antimony trioxide, 45 parts of water, 4 parts of glutamic acid and 13 parts of hexamethylenetetramine were mixed evenly, and 8 parts of hydrogen peroxide with a mass concentration of 30% were added dropwise, and the reaction temperature was controlled to be lower than 95°C. After the addition was completed, the reaction was carried out for 45 minutes and then cooled to room temperature to obtain a passivation component A.

[0054] 20 parts of lanthanum chloride and 20 parts of ammonium phosphate were heated under 0.1MPa low-pressure steam, reacted at 95°C, and vacuum dried for 18 hours to obtain lanthanum phosphate. 10 parts of titanium tetraisopropoxide were mixed with 15 parts of 3% nitric acid solution to obtain titanium nitrate solution. 5 parts of titanium nitrate solution, 5 parts of barium nitrate solution, and 15 parts of glycine were mixed and heated to 90°C until it became viscous. Finally, the mixture was heated to 300°C for ignition and combustion reaction to obtain barium titanate powder.

[0055] Mix 5 parts of silica gel, 5 parts of aminopropyltriethoxysilane, and 15 parts of toluene solution, stir at 70°C for 7h, filter out the solid product and transfer it to a Soxhlet extraction device, reflux extract in toluene and ethanol for 10h, and vacuum dry at 70°C for 28h to obtain amino-modified SiO2. Under a nitrogen atmosphere, 4 parts of amino-modified SiO2, 3 parts of methacrylate, and 25 parts of methanol as solvents are mixed evenly and stirred at 55°C for 48h to fully react. Then filter out the solid product and transfer it to a Soxhlet extraction device, reflux extract in ethanol and tetrahydrofuran for 24~36h, and vacuum dry at 65°C for 26h to obtain branched amino-modified SiO2.

[0056] At room temperature, 17 parts of lanthanum phosphate, 9 parts of barium titanate, 11 parts of cerium sulfate, 13 parts of sulfuric acid solution with a mass concentration of 98%, and 18 parts of hydrogen peroxide with a mass concentration of 30% were added to 45 parts of deionized water, stirred evenly, and an appropriate amount of sodium hydroxide was added to adjust the pH value to 2.5 to obtain a passivation component B. 65 parts of passivation component A and 22 parts of passivation component B were mixed evenly, and 8 parts of branched amino-modified SiO2 were added and mixed to obtain a scorch-inhibiting passivator.

[0057] Example 6

[0058] After 30 parts of antimony trioxide, 45 parts of water, 4 parts of glycine and 11 parts of organic amine are uniformly mixed, 5 parts of hydrogen peroxide with a mass concentration of 30% are added dropwise, the reaction temperature is controlled to be lower than 95°C, the reaction is carried out for 40 minutes after the addition is completed, and the temperature is cooled to room temperature to obtain the passivation component A;

[0059] 20 parts of lanthanum chloride and 20 parts of ammonium phosphate were heated under 0.1MPa low-pressure steam, reacted at 95°C, and vacuum dried for 16 hours to obtain lanthanum phosphate. 10 parts of titanium tetraisopropoxide were mixed with 15 parts of 3% nitric acid solution to obtain titanium nitrate solution. 5 parts of titanium nitrate solution, 5 parts of barium nitrate solution, and 15 parts of glycine were mixed and heated to 90°C until it became viscous. Finally, the mixture was heated to 300°C for ignition and combustion reaction to obtain barium titanate powder.

[0060] Mix 5 parts of silica gel, 5 parts of aminopropyltriethoxysilane, and 15 parts of toluene solution, stir at 70°C for 8 hours, filter out the solid product and transfer it to a Soxhlet extraction device, reflux extract in toluene and ethanol for 10 hours, and vacuum dry at 70°C for 30 hours to obtain amino-modified SiO2. Under a nitrogen atmosphere, 4 parts of amino-modified SiO2, 3 parts of methacrylate, and 25 parts of methanol are mixed as solvents, and stirred at 60°C for 36 hours to fully react. Then filter out the solid product and transfer it to a Soxhlet extraction device, reflux extract in ethanol and tetrahydrofuran for 30 hours, and vacuum dry at 70°C for 24 hours to obtain branched amino-modified SiO2.

[0061] At room temperature, 16 parts of lanthanum phosphate, 7 parts of barium titanate, 12 parts of cerium sulfate, 10 parts of sulfuric acid solution with a mass concentration of 98%, and 20 parts of hydrogen peroxide with a mass concentration of 30% were added to 45 parts of deionized water, stirred evenly, and an appropriate amount of sodium hydroxide was added to adjust the pH value to 3 to obtain a passivation component B. 65 parts of passivation component A and 25 parts of passivation component B were mixed evenly, and 5 parts of branched amino-modified SiO2 were added and mixed to obtain a scorch-inhibiting passivator.

[0062] The present invention also carries out comparative examples and related tests.

[0063] Comparative Example 1

[0064] Compared with Example 3, the difference is that no amino acid is added when preparing the passivation component A, and the other components and preparation steps are completely the same, and a coke-suppressing passivating agent is prepared.

[0065] Comparative Example 2

[0066] Compared with Example 3, the difference is that lanthanum phosphate is not added when preparing the passivation component B, and the other components and preparation steps are completely the same, and a coke-suppressing passivating agent is prepared.

[0067] Comparative Example 3

[0068] Compared with Example 3, the difference is that barium titanate is not added when preparing the passivation component B, and the other components and preparation steps are completely the same, and a coke-suppressing passivating agent is prepared.

[0069] Comparative Example 4

[0070] Compared with Example 3, the difference is that branched amino-modified SiO2 is not prepared, and commercial SiO2 powder is directly added. The other components and preparation steps are completely the same, and a coke-suppressing passivating agent is prepared.

[0071] Performance testing

[0072] The coke-suppressing passivators prepared in Examples 1 to 6 and Comparative Examples 1 to 4 were tested for density, freezing point and kinematic viscosity according to the test method of GB / T1884-2000 laboratory determination method for density of crude oil and liquid petroleum products (densitometer method), GB / T510-1983 petroleum product freezing point determination method, GB / T265-1988 petroleum product kinematic viscosity determination method and dynamic viscosity calculation method. The basic performance test results are shown in Table 1.

[0073] Table 1

[0074]

[0075] As shown in Table 1, the coke-suppressing passivators prepared in Examples 1 to 6 have densities of 1.1 to 1.3 at 20°C, freezing points ≤-13°C, and kinematic viscosities ≤10 at 40°C, all of which meet national standards.

[0076] In a fixed fluidized bed apparatus, the zeolite catalyst was passivated with the coke-suppressing passivator prepared in Examples 1 to 6 and Comparative Examples 1 to 4, and then the crude oil was tested, wherein the reaction temperature was 480° C., the reaction pressure was normal pressure, the agent-oil ratio was 4.2, and the oil feed rate was 800 g / h. The passivation effect was evaluated, and the results are shown in Table 2.

[0077] Table 2

[0078]

[0079] As shown in Table 1, the coke-suppressing passivators prepared by Examples 1 to 6 have significantly lower hydrogen and coke yields, and significantly higher light oil yields and total conversion rates than Comparative Examples 1 to 4. Among them, Comparative Examples 3 and 4 have a greater impact on hydrogen and coke yields due to the absence of barium titanate and branched amino-modified SiO2, which further greatly reduces the light oil yield and total conversion rate.

[0080] The above are preferred embodiments of the present invention. It should be pointed out that, for ordinary technicians in this technical field, several improvements and modifications can be made without departing from the principles of the present invention. These improvements and modifications should also be regarded as within the scope of protection of the present invention.

Claims

1. A method for preparing a scorch-suppressing passivating agent, characterized in that: The following steps are involved: S1. After antimony trioxide, water, amino acid and organic amine are mixed, hydrogen peroxide with a mass concentration of 30% is added dropwise and the reaction temperature is controlled to be lower than 95°C. After the addition is completed, the reaction is carried out for 30 to 50 minutes and then cooled to room temperature to obtain passivation component A; S2. Under a nitrogen atmosphere, the amino-modified SiO2, methacrylate and methanol are mixed, heated and stirred, the solid is filtered out, and after Soxhlet extraction, vacuum drying is performed to obtain branched amino-modified SiO2; S3, adding lanthanum phosphate, barium titanate, cerium sulfate, sulfuric acid solution, and hydrogen peroxide into deionized water and stirring evenly, adding sodium hydroxide to adjust the pH value, and preparing a passivation component B; S4, mixing the passivation component A and the passivation component B, adding the branched amino-modified SiO2 and mixing, to obtain a scorch-inhibiting passivator; The scorch-inhibiting passivator comprises the following raw materials in parts by weight: 60-70 parts of a passivation component A, 20-30 parts of a passivation component B, and 5-10 parts of branched amino-modified SiO2.

2. The method for preparing a scorch-suppressing passivating agent according to claim 1, characterized in that: In step S1, the amino acid is one of L-aspartic acid, glutamic acid or glycine, and the organic amine is one of diethanolamine or hexamethylenetetramine.

3. The method for preparing a scorch-suppressing passivating agent according to claim 1, characterized in that: In step S2, the amino-modified SiO2 is prepared by mixing silica gel, aminopropyltriethoxysilane and toluene solution, stirring at 70°C for 6-10 hours, filtering out the solid product and transferring it to a Soxhlet extraction apparatus, extracting it in toluene and ethanol under reflux for 10 hours respectively, and then vacuum drying it at 50-70°C for 24-36 hours.

4. The method for preparing a scorch-suppressing passivating agent according to claim 1, characterized in that: In the step S2, the heating and stirring temperature is 50-60° C. and the time is 24-48 hours. After heating and stirring, the solid product is filtered out and transferred to a Soxhlet extraction apparatus. After reflux extraction in ethanol and tetrahydrofuran for 24-36 hours, the solid product is vacuum dried at 50-70° C. for 24-36 hours to obtain branched amino-modified SiO2.

5. The method for preparing a scorch-suppressing passivating agent according to claim 1, characterized in that: The lanthanum phosphate in step S3 is prepared by heating lanthanum chloride and ammonium phosphate under 0.1 MPa low-pressure steam, reacting at 90-95° C., and vacuum drying for 12-24 hours.

6. The method for preparing a scorch-suppressing passivating agent according to claim 1, characterized in that: The barium titanate in step S3 is prepared by mixing titanium nitrate solution, barium nitrate solution and glycine, heating to 90° C. until it becomes viscous, and then heating to 300° C. to obtain barium titanate powder; wherein the titanium nitrate solution is obtained by mixing titanium tetraisopropoxide and a nitric acid solution with a mass concentration of 3%.

7. The method for preparing a scorch-suppressing passivating agent according to claim 1, characterized in that: In step S3, the mass concentration of the sulfuric acid solution is 98%, and the mass concentration of the hydrogen peroxide is 30%.

8. The method for preparing a scorch-suppressing passivating agent according to claim 1, characterized in that: In step S3, sodium hydroxide is added to adjust the pH value to 2.5-3.

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