Process for reducing catalyst production sludge emissions
By controlling pH and temperature, the filtrate after NaY molecular sieve synthesis and filtration was mixed with a dispersion and an aluminum source to prepare a rare earth-containing composite active mesoporous and macroporous material. This solved the problem of NaY mother liquor utilization and improved the heavy oil cracking performance and light oil yield of the catalyst.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Patents(China)
- Current Assignee / Owner
- CHINA PETROLEUM & CHEMICAL CORP
- Filing Date
- 2022-10-31
- Publication Date
- 2026-07-14
AI Technical Summary
Existing technologies make it difficult to effectively utilize the filtrate after NaY molecular sieve synthesis and filtration to prepare high-performance mesoporous and macroporous silica-alumina materials, resulting in resource waste and difficulties in disposing of sludge.
By mixing the filtrate after synthesizing and filtering NaY molecular sieves with a first dispersion, a second dispersion, and an aluminum source, controlling the pH value to 9-11, the reaction temperature to 30-90℃, and the reaction time to 1-24 hours, followed by exchange and filtration with a washing solution with a pH value greater than 7, rare earth-containing composite active mesoporous and macroporous materials are prepared.
This approach enables the effective utilization of NaY mother liquor, prepares mesoporous and macroporous materials with good performance, improves the hydrothermal stability and heavy oil cracking capacity of the catalyst, and enhances the light oil yield of the catalyst.
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Abstract
Description
Technical Field
[0001] This invention belongs to the field of environmental protection technology and relates to a method for reducing the generation of gum residue in catalyst production. Background Technology
[0002] Modified Y-type molecular sieves possess high hydrothermal stability and are used as active components in numerous petrochemical reaction catalysts. Currently, Y-type molecular sieves are primarily synthesized artificially. This process involves first forming a crystallization mixture from NaY molecular sieve raw materials, then crystallizing it to form a crystallized product. This crystallized product is then filtered to obtain NaY molecular sieves and the filtrate (NaY mother liquor). NaY molecular sieves can be modified through methods such as ion exchange, ultrastabilization treatment, and rare earth deposition to obtain modified molecular sieve products that meet specific requirements.
[0003] Currently, manufacturers typically collect and process the various filtrates generated during the synthesis and modification of NaY molecular sieves, followed by sedimentation, filtration, and slag removal to obtain waste residue primarily composed of Al2O3 and SiO2. This waste residue is difficult to utilize and is currently usually disposed of directly, resulting in a waste of resources such as Si and Al.
[0004] The filtrate after NaY molecular sieve synthesis and filtration is the liquid obtained after filtration following the crystallization of NaY molecular sieves. Also known as NaY mother liquor, it contains incompletely crystallized molecular sieves, small-particle Y-type molecular sieves, unreacted free silica, and a small amount of alumina. Some studies have attempted to prepare aluminosilicate materials from the filtrate after NaY molecular sieve synthesis. However, because NaY mother liquor differs from conventional silicon-containing raw materials, preparing a high-performance aluminosilicate material suitable for cracking catalysts is challenging. Aluminosilicate materials prepared using existing methods from NaY synthesis mother liquor still perform poorly in heavy oil catalytic cracking. As crude oil becomes heavier, it is desirable for the catalyst matrix material to have mesoporous or macroporous structures to crack large hydrocarbon molecules. However, current technology cannot arbitrarily synthesize high-performance mesoporous or macroporous aluminosilicate materials from catalytic cracking catalyst residue or NaY synthesis mother liquor. Summary of the Invention
[0005] The technical problem to be solved by the present invention is to provide a method for synthesizing mesoporous and macroporous materials from silicon and aluminum sources in the filtrate after NaY molecular sieve synthesis filtration. This method can use the filtrate after NaY synthesis filtration to synthesize rare earth-containing composite active mesoporous and macroporous materials (also referred to as composite active mesoporous and macroporous materials in this invention).
[0006] In a first aspect, this invention provides a method for synthesizing rare earth-containing composite active mesoporous and macroporous materials using molecular sieve synthesis filtrate, comprising the following steps:
[0007] (1) The filtrate after the synthesis and filtration of NaY molecular sieve is mixed with the first dispersion, the second dispersion and the aluminum source, and the pH value of the mixture is controlled to be 9-11. The reaction is carried out at a reaction temperature of 30-90℃ for 1-24 hours.
[0008] (2) Filtration, contact exchange with washing liquid with pH value greater than 7, wash as desired, filter, and obtain rare earth composite active mesoporous material.
[0009] According to the above technical solution, the first dispersion has a solid content of 0.5-2 wt% and a pH value of 1-4. Preferably, the dry chemical composition of the solid product obtained by drying the first dispersion includes 1-5 wt% Na2O, 35-50 wt% Al2O3, 40-55 wt% SiO2 and 2-8 wt% RE2O3.
[0010] According to any of the above technical solutions, the second dispersion has a solid content of 0.1-2 wt% and a pH value of 2-4; preferably, the dry basis chemical composition of the solid product obtained by drying the second dispersion includes 0.5-2.5 wt% Na2O, 5-30 wt% Al2O3, 20-50 wt% SiO2 and 40-70 wt% RE2O3.
[0011] According to any of the above technical solutions, the free SiO2 concentration in the filtrate after the synthesis and filtration of the NaY molecular sieve is 10-60 g / L, and the suspended solids content is 5000-15000 mg / L.
[0012] According to any of the above technical solutions, the aluminum source is, for example, one or more of Al(NO3)3, AlCl3, Al2(SO4)3, boehmite, and aluminum sol. The aluminum source can be formed into an aluminum source dispersion and then mixed with other materials.
[0013] According to any of the above technical solutions, the filtrate after NaY molecular sieve synthesis and filtration, the first dispersion, the second dispersion, and the aluminum source are respectively added to a reaction vessel for mixing. The aluminum source can be added by adding the aluminum source dispersion. The reaction vessel can be a stirred tank.
[0014] Preferably, the first and second dispersions are not added to the reactor before the filtrate is added after the NaY molecular sieve synthesis and filtration.
[0015] According to any of the above technical solutions, in one embodiment, the filtrate after NaY molecular sieve synthesis and filtration, the first dispersion, the second dispersion, and the aluminum source are respectively added to a reaction vessel for mixing. For example, the filtrate after NaY molecular sieve synthesis and filtration, the first dispersion, and the second dispersion are added to the reaction vessel in a parallel flow simultaneously, and then the aluminum source is added; or, after the filtrate after NaY molecular sieve synthesis and filtration is added to the reaction vessel, the first dispersion, the second dispersion, and the aluminum source dispersion are added to the reaction vessel in a parallel flow; or, after the filtrate after NaY molecular sieve synthesis and filtration is added to the reaction vessel, the first dispersion, the second dispersion, and the aluminum source dispersion are added in a parallel flow or separately, and then the aluminum source is added; or, the filtrate after NaY molecular sieve synthesis and filtration, the first dispersion, the second dispersion, and the aluminum source dispersion are added to the reaction vessel sequentially.
[0016] More preferably, the filtrate after the synthesis and filtration of NaY molecular sieve is first added to the reactor, and then the first dispersion, the second dispersion and the dispersion of the aluminum source are added to the reactor in parallel.
[0017] According to any of the above technical solutions, the mixture formed by the filtrate after the synthesis and filtration of the NaY molecular sieve, the first dispersion, the second dispersion, and the aluminum source has the following weight ratios: SiO2:Al2O3 is 25-65:20-50, RE2O3:Al2O3 is 2-20:20-50; Na2O:Al2O3 is 0.5-5:20-50.
[0018] According to any of the above technical solutions, preferably, the total mass of SiO2, Al2O3, and RE2O3 in the filtrate after NaY molecular sieve synthesis filtration, the first dispersion, and the second dispersion (including SiO2 and Al2O3 in the filtrate after NaY molecular sieve synthesis filtration, SiO2, Al2O3, RE2O3 in the first dispersion, and SiO2, Al2O3, and RE2O3 in the second dispersion) to the weight ratio of the aluminum source based on Al2O3 is 1 to 20:1.
[0019] In one embodiment, the solid content of the mixture formed by the filtrate after synthesis and filtration of the NaY molecular sieve, the first dispersion, the second dispersion, and the aluminum source is 0.5 to 10% by weight, for example, 1 to 8% by weight, for example, 1.5 to 5% by weight or 1.5% to 3.5% by weight.
[0020] Preferably, the amounts of the filtrate after the synthesis and filtration of the NaY molecular sieve, the first dispersion, the second dispersion, and the aluminum source are such that the obtained rare earth-containing composite active mesoporous material has the following weight composition (based on dry weight): SiO2 25-65 wt%, for example 30-65 wt%, Al2O3 20-50 wt%, for example 20-45 wt%, Na2O 0.5-5 wt%, and RE2O3 2-20 wt%.
[0021] According to any of the above technical solutions, preferably, the first dispersion is a filtrate modified with ultrastable molecular sieve, wherein the suspended solids concentration in the ultrastable molecular sieve filtrate is 5000-15000 mg / L; the second dispersion is a high rare earth concentration molecular sieve double crosslinking filtrate, wherein the dry basis concentration in the high rare earth concentration molecular sieve double crosslinking filtrate is 3000-15000 mg / L.
[0022] According to the above technical solution, the filtrate after the molecular sieve ultra-stable modification is the filtrate produced by washing after hydrothermal ultra-stable modification and / or silicon tetrachloride ultra-stable modification; the high rare earth concentration molecular sieve secondary exchange filtrate is, for example, the filtrate produced by secondary exchange of modified Y-type molecular sieve with rare earth content higher than 15% by weight and exchange liquid with rare earth oxide content higher than 1% by weight.
[0023] According to any of the above technical solutions, the method for synthesizing rare earth-containing composite active mesoporous and macroporous materials using molecular sieve synthesis filtrate includes the following steps:
[0024] (B1) The pH value of the filtrate after the molecular sieve ultra-stable modification was adjusted to 1-4 using inorganic acid to obtain the adjusted molecular sieve ultra-stable modified filtrate.
[0025] (B2) The pH value of the high rare earth concentration molecular sieve double cross-linked filtrate was adjusted to 2-4 using inorganic acid to obtain the adjusted high rare earth concentration molecular sieve double cross-linked filtrate.
[0026] (B3) The filtrate after the synthesis and filtration of NaY molecular sieve, the filtrate after the molecular sieve ultra-stable modification after pH adjustment, the filtrate of high rare earth concentration molecular sieve double crosslinking after pH adjustment, and the aluminum source are mixed and reacted. The pH is controlled at 9-11, the reaction temperature is controlled at 30-90℃, and the reaction time is 1-24h; the slurry after reaction is obtained.
[0027] (B4) The slurry after the reaction is filtered, washed with a washing solution with a pH value greater than 7, and filtered again to obtain rare earth composite active mesoporous and macroporous materials.
[0028] According to any of the above technical solutions, the acid can be one or more of hydrochloric acid, sulfuric acid, nitric acid, and phosphoric acid.
[0029] According to any of the above technical solutions, the washing solution is a washing solution containing ammonium ions, such as ammonia water or a solution containing one or more of ammonium sulfate, ammonium chloride, ammonium carbonate, or ammonium nitrate. The pH value of the washing solution is greater than 7, for example, pH value of 7.5-11. The concentration of the washing solution can be 1-10% by weight.
[0030] According to any of the above technical solutions, the washing solution can be a solution containing one or more of ammonium sulfate, ammonium chloride, ammonium carbonate, or ammonium nitrate, and the pH value of the washing solution can be adjusted to be greater than 7, for example, a pH value of 7.5-11. The concentration of ammonium salt in the washing solution containing one or more of ammonium sulfate, ammonium chloride, ammonium carbonate, or ammonium nitrate can be 1-10% by weight.
[0031] After contact exchange with a washing solution, washing can be optionally performed, for example, washing with water to remove acid radicals from the pores of the material.
[0032] In another aspect, the present invention provides a rare earth composite active mesoporous material, wherein, based on dry weight, the rare earth composite active mesoporous material contains 0.5-5% by weight of Na2O, 20-45% by weight of Al2O3, 30-65% by weight of SiO2 and 2-20% by weight of RE2O3.
[0033] Preferably, the specific surface area of the rare earth-containing composite active mesoporous material is 150–350 m². 2 / g.
[0034] Preferably, the nitrogen adsorption capacity method is used to measure the proportion of mesopores larger than 10 nm (the proportion of pore volume larger than 10 nm to the total pore volume) in the rare earth-containing composite active mesoporous material is more than 40%; the total pore volume is the pore volume of pores with a diameter greater than 0-100 nm, and the mesopores and macropores are pores with a diameter of 10-100 nm. The pore size distribution is calculated by the BJH method.
[0035] The rare earth-containing composite active mesoporous and macroporous materials are prepared according to the method described in any of the above technical solutions, which utilizes molecular sieve synthesis filtrate to synthesize rare earth-containing composite active mesoporous and macroporous materials.
[0036] In another aspect, the present invention provides a catalytic cracking catalyst, wherein, based on the dry weight of the catalytic cracking catalyst, the catalytic cracking catalyst contains 10-35% by weight of Y-type molecular sieve, 10-50% by weight of clay, 10-40% by weight of binder, and 10-30% by weight of the above-mentioned rare earth-containing composite active mesoporous and macroporous materials.
[0037] In another aspect, the present invention provides a method for preparing a catalytic cracking catalyst, comprising:
[0038] (S1) The binder, active components, clay, and the rare earth-containing composite active mesoporous and macroporous material or the rare earth-containing composite active mesoporous and macroporous material obtained by the method of synthesizing rare earth-containing composite active mesoporous and macroporous material using molecular sieve synthesis filtrate as described in any of the above technical solutions are mixed and pulped to form a slurry, which is then spray-dried to obtain microspheres.
[0039] (S2) The microspheres are calcined at 550-700°C, and optionally washed and dried to obtain a catalytic cracking catalyst.
[0040] According to the above-described method for preparing catalytic cracking catalyst, in one embodiment, the active component includes a Y-type molecular sieve, wherein the Y-type molecular sieve is selected from one or more of ultrastable Y-type molecular sieves, Y-type molecular sieves containing phosphorus and / or rare earth metals, and ultrastable Y-type molecular sieves containing phosphorus and / or rare earth metals; the clay is selected from one or more of kaolin, rettoitite, diatomaceous earth, montmorillonite, bentonite, and sepiolite; and the binder is selected from one or more of alumina sol, silica sol, silica-alumina composite sol, aluminum phosphate sol, and acidified pseudoboehmite.
[0041] In another aspect, the present invention provides an application of the catalytic cracking catalyst of the present invention in the catalytic cracking of heavy oil.
[0042] In another aspect, the present invention provides a catalytic cracking method, comprising the step of contacting a hydrocarbon oil with the catalytic cracking catalyst provided by the present invention or a catalytic cracking catalyst prepared by the method provided by the present invention. The hydrocarbon oil is, for example, heavy oil.
[0043] Optionally, the reaction conditions for the catalytic cracking include: a reaction temperature of 490–530°C and a catalyst-to-oil weight ratio of 3–8.
[0044] The present invention provides a method for synthesizing rare earth-containing composite active mesoporous and macroporous materials using molecular sieve synthesis filtrate. This method yields mesoporous and macroporous silica-alumina materials with excellent performance. These materials contain rare earth elements and exhibit high hydrothermal stability. The method also allows for the utilization of the NaY mother liquor, reducing the generation of sludge.
[0045] The catalytic cracking catalyst provided by this invention has good heavy oil cracking capability, high light oil yield, and can achieve high total liquid yield with a precursor that improves gasoline yield.
[0046] Other features and advantages of the present invention will be described in detail in the following detailed description section.
[0047] In this invention, the dry basis refers to the solid product of the substance, the filtrate or dispersion after drying and calcination at 850°C for 1 hour. Detailed Implementation
[0048] The following provides a detailed description of specific embodiments of the present invention. It should be understood that the specific embodiments described herein are for illustrative and explanatory purposes only and are not intended to limit the scope of the invention.
[0049] Example
[0050] The present invention will be further illustrated by the following examples, but the present invention is not limited thereto.
[0051] The raw materials used in the examples and comparative examples are as follows: the molecular sieve washing filtrate after hydrothermal ultrastabilization (first dispersion) was from Sinopec Catalyst Co., Ltd., with a dry basis content of 23.6 g / L, containing 3.3 wt% Na2O, 43.2 wt% Al2O3, 45.1 wt% SiO2, and 5.2 wt% RE2O3 based on dry basis weight;
[0052] The second dispersion (second cross-linked filtrate) used in the production of REY molecular sieves comes from Sinopec Catalyst Co., Ltd., with a dry basis content of 10 g / L. Based on dry basis weight, it contains 1.1 wt% Na2O, 8.8 wt% Al2O3, 31.2 wt% SiO2, and 50.1 wt% RE2O3.
[0053] The filtrate after filtration of NaY molecular sieve synthesis has a free SiO2 concentration of 40 g / L and a suspended solids concentration of 13.7 g / L. The dry basis composition of the suspended solids is 14.5 wt% Na2O, 3.1 wt% Al2O3, and 78.1 wt% SiO2, provided by Sinopec Catalyst Co., Ltd.
[0054] Rare earth ultrastable Y molecular sieve REY slurry: solid content 30% by weight, cell constant is Based on dry weight, the percentage content of Na2O is 1.6% and the content of RE2O3 is 17.9%.
[0055] Ultrastable Y molecular sieve USY slurry: solid content 30% by weight, cell constant is The percentage content based on dry weight is 1.3% for Na2O and 2.0% for RE2O3.
[0056] Both REY and USY, rare earth ultrastable Y molecular sieves, are produced by Sinopec Catalyst Co., Ltd.
[0057] Kaolin was produced by Suzhou Kaolin Company and has a solid content of 72% by weight.
[0058] The pseudoboehmite was produced by Shandong Aluminum Plant, with a solid content of 62.0% by weight.
[0059] The aluminum sol contains 21.5% by weight of alumina and was produced by Sinopec Catalyst Qilu Branch.
[0060] The hydrochloric acid was produced by Beijing Chemical Plant, and its specification was analytical grade with a mass concentration of 36%.
[0061] Aluminum sulfate solution: concentration 90g Al2O3 / L, produced by Sinopec Catalyst Co., Ltd.
[0062] The method for measuring suspended solids in filtrate is GB11901.
[0063] The method for measuring free silica is: GB / T 12149
[0064] The specific surface area was analyzed using the NB / SH / T 0959-2017 method, and the pore size distribution was analyzed using the BJH method based on the adsorption data obtained under these conditions.
[0065] The composition of the samples was determined by X-ray fluorescence spectroscopy (XRF).
[0066] The apparent bulk density of catalytic cracking catalysts was determined according to NB / SH / T 0954-2017.
[0067] The pore volume of catalytic cracking catalyst was determined using the water droplet method according to NB / SH / T 0955-2017.
[0068] The wear index of catalytic cracking catalyst was determined using NB / SH / T 0964-2017.
[0069] Example 1 of preparation of composite silicon-aluminum material
[0070] (1) The pH of the molecular sieve washing filtrate after hydrothermal ultrastability was adjusted to 2.9 using hydrochloric acid (20% by weight).
[0071] (2) The pH of the double crosslinking filtrate used in the production of REY molecular sieves was adjusted to 3.3 using hydrochloric acid (20% by weight).
[0072] (3) The above-mentioned pH-adjusted hydrothermally stabilized molecular sieve washing filtrate, NaY molecular sieve synthesis filtrate, the above-mentioned pH-adjusted REY molecular sieve production double crosslinking filtrate and aluminum sulfate solution were mixed in a volume ratio of 4:2:11:0.4. First, the NaY synthesis filtrate was added to the stirred tank, and then the above-mentioned pH-adjusted hydrothermally stabilized molecular sieve washing filtrate, the above-mentioned pH-adjusted REY molecular sieve production double crosslinking filtrate and aluminum sulfate solution were added to the stirred tank in parallel for mixing. The pH value of the mixture was 9.1, and the mixture was stirred at 50°C for 4 hours for hydrothermal reaction.
[0073] (4) The hydrothermal reaction solution was filtered, washed, and filtered again with a dilute ammonia solution at pH 9.7 to obtain RM-1, a rare earth-containing composite active mesoporous and macroporous material. The main weight percentage composition of RM-1 includes: Na₂O 4.4%, Al₂O₃ 22.3%, SiO₂ 46.6%, RE₂O₃ 16.4%, Cl 2.3%, SO₃ 4.6%, and a BET specific surface area of 253.3 m². 2 / g, the proportion of mesopores and macropores with a diameter greater than 10nm is 75.8% (the pore volume of mesopores and macropores with a diameter greater than 10nm and less than or equal to 100nm accounts for the total pore volume (pore volume with a diameter greater than 0 and less than or equal to 100nm)).
[0074] Example 2 of preparation of composite silicon-aluminum materials
[0075] (1) The pH of the molecular sieve washing filtrate after hydrothermal ultrastability was adjusted to 3.1 using hydrochloric acid (20% by weight).
[0076] (2) The pH of the double crosslinked filtrate used in the production of REY molecular sieves was adjusted to 3.3 using hydrochloric acid (concentration 20% by weight).
[0077] (3) The above-mentioned hydrothermal ultra-stable molecular sieve washing filtrate after pH adjustment, NaY molecular sieve synthesis filtrate, the above-mentioned pH-adjusted REY molecular sieve production double crosslinking filtrate and acidified pseudoboehmite slurry (Al2O3 content 3 wt%, pH 1.7, hydrochloric acid acidified) are mixed in a volume ratio of 6:3:5:1. First, the NaY molecular sieve filtrate is added to the stirred tank, and then the remaining liquid is added to the stirred tank in parallel flow according to the ratio for mixing. The pH is 10.0, and then the reaction is carried out at 60℃ for 4 hours.
[0078] (4) The reaction solution obtained in step (3) was filtered, washed and filtered again with a dilute ammonia solution at pH 10.5 to obtain the composite active mesoporous and macroporous material RM-2. The main components of the composite active mesoporous and macroporous material RM-2, by weight percentage, are as follows: Na2O 3.8, Al2O3 31.8, SiO2 49.2, RE2O3 6.7, Cl 2.4, SO3 3.9, and BET specific surface area 271.4 m². 2 / g, the proportion of mesopores and macropores larger than 10nm is 59.7%.
[0079] Example 3 of preparation of composite silicon-aluminum materials
[0080] (1) The pH of the molecular sieve washing filtrate after hydrothermal ultrastability was adjusted to 2.9 using hydrochloric acid (20% by weight).
[0081] (2) The pH of the double crosslinked filtrate used in the production of REY molecular sieves was adjusted to 2.8 using hydrochloric acid (concentration 20% by weight).
[0082] (3) The above-mentioned hydrothermally stabilized molecular sieve washing filtrate after pH adjustment, NaY molecular sieve synthesis filtrate, the above-mentioned pH-adjusted REY molecular sieve production double crosslinking filtrate and acidified pseudoboehmite slurry (Al2O3 content 3 wt%, pH value 2.5, hydrochloric acid acidified) are mixed in a volume ratio of 6:6:3:6. First, the NaY molecular sieve filtrate is added to the stirred tank, and then the remaining liquid is added to the stirred tank in parallel flow according to the ratio for mixing. The pH is 10.8, and the hydrothermal reaction is carried out at 60℃ for 4 hours.
[0083] (4) The hydrothermal reaction solution was filtered, washed, and filtered again with a dilute ammonia solution at pH 10.5 to obtain the composite active mesoporous and macroporous material RM-3. The main components of RM-3, by weight percentage, are: Na2O 4.5, Al2O3 52.4, SiO2 29.6, RE2O3 2.1, Cl 2.7, SO3 3.6, and BET specific surface area 290.1 m². 2 / g, the proportion of mesopores and macropores larger than 10nm is 46.9%.
[0084] Example 4 of preparation of composite silicon-aluminum materials
[0085] (1) The pH of the molecular sieve washing filtrate after hydrothermal ultrastability was adjusted to 2.5 using hydrochloric acid (20% by weight).
[0086] (2) The pH of the double crosslinked filtrate used in the production of REY molecular sieves was adjusted to 2.8 using hydrochloric acid (concentration 20% by weight).
[0087] (3) The above-mentioned hydrothermal ultra-stable molecular sieve washing filtrate after pH adjustment, NaY molecular sieve synthesis filtrate, the above-mentioned pH-adjusted REY molecular sieve production double crosslinking filtrate and acidified pseudoboehmite slurry (Al2O3 content 3 wt%, pH value 2.1, hydrochloric acid acidified) are mixed in a volume ratio of 4:5:3:2. First, the NaY molecular sieve filtrate is added to the stirred tank, and then the remaining liquid is added to the stirred tank in parallel flow according to the ratio for mixing. The pH is 9.5, and the hydrothermal reaction is carried out at 60℃ for 4 hours.
[0088] (4) The hydrothermal reaction solution was filtered, washed, and filtered again with a dilute ammonia solution at pH 10.5 to obtain the composite active mesoporous and macroporous material RM-4. The main components of the composite active mesoporous and macroporous material RM-4, by weight percentage, are as follows: Na2O 3.6 wt%, Al2O3 35.9 wt%, SiO2 48.2 wt%, RE2O3 3.2 wt%, Cl 2.9%, SO3 4.2%, and BET specific surface area 275.3 m². 2 / g, the proportion of mesopores and macropores larger than 10nm is 51.2%.
[0089] Comparative Example 1 for the preparation of composite materials
[0090] (1) The washing filtrate of hydrothermally stabilized molecular sieve, the filtrate after synthesis of NaY molecular sieve, the filtrate from the production of REY molecular sieve, and aluminum sulfate were mixed in a volume ratio of 4:2:11:0.4. First, the filtrate after synthesis of NaY molecular sieve was added to the stirred tank, and then the washing filtrate of hydrothermally stabilized molecular sieve, the filtrate from the production of REY molecular sieve, and aluminum sulfate were added to the stirred tank for mixing. The pH value of the mixture was 11.9, and the mixture was hydrothermally reacted at 50℃ for 4 hours. (2) The hydrothermally reacted liquid was filtered and washed and filtered with a dilute ammonia solution with pH 10.5 to obtain composite material DBM-1, whose composition includes: Na2O 4.3, Al2O3 22.2, SiO2 45.7, RE2O3 16.9, Cl 2.4, SO3 4.9; BET specific surface area: 156.6m². 2 / g, the proportion of mesopores and macropores larger than 10nm is 14.9%.
[0091] Comparative Example 2 of Composite Material Preparation
[0092] (1) The pH of the molecular sieve washing filtrate after hydrothermal ultrastability was adjusted to 1.2 using hydrochloric acid (concentration 20wt%);
[0093] (2) Adjust the pH of the double crosslinked filtrate in the production of REY molecular sieves to 1.3 using hydrochloric acid (concentration 20wt%);
[0094] (3) The filtrate after the synthesis and filtration of NaY molecular sieve, the washing filtrate of the molecular sieve after pH adjustment and hydrothermal superstability, the double crosslinking filtrate of REY molecular sieve production after pH adjustment and the acidified pseudoboehmite slurry (3% Al2O3 content, pH 1.7, acidified with hydrochloric acid) are added to the stirred tank in a volume ratio of 6:3:5:1 and mixed. The pH value is 1.5, and the mixture is hydrothermally reacted at 60℃ for 4 hours.
[0095] (4) After the above hydrothermal reaction, the liquid was filtered, and then exchanged, rinsed, washed, and filtered again using a dilute ammonia solution with a pH of 10.5 to obtain the composite material DBM-2. Its composition includes:
[0096] The specific surface area of Na₂O is 3.1, that of Al₂O₃ is 29.1, that of SiO₂ is 50.6, that of RE₂O₃ is 6.5, that of Cl is 4.4, that of SO₃ is 3.1, and that of BET is 221.1 m². 2 / g, the proportion of mesopores and macropores larger than 10nm is 21.2%.
[0097] Comparative Example 3 of Composite Material Preparation
[0098] Following the method of Example 2 for preparing composite materials, the only difference was that the silicon-aluminum material was prepared by sedimentation, centrifugation, and washing with a hydrothermally stabilized molecular sieve washing solution, followed by impregnation with rare earth elements to ensure the rare earth content was the same as in Example 2. The resulting composite material, DBM-3, contained 2.1 wt% Na₂O, 40.1 wt% Al₂O₃, 41.2 wt% SiO₂, 6.4 wt% RE₂O₃, 2.1 wt% Cl, 3.2 wt% SO₃, and a BET specific surface area of 151.4 m². 2 / g, the proportion of mesopores and macropores larger than 10nm is 9.7%.
[0099] Catalyst Preparation Example 1
[0100] A slurry with a solid content of 20% by weight was prepared by pulping composite silicon-aluminum materials.
[0101] 2.16 kg of kaolin, 1.86 kg of alumina sol, 1.61 kg of pseudoboehmite, and 2.95 kg of decationized water were added to a pulping tank and pulped for 60 minutes. Hydrochloric acid was added to adjust the pH to 3.0, and stirring was continued for another 60 minutes to obtain the first slurry. Then, 3.75 g of composite active mesoporous and macroporous material RM-1 slurry, 3.5 kg of REY slurry, and 0.83 kg of USY molecular sieve slurry were added and stirred for 60 minutes. The resulting slurry was spray-dried and calcined at 550 °C for 2 hours. It was washed twice, with each wash using a 0.3 wt% ammonium sulfate aqueous solution at 60 °C at a water:catalyst ratio of 10:1 (by weight). After drying, the catalytic cracking catalyst C1 provided by this invention was obtained, and its formulation and properties are shown in Table 1.
[0102] Catalyst Preparation Examples 2-5
[0103] The same method as in Catalyst Preparation Example 1 was used, except that Catalyst Preparation Examples 2, 3, 4, and 5 were prepared using different amounts of composite active mesoporous and macroporous materials RM-1 or RM-2, RM-3, and RM-4, respectively, denoted as C2, C3, C4, and C5. Their formulations and properties are shown in Table 1.
[0104] Table 1
[0105]
[0106] Table 1 shows the weight ratios, calculated on a dry basis.
[0107] Catalyst preparation comparative examples 1-3
[0108] The preparation methods for DB-1 and DB-2 to DB-3 are the same as those in Examples 1 and 3, respectively. The difference is that DBM-1 is used instead of RM-1, and DBM-2 and DBM-3 are used instead of RM-2 for catalyst preparation. The formulations and properties are shown in Table 1.
[0109] Catalyst preparation Comparative Example 4
[0110] 2.16 kg of kaolin, 1.86 kg of alumina sol, 1.61 kg of pseudoboehmite, and 5.66 kg of decationized water were added to a pulping tank and pulped for 60 minutes. Hydrochloric acid was added to adjust the pH to 3.0, and stirring was continued for another 60 minutes to obtain the first slurry. Then, 3.5 kg of REY and 0.83 kg of USY molecular sieve slurry were added, and the mixture was homogenized and stirred for 60 minutes. The resulting slurry was spray-dried and calcined at 550℃ for 2 hours. The mixture was washed twice, with each wash using a 0.3% by weight ammonium sulfate aqueous solution at 60℃, with a water:catalyst ratio of 10:1 (by weight). After drying, the comparative catalytic cracking catalyst DB-4 was obtained, with a pore volume of 0.3 mL / g, an apparent bulk density of 0.78 g / mL, and an attrition index of 0.7% / h.
[0111] The physicochemical performance evaluation results of the catalysts show that the catalysts C1 to C5 prepared using the silicon-aluminum materials RM-1, RM-2, RM-3, and RM-4 prepared in this invention can all achieve an attrition index of less than 2.5% / h, which is required for application. However, the catalysts prepared using silicon-aluminum materials DRM-1 to DRM-3 have a poor attrition index.
[0112] Catalysts C1-C5 and DB-1-4 were pre-aged at 800℃ with 100% steam for 17 hours in a fixed-bed aging unit, and then evaluated in a small fixed-bed reactor. The properties of the feedstock oil are shown in Table 2. The reaction temperature was 500℃, the catalyst-to-oil ratio (by weight) was 6, and the weight hourly space velocity was 8 h⁻¹. -1 .
[0113] Wherein, conversion rate = gasoline yield + liquefied petroleum gas yield + dry gas yield + coke yield;
[0114] Total liquid yield = LPG yield + gasoline yield + diesel yield;
[0115] Light oil yield = LPG yield + Gasoline yield
[0116] The evaluation results are shown in Table 3.
[0117] Table 2 Properties of Crude Oil
[0118]
[0119] Table 3 Evaluation Results
[0120]
[0121]
[0122] The results in Table 3 show that, compared with Comparative Examples 1-4, the catalysts C1-C5 containing rare earth composite active mesoporous materials prepared in Examples 1-5 of the present invention have significantly higher gasoline yields and lower heavy oil yields, indicating that the catalytic cracking catalysts containing rare earth composite active mesoporous materials provided by the present invention have strong heavy oil cracking capabilities.
[0123] It is evident that the rare earth-containing composite active mesoporous and macroporous materials obtained by the method of synthesizing rare earth composite active mesoporous and macroporous materials using molecular sieve synthesis filtrate provided by the present invention have good heavy oil cracking ability, and can improve gasoline yield when used in combination with Y molecular sieve.
[0124] The preferred embodiments of the present invention have been described in detail above. However, the present invention is not limited to the specific details in the above embodiments. Within the scope of the technical concept of the present invention, various simple modifications can be made to the technical solution of the present invention, and these simple modifications all fall within the protection scope of the present invention.
[0125] It should also be noted that the various specific technical features described in the above specific embodiments can be combined in any suitable manner without contradiction. In order to avoid unnecessary repetition, the present invention will not describe the various possible combinations separately.
[0126] Furthermore, various different embodiments of the present invention can be combined in any way, as long as they do not violate the spirit of the present invention, they should also be regarded as the content disclosed by the present invention.
Claims
1. A method for synthesizing rare earth-containing composite active mesoporous and macroporous materials using molecular sieve synthesis filtrate, comprising the following steps: (1) The filtrate after the synthesis and filtration of NaY molecular sieve is mixed with the first dispersion, the second dispersion and the aluminum source, and the pH value of the mixture is controlled to be 9-11. The reaction is carried out at a reaction temperature of 30-90℃ for 1-24 hours. The first dispersion has a solid content of 0.5-2 wt% and a pH value of 1-4. The dry basis chemical composition of the solid product obtained by drying the first dispersion includes 1-5 wt% Na2O, 35-50 wt% Al2O3, 40-55 wt% SiO2 and 2-8 wt% RE2O3. The second dispersion has a solid content of 0.1-2 wt% and a pH value of 2-4. The dry basis chemical composition of the solid product obtained by drying the second dispersion includes 0.5-2.5 wt% Na2O, 5-30 wt% Al2O3, 20-50 wt% SiO2 and 40-70 wt% RE2O. The first dispersion is the filtrate after the molecular sieve is modified to be ultrastable; the second dispersion is the filtrate of the high rare earth concentration molecular sieve with two crosslinking after adjustment; (B1) the filtrate after the molecular sieve is modified to be ultrastable after adjustment is obtained by adjusting the pH value of the filtrate after the molecular sieve is ultrastable after adjustment to 1-4 using inorganic acid; (B2) the filtrate of the high rare earth concentration molecular sieve with two crosslinking after adjustment is obtained by adjusting the pH value of the filtrate of the high rare earth concentration molecular sieve with two crosslinking to 2-4 using inorganic acid; The first and second dispersions are not added to the reaction vessel before the filtrate is added after the NaY molecular sieve synthesis and filtration. The first and second dispersions are synthesized and filtered using NaY molecular sieves, and the resulting filtrates are simultaneously added to the reaction vessel; or... First, the filtrate from the synthesis and filtration of NaY molecular sieve is added to the reactor. Then, the first dispersion, the second dispersion, and the aluminum source dispersion are added to the reactor in a parallel flow. Alternatively, The filtrate after the synthesis and filtration of NaY molecular sieve, the first dispersion, the second dispersion and the dispersion of the aluminum source are sequentially added to the stirred tank. The filtrate after the molecular sieve is modified with ultra-stable material is the filtrate obtained by washing after hydrothermal ultra-stable material and / or silicon tetrachloride ultra-stable material modification; the high rare earth concentration molecular sieve double-exchange filtrate is the filtrate obtained by secondary exchange of modified Y-type molecular sieve with rare earth content higher than 15% by weight and exchange liquid with rare earth oxide content higher than 1% by weight. (2) Filtration, contact exchange with washing liquid with pH greater than 7, washing, filtration, to obtain rare earth composite active medium and macroporous material.
2. The method according to claim 1, characterized in that, The aluminum source is Al(NO3)3, AlCl3, or Al2(SO4). 3、 One or more of boehmite and alumina sol.
3. The method according to claim 1, characterized in that, The mixture formed by the filtrate after synthesis and filtration of the NaY molecular sieve, the first dispersion, the second dispersion, and the aluminum source has the following weight ratio: SiO 2： Al2O3 is 25~65: 20~50, RE2O 3： Al₂O₃ is 2~20: 20~50; Na₂O ： Al2O3 ratio is 0.5 ~ 5: 20 ~ 50.
4. The method according to claim 3, characterized in that, SiO₂ in the filtrate after NaY molecular sieve synthesis and filtration, the first dispersion, and the second dispersion. 2、 The total mass ratio of Al2O3 and RE2O3 to the mass ratio of Al2O3 in the aluminum source is 1~20:
1. The solid content of the mixture formed by the filtrate, the first dispersion, the second dispersion and the aluminum source after the synthesis and filtration of the NaY molecular sieve is 0.5~10% by weight or 1.5~5% by weight.
5. The method according to any one of claims 1 to 4, characterized in that, The suspended solids concentration in the filtrate after the molecular sieve ultra-stable modification is 5000~15000 mg / L; the dry basis concentration in the high rare earth concentration molecular sieve double crosslinking filtrate is 3000~15000 mg / L.
6. The method according to claim 1, characterized in that, It also includes the following steps: (B3) The filtrate after the synthesis and filtration of NaY molecular sieve, the filtrate after the molecular sieve ultra-stable modification after pH adjustment, the filtrate of high rare earth concentration molecular sieve double crosslinking after pH adjustment, and the aluminum source are mixed and reacted. The pH is controlled at 9-11, the reaction temperature is controlled at 30-90℃, and the reaction time is 1-24h; the reaction slurry is obtained. (B4) The slurry after the reaction is filtered, washed with a washing solution with a pH value greater than 7, and filtered again to obtain rare earth composite active mesoporous and macroporous materials.
7. The method according to claim 1, characterized in that, The inorganic acid is one or more of hydrochloric acid, sulfuric acid, nitric acid, and phosphoric acid; the washing solution is a washing solution containing ammonium ions, and the pH value of the washing solution is greater than 7.
8. The method according to claim 7, characterized in that, The pH value of the washing solution is 7.5-11.
9. A rare earth-containing composite active mesoporous and macroporous material, wherein, Based on the dry weight of the rare earth-containing composite active mesoporous material, the rare earth-containing composite active mesoporous material contains 0.5-5% by weight Na₂O, 20-45% by weight Al₂O₃, 30-65% by weight SiO₂, and 2-20% by weight RE₂O₃; the specific surface area of the rare earth-containing composite active mesoporous material is 150-350 m². 2 / g; measured by nitrogen adsorption capacity method, the proportion of mesopores larger than 10nm in the rare earth-containing composite active mesoporous material is more than 40%; the total pore volume is the pore volume of pores with a pore size greater than 0 and not exceeding 100nm, and the mesopores and macropores are pores with a pore size of 10-100nm, and the pore size distribution is calculated by BJH method; the rare earth-containing composite active mesoporous material is prepared according to the method described in any one of claims 1-8.
10. A catalytic cracking catalyst, based on the dry weight of the catalytic cracking catalyst, wherein the catalytic cracking catalyst contains 10-35% by weight of Y-type molecular sieve, 10-50% by weight of clay, 10-40% by weight of binder, and 10-30% by weight of rare earth-containing composite active mesoporous or macroporous material obtained according to any one of claims 1-8 or the rare earth-containing composite active mesoporous or macroporous material according to claim 9.
11. A method for preparing a catalytic cracking catalyst, comprising: (S1) Mix the binder, active component, clay and rare earth-containing composite active medium and macroporous material as described in claim 10 or rare earth-containing composite active medium and macroporous material obtained in any one of claims 1-8 to form a slurry, and spray dry to obtain microspheres; (S2) The microspheres are calcined at 550-700°C, washed and dried or not washed and not dried to obtain a catalytic cracking catalyst.
12. The method according to claim 11, wherein, The active component includes Y-type molecular sieves; the clay is selected from one or more of kaolin, rettoitite, diatomaceous earth, montmorillonite, bentonite, and sepiolite; the binder is selected from one or more of alumina sol, silica sol, silica-alumina composite sol, aluminum phosphate sol, and acidified pseudoboehmite.
13. The method according to claim 12, wherein, The Y-type molecular sieve is an ultrastable Y-type molecular sieve containing phosphorus and / or rare earth metals.
14. The method according to claim 12, wherein, The Y-type molecular sieve is a Y-type molecular sieve containing phosphorus and / or rare earth metals.
15. The method according to claim 12, wherein, The Y-type molecular sieve is an ultrastable Y-type molecular sieve.
16. A catalytic cracking method, comprising the step of contacting heavy oil with the catalytic cracking catalyst of claim 10 or the catalytic cracking catalyst prepared by any one of claims 11 to 15.