Catalytic reaction rectification element as well as preparation method and application thereof
By using the prepared catalytic reactive distillation element in a catalytic reactive distillation column, the problem of low catalyst efficiency was solved, and the preparation of high-purity acid anhydrides with high conversion rate was achieved, while reducing production costs and energy consumption.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2025-12-16
- Publication Date
- 2026-04-10
AI Technical Summary
The catalysts in existing catalytic reactive distillation columns have low efficiency and are difficult to match with the distillation process, resulting in difficulty in improving product purity. They also suffer from low raw material utilization and separation difficulties.
A catalytic reactive distillation element is prepared by hydrothermal reaction of silicon source, aluminum source, template agent and metal salt on catalytic reactive distillation packing to form molecular sieve supported packing, and then by bimetallic modification, thus preparing a catalytic reactive distillation element that combines catalysis and distillation, which is then applied in a catalytic reactive distillation column.
This method enables the preparation of high-purity acid anhydride products, improves reaction conversion rate and selectivity, reduces raw material consumption and energy consumption, simplifies the process flow, and extends the service life of catalysts.
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Abstract
Description
TECHNICAL FIELD
[0001] The present application relates to the preparation of fine chemical products, in particular to a catalytic reaction rectification element and a preparation method and application thereof. BACKGROUND
[0002] Aliphatic carboxylic anhydride is an important class of organic compounds, especially organic carboxylic anhydride with carbon number of 3-9, such as propionic anhydride, n-butyric anhydride, isobutyric anhydride, n-valeric anhydride, iso-valeric anhydride, n-hexanoic anhydride, n-heptanoic anhydride, iso-octanoic anhydride, iso-nonyl anhydride, etc., which are widely used in the fields of ester synthesis, organic synthesis intermediates, coatings, food, medicine, etc.
[0003] The traditional synthesis technology of carboxylic anhydride includes co-heating method of acyl chloride and carboxylic acid salt, dehydration method of carboxylic acid and sulfur dichloride, synthesis method of carboxylic acid and enone, etc. These processes have problems such as expensive raw materials or difficult source, difficult treatment of by-products, serious three wastes, low yield and poor economic benefit.
[0004] The industrialized and mature preparation method of organic carboxylic anhydride with carbon number of 3-9 is to prepare it by anhydride exchange reaction of organic carboxylic acid with carbon number of 3-9 and other carboxylic anhydride with different carbon number. The specific reaction mechanism is as follows:
[0005]
[0006] The reaction first generates intermediate product R1, R2 mixed anhydride, which is an irreversible reaction; R1, R2 mixed anhydride further reacts with R1 carboxylic acid to generate R1 anhydride and R2 carboxylic acid, which is a slow and reversible reaction. The main problems of this method are: (1) the reaction exists mixed anhydride intermediate, which is difficult to completely convert, often needs to increase the amount of R1 carboxylic acid to improve the conversion rate of mixed anhydride, which makes the utilization rate of raw materials low or increases the energy consumption of separation; (2) due to the reversibility of the reaction, it is difficult to obtain high conversion rate for batch process, and the operation difficulty will be increased if product refining or material recycling is involved; (3) the boiling point of mixed anhydride is close to that of target product anhydride, which makes it difficult to separate them, and it is difficult to obtain high-purity (such as >99.5%) anhydride product.
[0007] The catalytic reaction rectification process is a coupling technology that integrates catalytic reaction and rectification separation in the same equipment (catalytic rectification column), and the core is to complete the conversion of reactants and the separation of products / reactants in the column at the same time, so as to promote the forward reaction of reversible reaction.
[0008] However, the catalytic reaction rectification column is a highly complex system, and the key is the synthesis of catalyst and the efficient coupling of catalytic reaction and rectification process. At present, there are still problems such as low efficiency of catalyst, difficulty in matching catalyst with rectification process, etc., which makes it difficult to effectively improve the purity of product, so there are few reports on the use of catalytic reaction rectification for anhydride exchange reaction to prepare anhydride. SUMMARY
[0009] Based on this, the application provides a catalytic reaction rectification element, a preparation method and application thereof. The catalytic reaction rectification element is used for catalytic reaction rectification, and high-purity acid anhydride products can be prepared.
[0010] In a first aspect, the application provides a preparation method of a catalytic reaction rectification element, comprising the following steps:
[0011] mixing a silicon source, an aluminum source, a template agent and first water to prepare a first solution;
[0012] mixing a coupling agent, a first metal salt, a second metal salt and second water to prepare a second solution; the metal element in the first metal salt comprises cobalt or copper, and the metal element in the second metal salt comprises a rare earth element in the lanthanide series;
[0013] placing the catalytic reaction rectification packing in the first solution to perform a first hydrothermal reaction, and then drying to prepare a molecular sieve loaded packing;
[0014] placing the molecular sieve loaded packing in the second solution to perform a second hydrothermal reaction to prepare the catalytic reaction rectification element.
[0015] In one of the embodiments, the catalytic reaction rectification packing has one or more of the following characteristics:
[0016] (1) the specifications include one or more of Raschig rings, Pall rings and theta rings;
[0017] (2) the size is 2-8 mm;
[0018] (3) the material includes one or more of ceramic, stainless steel and titanium alloy.
[0019] In one of the embodiments, the conditions for preparing the molecular sieve loaded packing include:
[0020] (1) the silicon source includes one or more of silica sol, fumed silica, tetraethyl orthosilicate and di-tert-butylsilane;
[0021] (2) the aluminum source includes one or more of aluminum isopropoxide, pseudo-boehmite and aluminum sulfate;
[0022] (3) the template agent includes one or more of ethyl tri-n-propyl ammonium iodide, diethyl propyl ammonium iodide and triisooctylamine;
[0023] (4) in the first solution, the mass ratio of the silicon source, the aluminum source and the template agent is 1:(0.02-1):(0.01-0.5);
[0024] (5) the first water is added in an amount of 10 times to 100 times of the total mass of the silicon source, the aluminum source and the template agent;
[0025] (6) the mass percentage of the catalytic reaction rectification filler is 1% to 50% based on the mass of the first solution;
[0026] (7) the temperature of the first hydrothermal reaction is 100°C to 160°C, and the time of the first hydrothermal reaction is 20h to 50h;
[0027] (8) the temperature of the drying is 100°C to 130°C, and the time of the drying is 20h to 40h.
[0028] In one of the embodiments, the conditions for preparing the catalytic reaction rectification element include:
[0029] (1) the coupling agent includes one or more of silane coupling agent and titanate coupling agent;
[0030] Optionally, the silane coupling agent includes one or both of KH-151 and KH-561;
[0031] Optionally, the titanate coupling agent includes one or more of n-titanium tetrakis octylate, n-titanium tetrakis ethylate and n-titanium tetrakis butylate;
[0032] (2) in the second metal salt, the lanthanide series element includes lanthanum, samarium or praseodymium;
[0033] (3) the mass ratio of the first metal salt to the second metal salt is 0.5 to 5:1;
[0034] (4) the first metal salt and the second metal salt are each independently phosphate, chloride, nitrate or sulfate;
[0035] (5) the second water is added in an amount of 2 times to 20 times of the total mass of the first metal salt and the second metal salt;
[0036] (6) the coupling agent is added in an amount of 1% to 50% of the total mass of the first metal salt and the second metal salt;
[0037] (7) the mass percentage of the molecular sieve loading filler is 1% to 50% based on the mass of the second solution;
[0038] (8) the second hydrothermal reaction is carried out under the assistance of microwave, and optionally, the frequency of the microwave is 500MHz to 1000MHz;
[0039] (9) the temperature of the second hydrothermal reaction is 100°C to 130°C, and the time of the second hydrothermal reaction is 10h to 30h.
[0040] In a second aspect of the present application, the catalytic reaction rectification element prepared by the preparation method of the first aspect is provided.
[0041] In a third aspect of the present application, the catalytic reaction rectification element of the second aspect is applied in an acid anhydride exchange reaction.
[0042] In a fourth aspect of the present application, a catalytic reaction rectification device is provided, which comprises a rectification section, a catalytic reaction section and a stripping section connected in sequence, and the catalytic reaction section is filled with the catalytic reaction rectification element of the second aspect.
[0043] Optionally, the rectification section and the stripping section are filled with catalytic reaction rectification packing; further optionally, the catalytic reaction rectification packing filled in the rectification section and the stripping section each independently comprises one or more of a Raschig ring, a Pall ring, a theta ring, a hole-plate corrugated packing and a wire mesh corrugated packing.
[0044] In a fifth aspect of the present application, a catalytic reaction rectification preparation method of an acid anhydride is provided, which adopts the catalytic reaction rectification element of the second aspect or the catalytic reaction rectification device of the fourth aspect to perform catalytic reaction rectification.
[0045] Optionally, the catalytic reaction rectification is performed by using the catalytic reaction rectification device of the third aspect, which comprises the following steps:
[0046] The raw material carboxylic acid and the raw material acid anhydride are continuously injected into the catalytic reaction section to perform an acid anhydride exchange reaction, and the by-product carboxylic acid and the product acid anhydride are continuously collected from the top of the rectification section and the side line of the stripping section.
[0047] In one of the embodiments, the raw material acid anhydride and the product acid anhydride have different carbon numbers.
[0048] Optionally, the raw material carboxylic acid comprises an organic carboxylic acid with a carbon number of 3-9, which optionally comprises one or more of propionic acid, n-butyric acid, isobutyric acid, n-valeric acid, isovaleric acid, n-hexanoic acid, n-heptanoic acid, iso-octanoic acid and iso-nonyl acid.
[0049] Optionally, the raw material acid anhydride comprises an organic carboxylic acid anhydride with a carbon number of 2-4, which optionally comprises one or more of acetic anhydride, propionic anhydride, n-butyric anhydride and isobutyric anhydride.
[0050] Optionally, the product acid anhydride comprises an organic carboxylic acid anhydride with a carbon number of 3-9, which optionally comprises one or more of propionic anhydride, n-butyric anhydride, isobutyric anhydride, n-valeric anhydride, isovaleric anhydride, n-hexanoic anhydride, n-heptanoic anhydride, iso-octanoic anhydride and iso-nonyl anhydride.
[0051] In one of the embodiments, the catalytic reaction rectification preparation method of the acid anhydride has one or more of the following characteristics:
[0052] (1) The total mass hourly space velocity (MHSV) of the feedstock carboxylic acid and the feedstock anhydride is 0.2 h⁻¹. -1 ~1h -1 ;
[0053] (2) The feed molar ratio of the raw material carboxylic acid to the raw material anhydride is (2~5):1, and can be selected as (2~2.1):1;
[0054] (3) In the catalytic reaction distillation equipment, the theoretical number of plates in the distillation section is 3 to 10;
[0055] (4) In the catalytic reaction distillation equipment, the theoretical number of plates in the catalytic reaction section is 3 to 10;
[0056] (5) In the catalytic reaction distillation equipment, the theoretical number of trays in the stripping section is 3 to 10;
[0057] (6) The conditions for catalytic reactive distillation include: operating pressure of 5 kPaA ~ 30 kPaA, reflux ratio of (1 ~ 5):1, and temperature of 100℃ ~ 200℃.
[0058] The catalytic reactive distillation element prepared by the preparation method provided in this application can be applied to catalytic anhydride exchange reactions. It can also be adapted to catalytic reactive distillation technology to achieve efficient coupling of catalytic reaction and separation on the surface of the catalytic distillation element. High-purity product carboxylic anhydride can be obtained through catalytic anhydride exchange reaction. Moreover, the reaction has higher conversion rate and selectivity, less raw material consumption, large processing capacity, and low equipment cost and energy consumption.
[0059] Specifically, compared with traditional anhydride synthesis processes, this application has the following advantages:
[0060] (1) The catalytic reaction process is coupled with the distillation separation process. The catalyst promotes the rapid conversion of the heterohydric intermediates in the acid anhydride synthesis process into the product acid anhydride, and the acid anhydride is continuously separated by distillation, which promotes the chemical equilibrium to shift in the positive direction, improves the reaction yield, simplifies the process flow, and reduces the production cost.
[0061] (2) The catalytic distillation element is modified with bimetallic mesoporous molecular sieve, which has good catalytic activity. It can reduce the amount of packing or increase the amount of raw material processed, reduce the size of the reactive distillation column, reduce the feed ratio of raw carboxylic acid and raw anhydride, and make the conversion of anhydride intermediates more thorough, making it easier to obtain high-purity anhydride products.
[0062] Furthermore, the active components of this catalytic distillation element are grown in situ on the distillation packing support, which solves the problems of difficult packing and disassembly and poor gas-liquid mass transfer caused by packaging or binding the catalyst in the column in the existing reactive distillation process. It has a lower pressure drop and better gas-liquid mass transfer effect during use. After treatment with coupling agent, the active components and the support of this catalytic distillation element have stronger interaction forces and a longer service life. Detailed Implementation
[0063] The catalytic reactive distillation element, its preparation method, and its application are further described in detail below with reference to specific embodiments. This application can be implemented in many different forms and is not limited to the embodiments described herein. Rather, these embodiments are provided to provide a more thorough and complete understanding of the disclosure of this application.
[0064] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this application belongs. The terminology used herein is for the purpose of describing particular embodiments only and is not intended to be limiting of the application.
[0065] In this article, "one or more" refers to any one, two or more of the listed items.
[0066] In this application, terms such as "first aspect," "second aspect," "third aspect," and "fourth aspect" are used for descriptive purposes only and should not be construed as indicating or implying relative importance or quantity, nor should they be construed as implicitly indicating the importance or quantity of the indicated technical features. Moreover, terms such as "first," "second," "third," and "fourth" serve only as a non-exhaustive enumeration and should be understood not to constitute a closed limitation on quantity.
[0067] In this application, the technical features described in an open-ended manner include both closed technical solutions consisting of the listed features and open technical solutions that include the listed features.
[0068] In this application, numerical ranges are referred to as continuous unless otherwise specified, and include the minimum and maximum values of the range, as well as every value between the minimum and maximum values. Furthermore, when the range refers to integers, it includes every integer between the minimum and maximum values of the range. Additionally, when multiple ranges are provided to describe a feature or characteristic, the ranges may be merged. In other words, unless otherwise specified, all ranges disclosed herein should be understood to include any and all subranges to which they are incorporated.
[0069] Unless otherwise specified, the percentage content mentioned in this application refers to mass percentage for solid-liquid mixtures and solid-phase-solid mixtures, and volume percentage for liquid-phase-liquid mixtures.
[0070] Unless otherwise specified, all percentage concentrations mentioned in this application refer to the final concentration. The final concentration refers to the proportion of the added component in the system after the addition of that component.
[0071] Unless otherwise specified, the temperature parameters in this application may be either constant temperature processing or processing within a certain temperature range. The constant temperature processing allows for temperature fluctuations within the precision range controlled by the instrument.
[0072] In this application, room temperature generally refers to 4℃~30℃, and preferably 20±5℃.
[0073] Some embodiments of this application provide a method for preparing a catalytic reactive distillation element, comprising the following steps:
[0074] A first solution is prepared by mixing a silicon source, an aluminum source, a template agent, and a first water.
[0075] A second solution is prepared by mixing a coupling agent, a first metal salt, a second metal salt, and second water; the metal element in the first metal salt includes cobalt or copper, and the metal element in the second metal salt includes lanthanide rare earth elements.
[0076] The catalytic reactive distillation packing was placed in the first solution for a first hydrothermal reaction, and then dried to prepare the molecular sieve supported packing.
[0077] The molecular sieve-supported packing is placed in the second solution to carry out a second hydrothermal reaction to prepare the catalytic reaction distillation element.
[0078] Understandably, in the first hydrothermal reaction, mesoporous molecular sieves can be directly grown on catalytic reactive distillation packing material via hydrothermal crystallization. In the second hydrothermal reaction, the mesoporous molecular sieves can be bimetallic modified to prepare catalytic reactive distillation elements that combine catalysis and distillation.
[0079] In some embodiments, the catalytic reactive distillation packing material is configured to include one or more of Raschig rings, Pall rings, and θ rings.
[0080] In some embodiments, the size of the catalytic reactive distillation packing is 2-8 mm.
[0081] In some embodiments, the catalytic reactive distillation packing material includes one or more of ceramics, stainless steel, and titanium alloys.
[0082] Specifically, in the process of preparing molecular sieve supported packing materials:
[0083] In some embodiments, the silicon source includes one or more of silica sol, fumed silica, tetraethyl orthosilicate, and di-tert-butylsilane.
[0084] In some embodiments, the aluminum source includes one or more of aluminum isopropoxide, boehmite, and aluminum sulfate.
[0085] In some embodiments, the template agent includes one or more of ethyltri-n-propylammonium iodide, diethylpropylammonium iodide, and triisooctylamine.
[0086] In some embodiments, the mass ratio of the silicon source, the aluminum source, and the template agent in the first solution is 1:(0.02~1):(0.01~0.5). Specifically, this mass ratio includes, but is not limited to: 1:0.02:0.01, 1:0.02:0.5, 1:1:0.01, 1:1:0.5, 1:0.3:0.5, 1:1:0.02, 1:0.06:0.5, or any range between the foregoing.
[0087] In some embodiments, the amount of the first water added is 10 to 100 times the total mass of the silicon source, the aluminum source, and the template agent. Specifically, this multiple includes, but is not limited to, 10, 20, 30, 40, 50, 60, 70, 80, 90, 100 times, or any range between the foregoing.
[0088] In some embodiments, the mass percentage of the catalytic reactive distillation packing is 1% to 50% based on the mass of the first solution. Specifically, this mass percentage includes, but is not limited to: 1%, 5%, 10%, 15%, 20%, 25%, 30%, 35%, 40%, 45%, 50%, or any range between the foregoing.
[0089] Furthermore, properly controlling the conditions of the hydrothermal reaction can improve the interaction between the active components and the carrier, thus extending the service life.
[0090] In some embodiments, the temperature of the first hydrothermal reaction is 100°C to 160°C. Specifically, the temperature of the first hydrothermal reaction includes, but is not limited to, 100°C, 110°C, 120°C, 130°C, 140°C, 150°C, 160°C, or any range between the foregoing. Further, the temperature of the first hydrothermal reaction is 110°C to 160°C.
[0091] In some embodiments, the duration of the first hydrothermal reaction is 20 to 50 hours. Specifically, the duration of the first hydrothermal reaction includes, but is not limited to, 20 hours, 25 hours, 30 hours, 35 hours, 40 hours, 45 hours, 50 hours, or any range between the two mentioned above.
[0092] Understandably, the drying method may include removing the filler after the first hydrothermal reaction is completed, placing it in a hot air oven for drying after there is no obvious liquid retention on it, and solidifying the loaded molecular sieve during the drying process.
[0093] In some embodiments, the drying temperature is 100°C to 130°C. Specifically, the drying temperature includes, but is not limited to, 100°C, 150°C, 200°C, 250°C, 130°C, or any range between the two.
[0094] In some embodiments, the drying time is 20h to 40h. Specifically, the drying time includes, but is not limited to, 20h, 25h, 30h, 35h, 40h or any range between the two mentioned above.
[0095] Specifically, in the process of preparing catalytic reactive distillation elements:
[0096] In some embodiments, the coupling agent includes one or more of silane coupling agents and titanate coupling agents. Using a suitable type of coupling agent can improve the interaction between the active component and the support, thus extending its service life.
[0097] Without limitation, the silane coupling agent includes one or both of KH-151 and KH-561.
[0098] Without limitation, the titanate coupling agent includes one or more of tetraoctyl titanate, tetraethyl titanate, and tetrabutyl titanate.
[0099] Without limitation, in the second metal salt, the lanthanide rare earth element includes lanthanum, samarium, or praseodymium.
[0100] In some embodiments, the metal element in the first metal salt includes cobalt. Using a suitable type of metal element can further improve catalytic efficiency and yield product anhydrides with higher purity and yield.
[0101] In some embodiments, the mass ratio of the first metal salt to the second metal salt is (0.5~5):1. Specifically, this mass ratio includes, but is not limited to: 0.5:1, 2:3, 1:1, 1.5:1, 2:1, 2.5:1, 3:1, 3.5:1, 4:1, 4.5:1, 5:1, or any range between the two aforementioned.
[0102] Without limitation, the first metal salt and the second metal salt are each independently a phosphate, chloride, nitrate or sulfate.
[0103] In some embodiments, the amount of the second water added is 2 to 20 times the total mass of the first and second metal salts. Specifically, this multiple includes, but is not limited to, 2 times, 5 times, 10 times, 15 times, 20 times, or any range between the two aforementioned.
[0104] In some embodiments, the amount of coupling agent added is 1% to 50% of the total mass of the first metal salt and the second metal salt. Specifically, the amount added includes, but is not limited to: 1%, 5%, 10%, 15%, 20%, 25%, 30%, 35%, 40%, 45%, 50%, or any range between the foregoing.
[0105] In some embodiments, the molecular sieve-supported packing material accounts for 1% to 50% of the mass percentage of the second solution. Specifically, this mass percentage includes, but is not limited to, 1%, 5%, 10%, 15%, 20%, 25%, 30%, 35%, 40%, 45%, 50%, or any range between the foregoing.
[0106] In some embodiments, the second hydrothermal reaction is carried out with microwave assistance. Further, the microwave frequency is 500MHz to 1000MHz. Reasonable control of the microwave frequency can improve the interaction between the active component and the carrier, extending the service life. Specifically, the microwave frequency includes, but is not limited to: 500MHz, 550MHz, 600MHz, 650MHz, 700MHz, 750MHz, 800MHz, 850MHz, 900MHz, 950MHz, 1000MHz, or any range between the foregoing. Further, the microwave frequency is 500MHz to 800MHz.
[0107] In some embodiments, the temperature of the second hydrothermal reaction is 100°C to 130°C. Specifically, the temperature includes, but is not limited to: 100°C, 105°C, 110°C, 115°C, 120°C, 125°C, 130°C, or any range between the two mentioned above.
[0108] In some embodiments, the second hydrothermal reaction takes 10 to 30 hours. Specifically, this time includes, but is not limited to, 10 hours, 15 hours, 20 hours, 25 hours, 30 hours, or any range between the two mentioned above.
[0109] Without limitation, after the second hydrothermal reaction is completed, the process also includes washing and drying steps. Washing can be done with solvents such as ethanol, and drying can be done with methods such as vacuum drying.
[0110] In other embodiments of this application, catalytic reactive distillation elements prepared by the preparation method described above are provided.
[0111] Other embodiments of this application provide the application of the catalytic reactive distillation element described above in anhydride exchange reactions.
[0112] Other embodiments of this application provide a catalytic reactive distillation apparatus, comprising a distillation section, a catalytic reaction section, and a stripping section connected in sequence, wherein the catalytic reaction section is filled with catalytic reactive distillation elements as described above.
[0113] Understandably, catalytic reactive distillation equipment refers to a catalytic reactive distillation column, which includes, from the ground where the catalytic reactive distillation column is located, a stripping section, a catalytic reaction section, and a rectification section connected in sequence.
[0114] Understandably, the rectification section and the stripping section are also filled with catalytic reaction distillation packing.
[0115] In some embodiments, the catalytic reactive distillation packings filled in the rectification section and the stripping section each independently include one or more of Raschig rings, Pall rings, θ rings, perforated plate corrugated packings, and wire mesh corrugated packings.
[0116] Without limitation, the catalytic reactive distillation packing material filled in the rectification section and the stripping section may be the same or different; the catalytic reactive distillation packing material filled in the rectification section and the stripping section may be the same or different from the catalytic reactive distillation packing material in the catalytic reactive distillation element.
[0117] Other embodiments of this application provide a method for preparing acid anhydrides by catalytic reactive distillation, which uses the catalytic reactive distillation element or the catalytic reactive distillation equipment described above to perform the catalytic reactive distillation.
[0118] Furthermore, the catalytic reactive distillation using the catalytic reactive distillation equipment described above includes the following steps:
[0119] The raw material carboxylic acid and raw material anhydride are continuously injected into the catalytic reaction section to carry out anhydride exchange reaction, and the by-product carboxylic acid and product anhydride are continuously collected from the top of the rectification section and the side stream of the stripping section.
[0120] Without limitation, the raw material carboxylic acid and the raw material acid anhydride are injected from the upper and lower ends of the catalytic reaction section, respectively.
[0121] Understandably, the number of carbon atoms in the raw material anhydride is different from that in the product anhydride.
[0122] Without limitation, the raw material carboxylic acid includes organic carboxylic acids having 3 to 9 carbon atoms, and may include one or more of propionic acid, n-butyric acid, isobutyric acid, n-valeric acid, isovaleric acid, n-hexanoic acid, n-heptanoic acid, isooctanoic acid, and isononanoic acid.
[0123] Without limitation, the raw material anhydride includes organic carboxylic acid anhydrides with 2 to 4 carbon atoms, and may include one or more of acetic anhydride, propionic anhydride, n-butyric anhydride and isobutyric anhydride.
[0124] Without limitation, the product anhydride includes organic carboxylic acid anhydrides having 3 to 9 carbon atoms, optionally including one or more of propionic anhydride, butyric anhydride, isobutyric anhydride, valeric anhydride, isovaleric anhydride, hexanoic anhydride, isooctanoic anhydride, and isononanoic anhydride.
[0125] In some embodiments, the total mass hourly space velocity (MHSV) of the feedstock carboxylic acid and the feedstock anhydride is 0.2 h⁻¹. -1 ~1h -1 Specifically, the total mass airspeed includes, but is not limited to, 0.2 h. -1 0.3h -1 0.4h -1 0.5h -1 0.6h -1 0.7h -1 0.8h -1 0.9h -1 1h -1 Or the range between any two of the aforementioned.
[0126] In some embodiments, the feed molar ratio of the raw carboxylic acid to the raw anhydride is (2~5):1. Specifically, this feed molar ratio includes, but is not limited to: 2:1, 2.01:1, 2.03:1, 2.05:1, 2.07:1, 2.1:1, 2.5:1, 3:1, 3.5:1, 4:1, 4.5:1, 5:1, or a range between any two of the foregoing. Further, the feed molar ratio of the raw carboxylic acid to the raw anhydride is (2~2.1):1.
[0127] In some embodiments of the catalytic reactive distillation apparatus, the number of theoretical plates in the rectification section is 3 to 10. Specifically, the number of theoretical plates in the rectification section includes, but is not limited to, 5, 6, 7, 8, 9, 10, or any combination thereof.
[0128] In some embodiments of the catalytic reactive distillation apparatus, the number of theoretical plates in the catalytic reaction section is 3 to 10. Specifically, the number of theoretical plates in the catalytic reaction section includes, but is not limited to, 5, 6, 7, 8, 9, 10, or any combination thereof.
[0129] In some embodiments, the number of theoretical plates in the stripping section of the catalytic reactive distillation apparatus is 3 to 10; specifically, the number of theoretical plates in the stripping section includes, but is not limited to, 5, 6, 7, 8, 9, 10, or any combination thereof.
[0130] In some embodiments, the operating pressure of catalytic reactive distillation is 5 kPaA to 30 kPaA. Specifically, this operating pressure includes, but is not limited to, 5 kPaA, 10 kPaA, 15 kPaA, 20 kPaA, 25 kPaA, 30 kPaA, or any range between the two mentioned above.
[0131] In some embodiments, the reflux ratio of the catalytic reactive distillation is (1~5):1. Specifically, the reflux ratio includes, but is not limited to: 1:1, 1.5:1, 2:1, 2.5:1, 3:1, 3.5:1, 4:1, 4.5:1, 5:1, or any range between the foregoing.
[0132] In some embodiments, the temperature of catalytic reactive distillation is 100°C to 200°C. Specifically, this temperature includes, but is not limited to, 100°C, 130°C, 150°C, 170°C, 200°C, or any range between the two mentioned above.
[0133] In some embodiments, the purity of the product anhydride is ≥99.5%.
[0134] For experimental parameters not specified in the following specific embodiments, please refer to the guidelines given in this application document first, or refer to experimental manuals or other experimental methods known in the art, or refer to the experimental conditions recommended by the manufacturer.
[0135] The raw materials and reagents involved in the following specific embodiments can be obtained commercially or prepared by those skilled in the art using known methods.
[0136] Example 1
[0137] This embodiment describes a catalytic reactive distillation element, and its preparation method is as follows:
[0138] 1) Add silica sol, aluminum sulfate, and diethylpropylammonium iodide to water at a mass ratio of 1:0.3:0.05, and stir to mix. Add 3mm stainless steel Raschig ring packing (purchased from Jiangyin Jinxinta Packing Co., Ltd.) to the above mixture, with the packing mass accounting for 20% of the solution mass. Perform hydrothermal reaction at 110℃ for 25h. After removal, dry in a hot air oven at 120℃ for 20h to obtain molecular sieve packing.
[0139] 2) Add coupling agent KH-151, cobalt nitrate, and lanthanum chloride to water at a mass ratio of 1:5:5, which is 10 times the total mass of cobalt nitrate and lanthanum chloride. Stir and mix to prepare an aqueous solution. Add the molecular sieve packing obtained in step 1) at 10% of the mass of the salt solution. Then place it in a microwave heater for microwave-assisted hydrothermal reaction. The hydrothermal reaction temperature is 100℃, the hydrothermal reaction time is 20h, and the microwave frequency is 600MHz. Then filter out the packing element, wash with ethanol, and vacuum dry to obtain catalytic distillation element #1.
[0140] Example 2
[0141] This embodiment describes a catalytic reactive distillation element, and its preparation method is as follows:
[0142] 1) Tetraethyl orthosilicate, aluminum isopropoxide, and ethyltri-n-propylammonium iodide were added to water at a mass ratio of 1:1:0.02 in 40 times their total mass and stirred. 5 mm ceramic θ-ring filler (purchased from Jiangyin Jinxinta Filler Co., Ltd.) was added to the above mixture, with the filler mass accounting for 10% of the solution mass. The mixture was subjected to a hydrothermal reaction at 130℃ for 20 h. After removal, it was dried in a hot air oven at 130℃ for 25 h to obtain molecular sieve filler.
[0143] 2) Add coupling agent KH-561, copper chloride, and samarium phosphate to water at a mass ratio of 1:2:3, which is 15 times the total mass of copper chloride and samarium phosphate. Stir and mix to prepare an aqueous solution. Add the molecular sieve packing obtained in step 1) to the solution at 30% of the mass of the salt solution. Then, place the solution in a microwave heater for microwave-assisted hydrothermal reaction at a temperature of 130°C and a reaction time of 15 hours. Use a microwave frequency of 800MHz. After filtering out the packing element, washing with ethanol, and vacuum drying, the catalytic distillation element #2 is obtained.
[0144] Example 3
[0145] This embodiment describes a catalytic reactive distillation element, and its preparation method is as follows:
[0146] 1) Di-tert-butylsilane, boehmite, and triisooctylamine were added to water at a mass ratio of 1:0.06:0.5 in 60 times their total mass and stirred. 8mm stainless steel Pall ring packing (purchased from Jiangyin Jinxinta Packing Co., Ltd.) was added to the above mixture, with the packing mass accounting for 30% of the solution mass. The mixture was subjected to a hydrothermal reaction at 150℃ for 40 hours. After removal, it was dried in a hot air oven at 110℃ for 30 hours to obtain molecular sieve packing.
[0147] 2) Add the coupling agent tetraoctyl titanate, copper nitrate, and praseodymium chloride to water at a mass ratio of 1:3:1, which is 20 times the total mass of copper nitrate and praseodymium chloride. Stir and mix to prepare an aqueous solution. Add the molecular sieve packing obtained in step 1) to the solution at 20% of the mass of the salt solution. Then, place the solution in a microwave heater for a microwave-assisted hydrothermal reaction at a temperature of 120°C and a reaction time of 25 hours. The microwave frequency is 700MHz. After filtering out the packing element, washing with ethanol, and vacuum drying, the catalytic distillation element #3 is obtained.
[0148] Example 4
[0149] This embodiment is a catalytic reactive distillation element, prepared using the same method as in Example 1, with the main difference being:
[0150] In step 1), a hydrothermal reaction is carried out at 160°C for 25 hours.
[0151] Example 5
[0152] This embodiment is a catalytic reactive distillation element, prepared using the same method as in Example 1, with the main difference being:
[0153] In step 1), a hydrothermal reaction is carried out at 100°C for 25 hours.
[0154] Example 6
[0155] This embodiment is a catalytic reactive distillation element, prepared using the same method as in Example 1, with the main difference being:
[0156] In step 2), KH-151 is replaced by a coupling agent such as tetraoctyl titanate.
[0157] Example 7
[0158] This embodiment is a catalytic reactive distillation element, prepared using the same method as in Example 1, with the main difference being:
[0159] In step 2), copper chloride is used as a mass substitute for cobalt nitrate.
[0160] Example 8
[0161] This embodiment is a catalytic reactive distillation element, prepared using the same method as in Example 1, with the main difference being:
[0162] In step 2), the microwave frequency is adjusted to 1000MHz.
[0163] Comparative Example 1
[0164] The 5mm ceramic θ-ring packing (purchased from Jiangyin Jinxinta Packing Co., Ltd.) from Example 2 was directly used as the catalytic reaction distillation element.
[0165] Comparative Example 2
[0166] This comparative example is a bimetallic molecular sieve catalyst not supported on catalytic reactive distillation packing material, and its active components are similar to those in Example 1. The preparation method is as follows:
[0167] 1) Add silica sol, aluminum sulfate, and diethylpropyl ammonium iodide to water at a mass ratio of 1:0.3:0.05, and stir to mix. Perform hydrothermal reaction at 110℃ for 25 hours. After removal, dry in a hot air oven at 120℃ for 20 hours to obtain molecular sieve.
[0168] 2) Add coupling agent KH-151, cobalt nitrate, and lanthanum chloride to water at a mass ratio of 1:5:5, which is 10 times the total mass of cobalt nitrate and lanthanum chloride. Stir and mix to prepare an aqueous solution. Add the molecular sieve obtained in step 1) at 10% of the mass of the salt solution. Then place it in a microwave heater for microwave-assisted hydrothermal reaction at a temperature of 100℃ and a reaction time of 20h. Use a microwave frequency of 600MHz. After filtration, washing with ethanol, and vacuum drying, molecular sieve #1 is obtained.
[0169] Test example:
[0170] Catalytic reactive distillation was carried out using the catalytic reactive distillation elements prepared in the examples and comparative examples.
[0171] Equipment: Catalytic reactive distillation column, which includes a stripping section, a catalytic reaction section and a rectification section connected sequentially from the ground. The stripping section is filled with wire mesh corrugated packing (purchased from Jiangyin Jinxin Tower Packing Co., Ltd.), the catalytic reaction section is filled with catalytic reactive distillation elements or molecular sieves prepared in the examples and comparative examples, and the rectification section is filled with wire mesh corrugated packing (purchased from Jiangyin Jinxin Tower Packing Co., Ltd.).
[0172] Method: The carboxylic acid and acid anhydride are injected from the top and bottom of the catalytic reaction section, respectively.
[0173] Results: The purity of the product anhydride was determined by gas chromatography; the catalyst lifespan was determined by a long-term experimental method, namely, continuous operation of catalytic reactive distillation with reference to the corresponding examples or comparative examples until the purity of the product anhydride decreased by 0.2%, thus obtaining the catalyst lifespan.
[0174] For specific parameter controls and results, please refer to Table 1 below.
[0175] Table 1
[0176]
[0177] The technical features of the above embodiments can be combined in any way. For the sake of brevity, not all possible combinations of the technical features in the above embodiments are described. However, as long as there is no contradiction in the combination of these technical features, they should be considered to be within the scope of this specification.
[0178] The embodiments described above are merely illustrative of several implementation methods of this application, intended to facilitate a detailed understanding of the technical solutions of this application, but should not be construed as limiting the scope of protection of the patent application. It should be noted that those skilled in the art can make various modifications and improvements without departing from the concept of this application, and these all fall within the scope of protection of this application. It should be understood that technical solutions obtained by those skilled in the art based on the technical solutions provided in this application through logical analysis, reasoning, or limited experimentation are all within the scope of protection of the appended claims. Therefore, the scope of protection of this patent application should be determined by the content of the appended claims, and the specification can be used to interpret the content of the claims.
Claims
1. A method for preparing a catalytic reactive distillation element, characterized in that, Includes the following steps: A first solution is prepared by mixing a silicon source, an aluminum source, a template agent, and a first water. A second solution is prepared by mixing a coupling agent, a first metal salt, a second metal salt, and second water; the metal element in the first metal salt includes cobalt or copper, and the metal element in the second metal salt includes lanthanide rare earth elements. The catalytic reactive distillation packing was placed in the first solution for a first hydrothermal reaction, and then dried to prepare the molecular sieve supported packing. The molecular sieve-supported packing is placed in the second solution to carry out a second hydrothermal reaction to prepare the catalytic reaction distillation element.
2. The method for preparing the catalytic reactive distillation element according to claim 1, characterized in that, The catalytic reactive distillation packing has one or more of the following characteristics: (1) Specifications include one or more of Raschig rings, Pall rings, and θ rings; (2) The size is 2mm~8mm; (3) The materials include one or more of ceramics, stainless steel and titanium alloys.
3. The method for preparing the catalytic reactive distillation element according to claim 1 or 2, characterized in that, The conditions for preparing molecular sieve-supported packing materials include: (1) The silicon source includes one or more of silica sol, fumed silica, tetraethyl orthosilicate and di-tert-butylsilane; (2) The aluminum source includes one or more of aluminum isopropoxide, boehmite, and aluminum sulfate; (3) The template agent includes one or more of ethyltri-n-propylammonium iodide, diethylpropylammonium iodide, and triisooctylamine; (4) In the first solution, the mass ratio of the silicon source, the aluminum source and the template agent is 1:(0.02~1):(0.01~0.5); (5) The amount of the first water added is 10 to 100 times the total mass of the silicon source, the aluminum source and the template agent; (6) The mass percentage of the catalytic reactive distillation packing is 1% to 50% based on the mass of the first solution; (7) The temperature of the first hydrothermal reaction is 100℃~160℃, and the time of the first hydrothermal reaction is 20h~50h; (8) The drying temperature is 100℃~130℃ and the drying time is 20h~40h.
4. The method for preparing the catalytic reactive distillation element according to claim 1 or 2, characterized in that, The conditions for preparing catalytic reactive distillation elements include: (1) The coupling agent includes one or more of silane coupling agents and titanate coupling agents; Optionally, the silane coupling agent includes one or both of KH-151 and KH-561; Optionally, the titanate coupling agent includes one or more of tetraoctyl titanate, tetraethyl titanate, and tetrabutyl titanate; (2) In the second metal salt, the lanthanide rare earth element includes lanthanum, samarium, or praseodymium; (3) The mass ratio of the first metal salt to the second metal salt is (0.5~5):1; (4) The first metal salt and the second metal salt are each independently a phosphate, chloride, nitrate or sulfate; (5) The amount of the second water added is 2 to 20 times the total mass of the first metal salt and the second metal salt; (6) The amount of the coupling agent added is 1% to 50% of the total mass of the first metal salt and the second metal salt; (7) The mass percentage of the molecular sieve-supported packing material is 1% to 50% based on the mass of the second solution; (8) The second hydrothermal reaction is carried out with microwave assistance, and optionally, the microwave frequency is 500MHz~1000MHz; (9) The temperature of the second hydrothermal reaction is 100℃~130℃ and the time of the second hydrothermal reaction is 10h~30h.
5. The catalytic reactive distillation element prepared by the preparation method according to any one of claims 1 to 4.
6. The application of the catalytic reactive distillation element according to claim 5 in anhydride exchange reactions.
7. A catalytic reactive distillation apparatus, characterized in that, It includes a rectification section, a catalytic reaction section and a stripping section connected in sequence, wherein the catalytic reaction section is filled with the catalytic reaction rectification element as described in claim 5; Optionally, the rectifying section and the stripping section are filled with catalytic reactive distillation packing; further optionally, the catalytic reactive distillation packings filled in the rectifying section and the stripping section each independently include one or more of Raschig rings, Pall rings, θ rings, perforated plate corrugated packing and wire mesh corrugated packing.
8. A method for preparing acid anhydrides by catalytic reactive distillation, characterized in that, Catalytic reaction distillation is performed using the catalytic reaction distillation element as described in claim 5 or the catalytic reaction distillation equipment as described in claim 7. Optionally, catalytic reactive distillation is performed using the catalytic reactive distillation apparatus of claim 7, comprising the following steps: The raw material carboxylic acid and raw material anhydride are continuously injected into the catalytic reaction section to carry out anhydride exchange reaction, and the by-product carboxylic acid and product anhydride are continuously collected from the top of the rectification section and the side stream of the stripping section.
9. The method for preparing acid anhydrides by catalytic reactive distillation according to claim 8, characterized in that, The number of carbon atoms in the raw material anhydride is different from that in the product anhydride; Optionally, the raw material carboxylic acid includes organic carboxylic acids having 3 to 9 carbon atoms, and may include one or more of propionic acid, n-butyric acid, isobutyric acid, n-valeric acid, isovaleric acid, n-hexanoic acid, n-heptanoic acid, isooctanoic acid, and isononanoic acid. Optionally, the raw material anhydride includes organic carboxylic acid anhydrides with 2 to 4 carbon atoms, and may include one or more of acetic anhydride, propionic anhydride, n-butyric anhydride and isobutyric anhydride; Optionally, the product anhydride includes organic carboxylic acid anhydrides with 3 to 9 carbon atoms, and may include one or more of propionic anhydride, n-butyric anhydride, isobutyric anhydride, n-valeric anhydride, isovaleric anhydride, n-hexanoic anhydride, isooctanoic anhydride, and isononanoic anhydride.
10. The method for preparing acid anhydrides by catalytic reactive distillation according to claim 8 or 9, characterized in that, It has one or more of the following characteristics: (1) The total mass hourly space velocity (MHSV) of the feedstock carboxylic acid and the feedstock anhydride is 0.2 h⁻¹. -1 ~1h -1 ; (2) The feed molar ratio of the raw material carboxylic acid to the raw material anhydride is (2~5):1, and can be selected as (2~2.1):1; (3) In the catalytic reaction distillation equipment, the theoretical number of plates in the distillation section is 3 to 10; (4) In the catalytic reaction distillation equipment, the theoretical number of plates in the catalytic reaction section is 3 to 10; (5) In the catalytic reaction distillation equipment, the theoretical number of trays in the stripping section is 3 to 10; (6) The conditions for catalytic reactive distillation include: operating pressure of 5 kPaA to 30 kPaA, reflux ratio of (1 to 5):1, and temperature of 100℃ to 200℃.