Method and device for producing triacetonamine
Through multi-step reaction and the use of specific catalysts, the problem of many by-products in traditional triacetone amine synthesis is solved, effective cleavage of by-products and recovery of acetone is achieved, simplifying the purification process and improving process efficiency.
Patent Information
- Application Number
- CN202410332454.2
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Priority Date
- 2024-03-05
- Filing Date
- 2024-03-22
- Publication Date
- 2025-01-14
AI Technical Summary
A variety of by-products are produced in the traditional synthesis of triacetone amines, which increases the difficulty of subsequent purification and waste disposal problems. New methods are urgently needed to solve these problems.
Using a multi-step reaction process, the first acidic catalyst and the second acidic catalyst are used to form triacetone amines and separated by decompression distillation, followed by heat-cleaving by-products in the presence of amphiphilic catalyst to form acetone and lead them back to the A reactor realizes the recovery of by-products.
It effectively reduces the amount of by-products generated, simplifies the purification process, and realizes the recycling and reuse of by-products, improving the economic and efficiency of the process.
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Figure CN119306654A_ABST
Abstract
Description
Technical Field
[0001] The present invention relates to a process for producing triacetoneamine, and more particularly to cleaving the by-product to recover acetone. Background Art
[0002] Antioxidants and / or light stabilizers are often added during plastic processing to delay side reactions such as photodegradation, thermal degradation or deliquescence, further improving the life and weather resistance of the product. Triacetoneamine molecules are very important starting materials in light stabilizers. Traditionally, the method for synthesizing triacetoneamine is mainly a one-step reaction of acetone, ammonia, and ammonium nitrate. Although the yield of triacetoneamine is acceptable, many by-products are derived, which increases the difficulty of subsequent purification and waste disposal.
[0003] In summary, a new method for synthesizing triacetoneamine is urgently needed to solve the problem of by-products. Summary of the invention
[0004] An embodiment of the present invention provides a method for producing triacetoneamine, comprising: (a) introducing acetone and ammonia into a first reactor to form acetone in the presence of a first acidic catalyst; (b) introducing acetone and water into a second reactor to form triacetoneamine and a by-product in the presence of a second acidic catalyst, wherein the by-product is diacetone alcohol, diacetoneamine, mesityl oxide, 2,2,4,6-tetramethyl-2,3-dihydropyridine, or a combination thereof; (c) separating triacetoneamine and the by-product by vacuum distillation; (d) introducing the by-product and water into a third reactor to heat and crack the by-product in the presence of an amphiphilic catalyst to form acetone; and (e) introducing the acetone of step (d) back into the first reactor.
[0005] An apparatus for producing triacetoneamine provided by one embodiment of the present invention comprises: a first reactor, containing a first acidic catalyst therein, for receiving acetone and ammonia to form acetone; a second reactor, containing a second acidic catalyst therein, connected to the first reactor and a water source to receive acetone and water respectively to form triacetoneamine and a by-product, wherein the by-product is diacetone alcohol, diacetoneamine, mesityl oxide, 2,2,4,6-tetramethyl-2,3-dihydropyridine, or a combination thereof; a distiller, connected to the second reactor to receive triacetoneamine and the by-product, and to separate triacetoneamine and the by-product by vacuum distillation; and a third reactor, containing an amphiphilic catalyst therein, connected to the distiller and a water source to receive the by-product and water respectively, for heating and cracking the by-product to form acetone, wherein the third reactor is connected to the first reactor to guide the acetone in the third reaction gas back to the first reactor. BRIEF DESCRIPTION OF THE DRAWINGS
[0006] Figure 1 FIG. 1 is a schematic diagram of a device for producing triacetoneamine in one embodiment of the present invention.
[0007] Wherein, the reference numerals are:
[0008] 11. First Reactor
[0009] 13. Second Reactor
[0010] 15 Water
[0011] 17. Still
[0012] 19 The third reactor
[0013] 100 Installations DETAILED DESCRIPTION
[0014] An apparatus 100 for producing triacetoneamine provided by an embodiment of the present invention is as follows: Figure 1 The device 100 includes a first reactor 11, which contains a first acidic catalyst therein, for receiving acetone and ammonia to form acetonin (Acetonin, ACTN, whose chemical structure is In some embodiments, the first acidic catalyst may be Amberlyst 15 (available from ACROS, Alfa Aesar, or DuPont).
[0015] The device 100 also includes a second reactor 13, which contains a second acidic catalyst and is connected to the first reactor 11 and the water source 15 to receive acetonine and water to form triacetonamine (TAA, whose chemical structure is ) and byproducts. The second acidic catalyst may be Amberlyst 15 (available from ACROS, Alfa Aesar, or DuPont). In some embodiments, the first acidic catalyst and the second acidic catalyst may be the same. In other embodiments, the first acidic catalyst and the second acidic catalyst may be different. The byproduct is diacetone alcohol (DAA, whose chemical structure is ), diacetone amine (DAAM, whose chemical structure is ), mesityl oxide (MO, whose chemical structure is ), 2,2,4,6-tetramethyl-2,3-dihydro pyridine (TMDP, whose chemical structure is ), or a combination of the above.
[0016] The apparatus 100 also includes a distiller 17 connected to the second reactor 13 to receive TAA and by-products and separate TAA and by-products by distillation under reduced pressure.
[0017] The apparatus 100 also includes a third reactor 19, which contains an amphiphilic catalyst therein and is connected to the distiller 17 and the water source 15 to receive the byproduct and water, respectively. The third reactor 19 is used to heat the cracked byproduct to form acetone. The third reactor 19 is further connected to the first reactor 11 to guide the acetone back to the first reactor 11. In some embodiments, the chemical structure of the amphiphilic catalyst is Where R 1 C 4-10 The alkyl group, R 2 Each is independent of C 4-16 The alkyl group, R 3 is -NH2 or -OH, R 4 C 2-6 The alkylene group, R 5 is -NH- or -O-, and n=0-4. 1 If the byproduct is a lone electron pair (i.e., 1,4-diazabicyclo[2.2.2]octane, DABCO) or a low carbon (e.g., ≤C3) alkyl group, it is not possible to effectively cleave the byproduct to form acetone. 2 If the carbon number of n is less than 4 (e.g., 1 to 3), the byproduct cannot be cracked to form acetone. If the number of n is too large (e.g., greater than 4), the effect of the amphiphilic catalyst in cracking the byproduct to form acetone is poor. It can be seen from the experiment that after the above amphiphilic catalyst is used multiple times, the effect of cracking the byproduct can still be maintained to a certain extent without being greatly attenuated.
[0018] A method for producing triacetoneamine provided by one embodiment of the present invention comprises: (a) introducing acetone and ammonia into a first reactor 11 to form acetone in the presence of a first acidic catalyst. In some embodiments, the temperature of the first reactor is 20°C to 40°C. If the temperature of the first reactor 11 is too low, the acetone conversion rate is poor and the acetone yield is reduced. If the temperature of the first reactor 11 is too high, the selectivity of acetone decreases and by-products other than acetone are easily generated. In some embodiments, the molar ratio of acetone to ammonia is 1:1 to 20:1. If the amount of acetone is too high, the solid content of acetone decreases and affects the production capacity. If the amount of acetone is too low, the residual unreacted ammonia enters the second reactor, reducing the selectivity of triacetoneamine.
[0019] Then (b) acetone and water are introduced into the second reactor 13 to form triacetone amine and byproducts in the presence of a second acidic catalyst, and the byproducts are diacetone alcohol, diacetone amine, mesityl oxide, 2,2,4,6-tetramethyl-2,3-dihydropyridine, or a combination thereof. In some embodiments, the water may come from the water source 15 of the aforementioned device 100. In some embodiments, the temperature of the second reactor is 60° C. to 90° C. If the temperature of the second reactor 13 is too low, the conversion rate of acetone is poor and the yield of triacetone amine is reduced. If the temperature of the second reactor 13 is too high, the selectivity of triacetone amine decreases and byproducts other than triacetone amine are easily generated.
[0020] Then (c) triacetoneamine and by-products are separated by vacuum distillation. For example, the vacuum distillation step can be performed in the distiller 17 of the apparatus 100.
[0021] Then (d) the by-product and water are introduced into the third reactor 19, and the by-product is heated and cracked in the presence of an amphiphilic catalyst to form acetone. For example, the water can come from the water source 15 of the aforementioned device 100. In some embodiments, the molar ratio of the amphiphilic catalyst to the by-product is 1:5 to 1:40. If the amount of the amphiphilic catalyst is too low, the by-product cannot be effectively cracked into acetone. If the amount of the amphiphilic catalyst is too high, the process economy is reduced. In some embodiments, the temperature of the third reactor 19 is 70°C to 90°C. If the temperature of the third reactor 19 is too low, the cracking efficiency is reduced. If the temperature of the third reactor 19 is too high, the process consumes energy and reduces the process economy.
[0022] Then (e) the acetone from step (d) is introduced back into the first reactor 11, so that the recovered acetone is used again to form acetonin, and acetonin can react with water to form triacetoneamine and by-products again.
[0023] In order to make the above contents and other purposes, features, and advantages of the present invention more clearly understood, embodiments are given below with reference to the accompanying drawings for detailed description as follows:
[0024] [Example]
[0025] Synthesis example 1
[0026] Take 10.0g of 1,4-diazabicyclo[2.2.2]octane (DABCO) and 14.7g of 1-bromohexane (1-Bromohexane) and dissolve them in 200mL of ethyl acetate. Stir and react at room temperature for 72 hours. After the reaction is completed, remove the solvent to collect the white solid. Dissolve the white solid in ethanol (200mL) and add 4.9g of potassium hydroxide to precipitate potassium bromide. Collect the filtrate after filtration, and remove the solvent to obtain a white liquid (18.65g, 98%). The hydrogen spectrum of the product is as follows:1 H NMR (400MHz, D2O, 298K): 3.35 (t, 6H), 3.15 (m, 8H), 1.71 (m, 2H), 1.29 (m, 6H), 0.83 (t, 3H). The chemical structure of the product is as follows:
[0027] Synthesis example 2
[0028] 19.5 g of hexadecyltrimethyl ammonium bromide and 3.0 g of potassium hydroxide were added to 200 mL of ethanol to precipitate potassium bromide. After stirring, the filtrate was collected by filtration. The solvent of the filtrate was removed to obtain a light yellow liquid (15.91 g, 99%). The hydrogen spectrum of the product is as follows: 1 H NMR (400MHz, D2O, 298K): 3.32 (t, 2H), 3.12 (s, 9H), 1.75 (m, 2H), 1.31 (m, 26H), 1.87 (t, 3H). The chemical structure of the product is as follows:
[0029] Synthesis example 3
[0030] Take 5.0g of DABCO and 4.9g of 1-bromoethane and dissolve them in 100mL of ethyl acetate. Stir and react at room temperature for 72 hours. After the reaction is completed, remove the solvent to collect the white solid. Dissolve the white solid in ethanol (100mL) and add 2.4g of potassium hydroxide to precipitate potassium bromide. Collect the filtrate after filtration and remove the solvent to obtain the product. The hydrogen spectrum of the product is as follows: 1 H NMR (400MHz, D2O, 298K): 3.39 (m, 8H), 3.24 (t, 6H), 1.37 (t, 3H). The chemical structure of the product is as follows:
[0031] Synthesis example 4
[0032] Take 5.0g of DABCO and 5.5g of 1-bromopropane and dissolve them in 100mL of ethyl acetate. Stir the reaction at room temperature for 72 hours. After the reaction is completed, remove the solvent to collect the white solid. Dissolve the white solid in ethanol (100mL) and add 2.4g of potassium hydroxide to precipitate potassium bromide. Collect the filtrate after filtration and remove the solvent to obtain the product. The hydrogen spectrum of the product is as follows: 1 H NMR (400MHz, D2O, 298K): 3.42 (t, 6H), 3.23 (m, 8H), 1.80 (q, 2H), 0.99 (t, 3H). The chemical structure of the product is as follows:
[0033] Synthesis example 5
[0034] Take 5.0g of DABCO and 8.6g of 1-bromooctane (1-Bromooctane) and dissolve them in 100mL of ethyl acetate. Stir the reaction at room temperature for 72 hours. After the reaction is completed, remove the solvent to collect the white solid. Dissolve the white solid in ethanol (100mL) and add 2.4g of potassium hydroxide to precipitate potassium bromide. Collect the filtrate after filtration and remove the solvent to obtain the product. The hydrogen spectrum of the product is as follows: 1 H NMR (400 MHz, D2O, 298K): 3.43 (t, 6H), 3.25 (m, 8H), 1.35 (m, 10H), 0.91 (t, 3H). The chemical structure of the product is as follows:
[0035] Example 1
[0036] 100 g of mesityl oxide (MO), 25 g of diacetone alcohol (DAA), 100 g of water, and 15.7 g of the product of Synthesis Example 1 were mixed and heated to 85° C. for 3 hours. The product after the reaction was distilled to obtain 125.6 g of acetone (yield: 87%).
[0037] Next, 100 g of MO, 25 g of DAA, and 100 g of water were mixed with the product of Synthesis Example 1 after the first use, and then heated to 85° C. to react for 3 hours. The product after the reaction was distilled to obtain 127.5 g of acetone (yield: 89%).
[0038] Next, 100 g of MO, 25 g of DAA, and 100 g of water were mixed with the product of Synthesis Example 1 after the second use, and then heated to 85° C. to react for 3 hours. The product after the reaction was distilled to obtain 123.2 g of acetone (yield: 86%).
[0039] From the above, it can be seen that after multiple uses, the effect of the product of Synthesis Example 1 on cracking MO and DAA can still be maintained at a certain level without being greatly attenuated.
[0040] Example 2
[0041] 100 g of MO, 25 g of DAA, 100 g of water, and 16.5 g of the product of Synthesis Example 2 were mixed and heated to 85° C. for reaction for 3 hours. The product after the reaction was distilled to obtain 124.1 g of acetone (yield: 85%).
[0042] Example 3
[0043] 100 g of MO, 25 g of DAA, 100 g of water, and 12.0 g of the product of Synthesis Example 5 were mixed and heated to 85° C. for reaction for 3 hours. The product after the reaction was distilled to obtain 132.1 g of acetone (yield: 92%).
[0044] Example 4
[0045] 100 g of MO, 25 g of DAA, 100 g of water, and 25.0 g of a 40 wt % aqueous solution of tetrabutylammonium hydroxide (TBAH) were mixed and heated to 85° C. for 3 hours. The product after the reaction was distilled to obtain 120.6 g of acetone (yield: 84%).
[0046] Example 5
[0047] 100 g of MO, 25 g of DAA, 100 g of water, and 10 g of monoethanolamine (MEA) were mixed and heated to 80° C. to 85° C. for 2 hours. The product after the reaction was distilled to obtain 123.4 g of acetone (yield: 85%).
[0048] Example 6
[0049] 100 g of MO, 25 g of DAA, 100 g of water, and 10 g of triethylenetetramine (TETA) were mixed and heated to 80° C. to 85° C. for 2 hours. The product after the reaction was distilled to obtain 124.3 g of acetone (yield: 85%).
[0050] Comparative Example 1
[0051] 100 g of MO, 25 g of DAA, 100 g of water, and 10 g of Jeffamine D-230 (purchased from Huntsman, with a chemical structure of ) were mixed and heated to 85° C. to 90° C. to react for 6 hours. The product after the reaction was distilled to obtain 21.4 g of acetone (yield: 15%).
[0052] Comparative Example 2
[0053] 100 g of MO, 25 g of DAA, 100 g of water, and 9 g of aqueous ammonia (30 wt%) were mixed and heated to 85° C. to react for 4 hours. The product after the reaction was distilled and acetone was not obtained.
[0054] Comparative Example 3
[0055] 100 g of MO, 25 g of DAA, 100 g of water, and 10 g of NaOH were mixed and heated to 85° C. to react for 3 hours. The product after the reaction was distilled to obtain 102.1 g of acetone (yield: 71%).
[0056] Comparative Example 4
[0057] 100 g of MO, 25 g of DAA, 100 g of water, and 10 g of DABCO were mixed and heated to 85° C. to react for 3 hours. The product after the reaction was distilled without obtaining acetone.
[0058] Comparative Example 5
[0059] 100 g of MO, 25 g of DAA, 100 g of water, and 10 g of decanediamine were mixed and heated to 85° C. to react for 3 hours. The product after the reaction was distilled to obtain 23.2 g of acetone (yield: 16%).
[0060] Comparative Example 6
[0061] 100 g of MO, 25 g of DAA, 100 g of water, and 10.0 g of the product of Synthesis Example 3 were mixed and heated to 85° C. for reaction for 3 hours. The product after the reaction was distilled to obtain 41.0 g of acetone (yield: 29%).
[0062] Comparative Example 7
[0063] 100 g of MO, 25 g of DAA, 100 g of water, and 10.0 g of the product of Synthesis Example 4 were mixed and heated to 85° C. for reaction for 3 hours. The product after the reaction was distilled to obtain 51.3 g of acetone (yield: 36%).
[0064] Example a-1
[0065] A fixed bed reactor was set up with an inner diameter of 12.7 mm and a tube length of 760 mm, and 20 mL of sulfonic acid resin Amberlyst 15 (purchased from ACROS, Alfa Aesar, or DuPont) was loaded as an acid catalyst. The temperature of the fixed bed reactor was maintained at 30°C and the pressure was maintained at 10 kg / cm 2 .
[0066] Acetone and liquid ammonia (molar ratio of 1.4:1) were introduced into a fixed bed reactor, and the acetone space velocity (LHSV) was 1.15h -1 , while the LHSV of liquid ammonia is 0.25h -1 The product flowing out of the fixed bed reactor was subjected to gas-liquid separation to obtain a crude product of acetonide. According to gas chromatography analysis, the selectivity of the crude product of acetonide was 100% and the yield was 51%.
[0067] 70 g of crude pyruvate, 3.15 g of water (4.5 wt%), and 8 g of Amberlyst 15 were added to the autoclave reactor and heated to 75 °C and maintained at a pressure of 10 kg / cm 2 The reaction was continued for 6 hours to obtain a crude product of triacetoneamine. The crude product was analyzed by gas chromatography, and the yield of TAA was 4%, and the rest was by-products.
[0068] Example a-2
[0069] Acetone and liquid ammonia (molar ratio of 2.8:1) were introduced into the fixed bed reactor of Example a-1, and the LHSV of acetone was 1.15h -1 , while the LHSV of liquid ammonia is 0.13h -1 The product flowing out of the fixed bed reactor was subjected to gas-liquid separation to obtain a crude product of acetonide. According to gas chromatography analysis, the selectivity of the crude product of acetonide was 100% and the yield was 77%.
[0070] 70 g of crude pyruvate, 3.15 g of water (4.5 wt%), and 8 g of Amberlyst 15 were added to the autoclave reactor and heated to 75 °C and maintained at a pressure of 10 kg / cm 2 The reaction was continued for 6 hours to obtain a crude triacetoneamine product. The crude product was analyzed by gas chromatography, and the yield of TAA was 45%, and the rest was by-products.
[0071] Example a-3
[0072] Acetone and liquid ammonia (molar ratio of 5.7:1) were introduced into the fixed bed reactor of Example a-1, and the LHSV of acetone was 1.15h -1 , while the LHSV of liquid ammonia is 0.06h -1 The product flowing out of the fixed bed reactor was subjected to gas-liquid separation to obtain a crude product of acetonide. According to gas chromatography analysis, the selectivity of the crude product of acetonide was 100% and the yield was 91%.
[0073] 70 g of crude pyruvate, 3.15 g of water (4.5 wt%), and 8 g of Amberlyst 15 were added to the autoclave reactor and heated to 75 °C and maintained at a pressure of 10 kg / cm 2 The reaction was continued for 6 hours to obtain a crude triacetoneamine product. The crude product was analyzed by gas chromatography, and the yield of TAA was 84%, and the rest was by-products.
[0074] Example a-4
[0075] Acetone and liquid ammonia (molar ratio of 8.1:1) were introduced into the fixed bed reactor of Example a-1, and the LHSV of acetone was 1.15h -1 , while the LHSV of liquid ammonia is 0.04h -1The product flowing out of the fixed bed reactor was subjected to gas-liquid separation to obtain a crude product of acetonide. According to gas chromatography analysis, the selectivity of the crude product of acetonide was 100% and the yield was 98%.
[0076] 70 g of crude pyruvate, 3.15 g of water (4.5 wt%), and 8 g of Amberlyst 15 were added to the autoclave reactor and heated to 75 °C and maintained at a pressure of 10 kg / cm 2 The reaction was continued for 6 hours to obtain a crude triacetoneamine product. The crude product was analyzed by gas chromatography, and the yield of TAA was 93%, and the rest was by-products.
[0077] Example a-5
[0078] The crude product of Example a-3 was distilled to obtain light boiling products. 25 g of the light boiling products, 20 g of water, and 4 g of the product of Synthesis Example 1 were mixed and heated to 80°C to 90°C and reacted for 3 hours. The product after the reaction contained a large amount of acetone.
[0079] The recovered acetone and liquid ammonia (molar ratio of 5.7:1) were introduced into the fixed bed reactor of Example a-1. The LHSV of acetone was 1.15 h -1 , while the LHSV of liquid ammonia is 0.06h -1 The product flowing out of the fixed bed reactor was subjected to gas-liquid separation to obtain a crude product of acetonide. According to gas chromatography analysis, the selectivity of the crude product of acetonide was 100% and the yield was 92%.
[0080] 70 g of crude acetonide, 3.15 g of water (4.5 wt%), and 8 g of Amberlyst 15 were added to the autoclave reactor and heated to 75 °C and maintained at a pressure of 10 kg / cm 2 The reaction was continued for 6 hours to obtain a crude triacetoneamine product. The crude product was analyzed by gas chromatography, and the yield of TAA was 83%, and the rest was by-products. As can be seen from Example a-5, the acetone obtained by cleavage of the by-products can be used again to prepare acetonin, and acetonin can be used to prepare triacetoneamine.
[0081] Example a-6
[0082] A fixed bed reactor was set up with an inner diameter of 12.7 mm and a tube length of 760 mm, and 20 mL of sulfonic acid resin Amberlyst 15 was loaded as an acid catalyst. The temperature of the fixed bed reactor was maintained at 35°C and the pressure was maintained at 10 kg / cm 2 .
[0083] Acetone and liquid ammonia (molar ratio of 5.7:1) were introduced into a fixed bed reactor, and the LHSV of acetone was 1.15h -1 , while the LHSV of liquid ammonia is 0.06h -1The product flowing out of the fixed bed reactor was subjected to gas-liquid separation to obtain a crude product of acetonide. According to gas chromatography analysis, the selectivity of the crude product of acetonide was 100% and the yield was 94%.
[0084] Example a-7
[0085] A fixed bed reactor was set up with an inner diameter of 12.7 mm and a tube length of 800 mm, and 20 mL of sulfonic acid resin Amberlyst 15 was loaded as an acid catalyst. The temperature of the fixed bed reactor was maintained at 75°C and the pressure was maintained at 10 kg / cm 2 .
[0086] The crude acetone product obtained in Example a-3 was introduced into a fixed bed reactor after adding water (the weight ratio of the crude acetone product to water was 100:4.5), and the LHSV of the crude acetone product and water was 0.6h -1 The products flowing out of the fixed bed were analyzed by gas chromatography, and the yield of TAA was 95%, and the rest were by-products. As can be seen from Example a-7, the reactor for the reaction of acetonide and water can be a fixed bed reactor in addition to a high-pressure reactor.
[0087] Example 7
[0088] The crude product of Example a-3 was distilled to obtain light boiling products. Analysis by gas chromatography revealed that the composition contained 0.16 parts of acetone, 0.06 parts of MO, 0.51 parts of TMDP, 0.35 parts of ACTN, 0.10 parts of DAAM, 0.41 parts of DAA, and 0.27 parts of TAA (relative to the integrated area of the internal standard isopropanol (1 part)).
[0089] Take 25g of light boiling materials, 20g of water, and 4g of the product of Synthesis Example 1, mix them, heat to 80°C to 90°C, and react for 3 hours. The product after the reaction was analyzed by gas chromatography, and it was found that its composition contained 1.18 parts of acetone, 0 parts of MO, 1.10 parts of TMDP, 0 parts of ACTN, 0 parts of DAAM, 0 parts of DAA, and 0.32 parts of TAA (relative to the integral area (1 part) of the internal standard isopropanol). From the above, it can be seen that the product of Synthesis Example 1 can effectively crack the by-product of TAA into acetone.
[0090] Take 25g of light boiling products, 20g of water, and 4g of sodium hydroxide, mix them, heat to 80℃ to 90℃ and react for 3 hours. The product after the reaction was analyzed by gas chromatography, and its composition contained 1.14 parts of acetone, 0 parts of MO, 1.2 parts of TMDP, 0 parts of ACTN, 0 parts of DAAM, 0 parts of DAA, and 0.32 parts of TAA (relative to the integral area (1 part) of the internal standard isopropanol). From the above, it can be seen that the effect of sodium hydroxide on the by-product of TAA to acetone is lower than that of the product of Synthesis Example 1.
[0091] Example 8
[0092] The crude product of Example a-3 was distilled to obtain light boiling products. Analysis by gas chromatography revealed that the composition contained 0.34 parts of acetone, 0.05 parts of MO, 0.63 parts of TMDP, 1.02 parts of ACTN, 0.32 parts of DAAM, 0.69 parts of DAA, and 0.48 parts of TAA (relative to the integrated area of the internal standard isopropanol (1 part)).
[0093] Take 25g of light boiling materials, 20g of water, and 4g of the product of Synthesis Example 2, mix them, heat to 80°C to 90°C, and react for 3 hours. The product after the reaction was analyzed by gas chromatography, and it was found that its composition contained 2.12 parts of acetone, 0 parts of MO, 1.84 parts of TMDP, 0 parts of ACTN, 0 parts of DAAM, 0 parts of DAA, and 0.52 parts of TAA (relative to the integral area (1 part) of the internal standard isopropanol). As can be seen from the above, the product of Synthesis Example 2 can effectively crack the by-product of TAA into acetone.
[0094] Take 25g of light boiling products, 20g of water, and 4g of sodium hydroxide, mix them, heat to 80°C to 90°C and react for 3 hours. The product after the reaction was analyzed by gas chromatography, and its composition contained 1.62 parts of acetone, 0 parts of MO, 2.06 parts of TMDP, 0 parts of ACTN, 0 parts of DAAM, 0 parts of DAA, and 0.61 parts of TAA (relative to the integral area (1 part) of the internal standard isopropanol). From the above, it can be seen that the effect of sodium hydroxide on the by-product of TAA to acetone is significantly lower than the product of Synthesis Example 2.
[0095] Although the present invention has been disclosed as above with several embodiments, they are not intended to limit the present invention. Anyone with common knowledge in the technical field can make any changes and modifications without departing from the spirit and scope of the present invention. Therefore, the scope of protection of the present invention shall be based on the scope defined by the attached claims.
Claims
1. A method for producing triacetoneamine, comprising: (a) introducing acetone and ammonia into a first reactor to form acetone in the presence of a first acidic catalyst; (b) introducing the acetone and water into a second reactor to form triacetone amine and a by-product in the presence of a second acidic catalyst, wherein the by-product is diacetone alcohol, diacetone amine, mesityl oxide, 2,2,4,6-tetramethyl-2,3-dihydropyridine, or a combination thereof; (c) separating the triacetoneamine and the by-product by distillation under reduced pressure; (d) introducing the by-product and water into a third reactor, and heating and cracking the by-product in the presence of an amphiphilic catalyst to form acetone; and (e) returning the acetone from step (d) to the first reactor.
2. The method for producing triacetoneamine according to claim 1, wherein the chemical structure of the amphiphilic catalyst is Where R 1 C 4-10 The alkyl group, R 2 Each is independent of C 4-16 The alkyl group, R 3 is -NH2 or -OH, R 4 C 2-6 The alkylene group, R 5 is -NH- or -O-, and n=0-4.
3. The method for producing triacetoneamine according to claim 1, wherein the molar ratio of the amphiphilic catalyst to the by-product is 1:5 to 1:
40.
4. The method for producing triacetoneamine according to claim 1, wherein the temperature of the first reactor is 20°C to 40°C.
5. The method for producing triacetoneamine according to claim 1, wherein the temperature of the second reactor is 60°C to 90°C.
6. The method for producing triacetoneamine according to claim 1, wherein the molar ratio of acetone to ammonia is 1:1 to 20:
1.
7. The method for producing triacetoneamine according to claim 1, wherein the temperature of the third reactor is 70°C to 90°C.
8. A device for producing triacetoneamine, comprising: a first reactor, comprising a first acidic catalyst therein, for receiving acetone and ammonia to form acetonin; a second reactor, comprising a second acidic catalyst therein, and connected to the first reactor and a water source to receive the acetone and water respectively to form triacetoneamine and a by-product, wherein the by-product is diacetone alcohol, diacetoneamine, mesityl oxide, 2,2,4,6-tetramethyl-2,3-dihydropyridine, or a combination thereof; a distiller connected to the second reactor to receive the triacetoneamine and the by-product and separate the triacetoneamine and the by-product by distillation under reduced pressure; and a third reactor, comprising an amphiphilic catalyst therein, connected to the distiller and the water source to receive the by-product and water respectively, and used for heating and cracking the by-product to form acetone, The third reactor is connected to the first reactor so as to guide the acetone in the third reactor back to the first reactor.
9. The apparatus for producing triacetoneamine according to claim 8, wherein the chemical structure of the amphiphilic catalyst is Where R 1 C 4-10 The alkyl group, R 2 Each is independent of C 4-16 The alkyl group, R 3 is -NH2 or -OH, R 4 C 2-6 The alkylene group, R 5 is -NH- or -O-, and n=0-4.