Catalyst for preparing N-methyl o-phenylenediamine as well as preparation method and application of catalyst
By using SiO2, Al2O3, K2O, Na2O catalysts with a specific molar ratio, combined with a multi-step preparation method, the problem of low quality and purity of N-methyl orthophenyldiamine products in the prior art is solved, and high efficiency and low quality are achieved cost preparation effect.
Patent Information
- Application Number
- CN202411567602.5
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2024-11-05
- Publication Date
- 2025-02-14
AI Technical Summary
The catalysts used in the prior art for the preparation of N-methyl orthophenyldiamine are prone to produce by-products, resulting in low product quality and purity.
Using a catalyst with a molar ratio of SiO2, Al2O3, K2O and Na2O of (3.0-6.0):1:(0.03-0.3):(0.3-1), the preparation method is carried out through a multi-step preparation method, including seed crystal preparation, glue formation, and crystallization. and post-treatment to prepare efficient catalysts.
It improves the purity and yield of N-methyl orthophenyldiamine, solves the problem of by-products, and is simple in preparation and low in cost, suitable for industrial applications.
Abstract
Description
Technical Field
[0001] The invention relates to the technical field of catalyst production, in particular to a catalyst for preparing N-methyl-o-phenylenediamine and a preparation method and application thereof. Background Art
[0002] N-methyl-o-phenylenediamine is an important intermediate for the synthesis of telmisartan. The existing technical routes usually use methyl iodide, methyl bromide, dimethyl sulfate or dimethyl carbonate as alkylating agents. However, the common catalysts currently used to catalyze the production of N-methyl-o-phenylenediamine are prone to produce by-products such as N,N-dimethyl-o-phenylenediamine, making it difficult to ensure the quality of the product. At the same time, the purity of the prepared N-methyl-o-phenylenediamine is not high.
[0003] Therefore, there is an urgent need for a catalyst for preparing N-methyl-o-phenylenediamine and a preparation method and application thereof to solve the above technical problems. Summary of the invention
[0004] The object of the present invention is to provide a catalyst for preparing N-methyl-o-phenylenediamine with low cost and excellent performance and a preparation method thereof in view of the deficiencies in the prior art.
[0005] To achieve the above object, the present invention is implemented according to the following technical solutions:
[0006] A catalyst for preparing N-methyl-o-phenylenediamine, wherein the molar ratio of SiO2, Al2O3, K2O and Na2O in the catalyst is (3.0-6.0):1:(0.03-0.3):(0.3-1).
[0007] Preferably, the molar ratio of SiO2, Al2O3, K2O and Na2O in the catalyst is (3.0-5.0):1:(0.05-0.1):(0.5-1).
[0008] The preparation method of the catalyst for preparing N-methyl-o-phenylenediamine comprises the following steps:
[0009] S1 seed crystal preparation, according to the molar ratio of SiO2:Al2O3:Na2O:H2O=(5-15):1:(5-15):(100-200), mix and stir the silicon source, aluminum source, alkali source and water evenly, and then stir slowly for 12-36h to obtain seed crystals;
[0010] S2 gelling, according to the molar ratio of SiO2:Al2O3:K2O:Na2O:H2O=(5-15):1:(0.03-0.3):(3-5):(100-200), a silicon source, an aluminum source, a potassium source, a sodium source and water are mixed and stirred to obtain a mixture;
[0011] S3 crystallization, adding 5-15% of the mixture mass of seed crystals to the mixture, and crystallizing at a crystallization temperature of 80-100° C. for 8-12 hours;
[0012] S4 post-processing, filtering, washing, drying and calcining the reaction product obtained in step S3 to obtain a finished catalyst product.
[0013] Preferably, the silicon source is at least one of silica sol, sodium silicate, tetraethyl orthosilicate, and white carbon black; the aluminum source is at least one of pseudo-boehmite, alumina, sodium aluminate, and aluminum isopropoxide; the alkali source is at least one of sodium carbonate and sodium hydroxide; the potassium source is at least one of potassium carbonate, potassium hydroxide, and potassium oxalate; and the sodium source is at least one of sodium carbonate, sodium hydroxide, and sodium oxalate.
[0014] Further preferably, the silicon source is at least one of silica sol and sodium silicate; the aluminum source is at least one of sodium aluminate and pseudo-boehmite; the alkali source is at least one of sodium carbonate and sodium hydroxide; the potassium source is at least one of potassium carbonate and potassium hydroxide; and the sodium source is at least one of sodium carbonate and sodium hydroxide.
[0015] Preferably, in step S1, the silicon source, aluminum source, alkali source and water are mixed and stirred evenly according to the molar ratio of SiO2:Al2O3:Na2O:H2O=(8-10):1:(8-10):(160-200), and then slowly stirred for 12-24 hours.
[0016] Further preferably, the slow stirring speed in step S1 is 30 rpm.
[0017] Preferably, in step S2, the silicon source, aluminum source, potassium source, sodium source and water are mixed and stirred according to the molar ratio of SiO2:Al2O3:K2O:Na2O:H2O=(8-10):1:(0.05-0.1):(3-5):(160-200).
[0018] Preferably, in step S3, 8 to 10% of the mass of the mixture is added to the mixture, the crystallization temperature is 90 to 100° C., and the crystallization time is 8 to 10 hours.
[0019] Preferably, in step S4, the calcination temperature is 500-550° C., and the calcination time is 4-6 hours.
[0020] The invention also includes the use of the catalyst in synthesizing N-methyl o-phenylenediamine from o-phenylenediamine.
[0021] In the present invention, Si, Al, K, and Na elements involved in the catalyst, as well as Si, Al, K, and Na elements involved in the raw materials (silicon source, aluminum source, alkali source, potassium source, and sodium source) in the reaction process, are calculated as SiO2, Al2O3, K2O, and Na2O, respectively.
[0022] If the raw materials used in a certain step contain more than one element that needs to be involved in the corresponding molar ratio calculation, all the elements involved must be calculated. If the raw materials used contain H2O, and the steps involved in the raw materials need to calculate the amount of H2O, then the H2O in the raw materials also needs to be calculated.
[0023] Specifically, if the raw material used is sodium aluminate, the two elements Al and Na contained therein need to participate in the calculation of the corresponding molar ratio; in addition, if the raw material used is silica sol, the H2O contained in the silica sol also needs to participate in the calculation of the corresponding molar ratio.
[0024] Beneficial effects:
[0025] The present invention follows the tenet of green chemistry. Compared with other existing catalysts for the production of N-methyl-o-phenylenediamine, the present invention solves the problems that the prior art is difficult to ensure product quality and the purity of the prepared N-methyl-o-phenylenediamine is not high. At the same time, the present invention has the characteristics of simple preparation, low cost, high product yield, good selectivity, etc., and is suitable for industrial application. DETAILED DESCRIPTION
[0026] The present invention is further described below with reference to specific embodiments. The illustrative embodiments and descriptions of the present invention are used to explain the present invention but are not intended to limit the present invention.
[0027] All raw materials of the present invention have no particular limitation on their sources, and can be purchased from the market or prepared according to conventional methods known to those skilled in the art.
[0028] There is no particular limitation on the purity of all raw materials in the present invention, and the present invention preferably adopts the conventional purity used in the art.
[0029] The devices used in the present invention are not particularly limited and can be any of the commonly used devices in the art.
[0030] Example 1
[0031] Add 70g of sodium hydroxide and 30g of sodium aluminate (the Al element contained therein is calculated as Al2O3, and the Na element contained therein is calculated as Na2O) to 320mL of water, stir evenly, add 330g of sodium silicate solution (the sodium silicate content in the sodium silicate solution is 36wt%, the modulus of sodium silicate is 3.3, and the remainder is 64% of water; the Si element contained in the sodium silicate solution is calculated as SiO2, the Na element contained therein is calculated as Na2O, and the water contained therein is calculated as H2O), stir for 18h to obtain 750g of seed crystals. Add 350g of sodium hydroxide, 25g of potassium carbonate, and 330g of sodium aluminate (the Al element contained therein is calculated as Al2O3, and the Na element contained therein is calculated as Na2O) to 3400mL of water, stir evenly, add 3500g of silica sol with a solid content of 30wt% (the Si element contained therein is calculated as SiO2, and the water contained therein is calculated as H2O), and then add all the seed crystals prepared above, heat to 90°C under sealing, crystallize for 10h, filter, wash, dry, and calcine at 500°C for 5h. The catalyst 0.81Na2O:0.078K2O:1Al2O3:4.29SiO2 is obtained.
[0032] The catalyst is used with o-phenylenediamine as a raw material and dimethyl carbonate as an alkylating agent, and the reaction is carried out at 110° C. for 12 hours. N-methyl o-phenylenediamine is obtained by purification by column chromatography, with a yield of 80.9% and a purity of 97.2%.
[0033] Example 2
[0034] 93 g of sodium carbonate and 26 g of sodium aluminate (the Al element contained therein is calculated as Al2O3, and the Na element contained therein is calculated as Na2O) are added to 260 mL of water, and after stirring evenly, 310 g of sodium silicate solution is added (the sodium silicate content in the sodium silicate solution is 36 wt%, the modulus of sodium silicate is 3.3, and the remainder is 64% of water; the Si element contained in the sodium silicate solution is calculated as SiO2, the Na element contained therein is calculated as Na2O, and the water contained therein is calculated as H2O), and stirred for 24 hours to obtain 689 g of seed crystals. Add 110g of sodium hydroxide, 20g of potassium hydroxide, and 290g of pseudo-boehmite containing 67wt% of alumina (the Al element contained therein is calculated as Al2O3, and the water contained therein is calculated as H2O) to 4000mL of water, stir evenly, add 3500g of sodium silicate solution (in the sodium silicate solution, the sodium silicate content is 36wt%, the modulus of sodium silicate is 3.3, and the remainder is 64% of water; in the sodium silicate solution, the Si element contained therein is calculated as SiO2, the Na element contained therein is calculated as Na2O, and the water contained therein is calculated as H2O), then add all the seed crystals prepared above, heat to 98°C under sealing, crystallize for 8h, filter, wash, dry, and roast at 550°C for 4h. The catalyst 0.89Na2O:0.086K2O:1Al2O3:3.98SiO2 is obtained.
[0035] The catalyst was used with o-phenylenediamine as a raw material and dimethyl carbonate as an alkylating agent, and the reaction was carried out at 110° C. for 12 hours. N-methyl o-phenylenediamine was obtained by purification by column chromatography with a yield of 79.7% and a purity of 95.9%.
[0036] Example 3
[0037] Add 70g of sodium hydroxide and 30g of sodium aluminate (the Al element contained therein is calculated as Al2O3, and the Na element contained therein is calculated as Na2O) to 340mL of water, stir well, add 330g of sodium silicate solution (in the sodium silicate solution, the sodium silicate content is 36wt%, the modulus of sodium silicate is 3.3, and the remainder is 64% of water; in the sodium silicate solution, the Si element contained therein is calculated as SiO2, the Na element contained therein is calculated as Na2O, and the water contained therein is calculated as H2O), stir for 24h to obtain 760g of seed crystals. Add 80g sodium hydroxide, 15g potassium hydroxide, 320g sodium aluminate (the Al element contained therein is calculated as Al2O3, and the Na element contained therein is calculated as Na2O) to 3800mL water, stir evenly, add 3500g sodium silicate solution (in the sodium silicate solution, the sodium silicate content is 36wt%, the modulus of sodium silicate is 3.3, and the remainder is 64% water; in the sodium silicate solution, the Si element contained therein is calculated as SiO2, the Na element contained therein is calculated as Na2O, and the water contained therein is calculated as H2O), then add all the seed crystals prepared above, heat to 95°C under sealing, crystallize for 9h, filter, wash, dry, and roast at 520°C for 6h. The catalyst 0.99Na2O:0.062K2O:1Al2O3:3.66SiO2 is obtained.
[0038] The catalyst is used with o-phenylenediamine as a raw material and dimethyl carbonate as an alkylating agent, and the reaction is carried out at 110° C. for 12 hours. N-methyl o-phenylenediamine is obtained by purification by column chromatography, with a yield of 83.8% and a purity of 97.8%.
[0039] Comparative Example 1
[0040] The NaY molecular sieve purchased from the market was used as a catalyst, o-phenylenediamine was used as a raw material, dimethyl carbonate was used as an alkylating agent, the reaction was carried out at 110° C. for 12 hours, and N-methyl o-phenylenediamine was obtained by purification by column chromatography with a yield of 75.2% and a purity of 93.8%.
[0041] Comparative Example 2
[0042] 3A molecular sieve purchased on the market was used as a catalyst, o-phenylenediamine was used as a raw material, dimethyl carbonate was used as an alkylating agent, the reaction was carried out at 110° C. for 12 hours, and N-methyl o-phenylenediamine was obtained by purification by column chromatography with a yield of 70.5% and a purity of 90.2%.
[0043] The technical solution of the present invention is not limited to the above-mentioned specific embodiments. All technical variations made according to the technical solution of the present invention fall within the protection scope of the present invention.
Claims
1. A catalyst for preparing N-methyl-o-phenylenediamine, characterized in that: The molar ratio of SiO2, Al2O3, K2O and Na2O in the catalyst is (3.0-6.0):1:(0.03-0.3):(0.3-1).
2. The method for preparing a catalyst for preparing N-methyl-o-phenylenediamine according to claim 1, characterized in that: The following steps are involved: S1 seed crystal preparation, according to the molar ratio of SiO2:Al2O3:Na2O:H2O=(5-15):1:(5-15):(100-200), mix and stir the silicon source, aluminum source, alkali source and water evenly, and then stir slowly for 12-36h to obtain seed crystals; S2 gelling, according to the molar ratio of SiO2:Al2O3:K2O:Na2O:H2O=(5-15):1:(0.03-0.3):(3-5):(100-200), a silicon source, an aluminum source, a potassium source, a sodium source and water are mixed and stirred to obtain a mixture; S3 crystallization, adding 5-15% of the mixture mass of seed crystals to the mixture, and crystallizing at a crystallization temperature of 80-100° C. for 8-12 hours; S4 post-processing, filtering, washing, drying and calcining the reaction product obtained in step S3 to obtain a finished catalyst product.
3. The method for preparing a catalyst for preparing N-methyl-o-phenylenediamine according to claim 2, characterized in that: The silicon source is at least one of silica sol, sodium silicate, tetraethyl orthosilicate, and white carbon black; the aluminum source is at least one of pseudo-boehmite, alumina, sodium aluminate, and aluminum isopropoxide; the alkali source is at least one of sodium carbonate and sodium hydroxide; the potassium source is at least one of potassium carbonate, potassium hydroxide, and potassium oxalate; and the sodium source is at least one of sodium carbonate, sodium hydroxide, and sodium oxalate.
4. The method for preparing a catalyst for preparing N-methyl-o-phenylenediamine according to claim 3, characterized in that: The silicon source is at least one of silica sol and sodium silicate; the aluminum source is at least one of sodium aluminate and pseudo-boehmite; the alkali source is at least one of sodium carbonate and sodium hydroxide; the potassium source is at least one of potassium carbonate and potassium hydroxide; and the sodium source is at least one of sodium carbonate and sodium hydroxide.
5. The method for preparing a catalyst for preparing N-methyl-o-phenylenediamine according to claim 2, characterized in that: In the step S1, the silicon source, aluminum source, alkali source and water are mixed and stirred evenly according to the molar ratio of SiO2:Al2O3:Na2O:H2O=(8-10):1:(8-10):(160-200), and then slowly stirred for 12-24 hours.
6. The method for preparing a catalyst for preparing N-methyl-o-phenylenediamine according to claim 2, characterized in that: In the step S2, the silicon source, aluminum source, potassium source, sodium source and water are mixed and stirred according to the molar ratio of SiO2:Al2O3:K2O:Na2O:H2O=(8-10):1:(0.05-0.1):(3-5):(160-200).
7. The method for preparing a catalyst for preparing N-methyl-o-phenylenediamine according to claim 2, characterized in that: In the step S3, 8-10% of the mass of the mixture is added to the mixture with seed crystals, the crystallization temperature is 90-100° C., and the crystallization time is 8-10 hours.
8. The method for preparing a catalyst for preparing N-methyl-o-phenylenediamine according to claim 2, characterized in that: In the step S4, the calcination temperature is 500-550° C. and the calcination time is 4-6 hours.
9. Use of the catalyst according to claim 1 or the catalyst prepared by the preparation method according to any one of claims 2 to 8 in synthesizing N-methyl o-phenylenediamine from o-phenylenediamine.