Preparation method of bio-based tromethamine

Abstract

The invention provides a preparation method of bio-based tromethamine, which comprises the following steps: S1, taking bio-based 1, 3-dihydroxy acetone, hydrogen peroxide and an ammonia source as raw materials, and carrying out oxidation nitration reaction under the action of a catalyst to obtain 1, 3-dihydroxy nitropropane; and S2, adding a hydroxymethylation reagent into the 1, 3-dihydroxy nitropropane, carrying out condensation reaction under an alkaline condition, and carrying out hydrogenation reduction to obtain the bio-based tromethamine. According to the invention, a sustainable synthesis route based on bio-based raw materials is developed, renewable 1, 3-dihydroxy acetone which can be prepared through microbial fermentation is taken as a starting point, and the bio-based tromethamine is efficiently prepared through an optimized three-step method of oxidation nitration, condensation and reduction. According to the route, the reaction efficiency and selectivity are remarkably improved, the raw material cost and the process environment influence are effectively reduced, and a solid foundation is laid for green and economic production of bio-based tromethamine.

Description

Technical Field

[0001] This invention belongs to the field of organic synthesis, specifically relating to a method for preparing bio-based tromethamine. Background Technology

[0002] Tromethamine is an indispensable buffer and synthetic intermediate in fields such as biochemistry, molecular biology, pharmaceuticals, and diagnostic reagents. Currently, the main industrial synthesis route is based on petroleum-derived nitromethane. However, this route has significant drawbacks: it is highly dependent on non-renewable fossil resources, exacerbating the resource depletion crisis; and the petroleum extraction, refining, and some synthetic steps pose potential environmental pollution risks.

[0003] To address these challenges and meet the requirements of sustainable development, developing environmentally friendly tromethamine based on renewable resources is crucial. In recent years, utilizing biotechnologies such as microbial fermentation and biocatalysis to convert renewable biomass resources like sugars and cellulose hydrolysates into bio-based chemicals has become a research hotspot. Bio-based tris(hydroxymethyl)aminomethane is one such representative product of this trend.

[0004] Therefore, developing a method for preparing bio-based tromethamine has become an urgent problem to be solved. Summary of the Invention

[0005] To address the shortcomings of existing technologies, the present invention aims to provide a technical solution that achieves this objective. The present invention employs the following technical solution:

[0006] The purpose of this invention is to provide a method for preparing bio-based tromethamine, comprising the following steps:

[0007] S1. Using bio-based 1,3-dihydroxyacetone, hydrogen peroxide, and ammonia source as raw materials, 1,3-dihydroxynitropropane is obtained by oxidative nitration under the action of a catalyst.

[0008] S2. A hydroxymethylating agent is added to 1,3-dihydroxynitropropane, and a condensation reaction occurs under alkaline conditions. Then, the mixture is hydrogenated and reduced to obtain bio-based tromethamine.

[0009] 1,3-Dihydroxyacetone (DHA) is a sweet-tasting white powdery crystalline compound. As an emerging bio-based compound, it has become a key candidate to replace petroleum-based materials due to its 100% renewable source (obtained through microbial fermentation) and green production process. Its molecule possesses both primary hydroxyl and ketone groups, endowing it with high reactivity, allowing it to be derived into polymers, functional additives, and cross-linking agents. It also possesses FDA-approved biosafety, biodegradability, and unique antibacterial properties.

[0010] Specifically, the catalyst includes TS-1 and nickel-doped Ni@TS-1. The TS-1 used in this invention is a commercially available titanium-silicon molecular sieve, while the nickel-doped Ni@TS-1 is self-prepared. The inventors discovered that using nickel-doped Ni@TS-1 as a catalyst results in a higher reaction yield than commercially available TS-1. The inventors hypothesize that in nickel-doped Ni@TS-1, some of the active sites of Ti are replaced by Ni, slightly reducing the catalytic activity of Ni@TS-1 compared to TS-1, thereby preventing the hydroxyl groups in DHA from being over-oxidized and nitrated during the catalytic process.

[0011] The ammonia source includes ammonia gas, ammonia water with a mass fraction of 25-28%, and hydrogen peroxide with a mass concentration of 30%. The type of ammonia source within the scope of this application does not affect the progress of this invention, nor does the concentration of ammonia water within the scope of this application affect the reaction.

[0012] Preferably, the preparation method of the nickel-doped Ni@TS-1 includes the following steps:

[0013] A1. Mix tetrapropylammonium hydroxide with water, then add tetraethyl orthosilicate dropwise, and obtain seed crystals through hydrolysis, crystallization, washing, and drying.

[0014] A2. Mix titanium dioxide, nickel oxide, and isopropanol to form a TiO2-NiO-isopropanol mixed solution; mix silicon dioxide and water to form a silica sol;

[0015] A3. Dissolve ethanolamine and tetrapropylammonium bromide in water, then add silica sol dropwise and stir; under vigorous stirring, add the TiO2-NiO-isopropanol mixed solution dropwise; then add the seed crystal, stir, age, crystallize, wash, dry, and calcine to obtain the nickel-doped Ni@TS-1.

[0016] More preferably, in step A1, the molar ratio of tetrapropylammonium hydroxide, water, and tetraethyl orthosilicate is 0.256:30:1;

[0017] In step A2, the molar ratio of titanium dioxide, nickel oxide, isopropanol, silicon dioxide, and water is 0.02:0.5:0.5:1:30;

[0018] In step A3, the molar ratio of ethanolamine, tetrapropylammonium bromide, water, and silicon dioxide is 0.5:0.1:15:1;

[0019] The mass ratio of the seed crystal to the silicon dioxide is 1:25.

[0020] Specifically, the mass ratio of the bio-based 1,3-dihydroxyacetone to the catalyst is (2-3):1.

[0021] Specifically, the molar ratio of the bio-based 1,3-dihydroxyacetone, hydrogen peroxide, and ammonia source is 1:(2.2-2.6):(1.05-1.3).

[0022] Specifically, the temperature of the oxidative nitrification reaction is 40-60℃, and the reaction time is 3-6h; preferably, the temperature of the oxidative nitrification reaction can be 40℃, 45℃, 50℃, 55℃ or 60℃, etc., and the reaction time can be 3h, 4h, 5h or 6h, etc., but is not limited to the values ​​listed above, and other unlisted values ​​within the above range are also applicable.

[0023] The oxidative nitration reaction also requires the addition of a solvent, which includes at least one of methanol, ethanol, acetonitrile, and water.

[0024] Specifically, the molar ratio of 1,3-dihydroxynitropropane, hydroxymethylating agent, and base is 1:(2-4):(0.1-0.3).

[0025] The hydroxymethylating agent includes one of a 37% aqueous formaldehyde solution and paraformaldehyde; the base includes potassium hydroxide, sodium hydroxide, sodium carbonate, and triethylamine.

[0026] Specifically, the temperature of the condensation reaction is 40-60℃, and the reaction time is 6-12h; preferably, the temperature of the oxidative nitration reaction can be 40℃, 45℃, 50℃, 55℃ or 60℃, etc., and the reaction time can be 6h, 7h, 8h, 9h, 10h, 11h or 12h, etc., but is not limited to the values ​​listed above, and other unlisted values ​​within the above range are also applicable.

[0027] Preferably, the condensation reaction further requires the addition of a solvent, which includes at least one of methanol, water, ethanol, and acetonitrile.

[0028] Specifically, the conditions for the hydrogenation reduction reaction are as follows: adding a hydrogenation catalyst, a pressure of 1.2-1.5 MPa, a reaction temperature of 30-40°C, and a reaction time of 2-3 h; preferably, the pressure can be 1.2 MPa, 1.3 MPa, 1.4 MPa, or 1.5 MPa, the reaction temperature can be 30°C, 31°C, 32°C, 33°C, 34°C, 35°C, 36°C, 37°C, 38°C, 39°C, or 40°C, and the reaction time can be 2 h, 2.1 h, 2.2 h, 2.3 h, 2.4 h, 2.5 h, 2.6 h, 2.7 h, 2.8 h, 2.9 h, or 3.0 h, but are not limited to the values ​​listed above. Other unlisted values ​​within the above range are also applicable.

[0029] Preferably, the mass ratio of 1,3-dihydroxynitropropane to the hydrogenation catalyst is 1:(0.1-0.2);

[0030] Preferably, the hydrogenation catalyst includes Raney nickel, palladium on carbon, Ni / SiO2, and Ni / Al2O3.

[0031] Compared with the prior art, the present invention provides a method for preparing bio-based tromethamine, which has the following characteristics:

[0032] Beneficial effects:

[0033] This invention develops a sustainable synthetic route based on bio-based feedstocks. Starting with renewable 1,3-dihydroxyacetone, which can be obtained through microbial fermentation, bio-based tromethamine is efficiently prepared via an optimized three-step process of oxidative nitration, condensation, and reduction. This route significantly improves reaction efficiency and selectivity, effectively reduces feedstock costs and environmental impact, and lays a solid foundation for the green and economical production of bio-based tromethamine. Detailed Implementation

[0034] To further illustrate the technical means and effects of the present invention, the following describes the technical solution of the present invention in conjunction with preferred embodiments of the present invention. However, the present invention is not limited to the scope of the embodiments.

[0035] Preparation example: Preparation of nickel-doped Ni@TS-1 includes the following steps,

[0036] A1. Dilute 5.2g of tetrapropylammonium hydroxide (203.36g) in 54g of deionized water, stir for 1 hour, then add 20.8g of tetraethyl orthosilicate (TEOS) (208.327g). Hydrolyze at room temperature for 8 hours until the solution is clear and transparent and no longer separates into layers. Then transfer the solution to a reaction vessel and statically crystallize in an oven at 170℃ for 24 hours. After crystallization, cool down, open the vessel, centrifuge, wash several times with deionized water and ethanol, and dry at 80℃ for 8 hours to obtain 68g of S-1 molecular sieve without template agent removal as seed crystals for later use.

[0037] A2. Mix 0.16g of titanium dioxide (79.87g), 3.73g of nickel oxide (74.69g), and 3g of isopropanol (60.1g) to form a TiO2-NiO-isopropanol mixed solution; mix 6g of silicon dioxide (60.08g) and 54g of water to form 60g of silica sol.

[0038] A3. Under stirring, 3.1 g of ethanolamine (61.08 g) and 2.67 g of tetrapropylammonium bromide (266.27 g) were dissolved sequentially in 27 g of deionized water. After hydrolysis by stirring for 0.5 h, the silica sol from step A2 was slowly added dropwise, and the mixture was stirred for 1 h. The TiO2-NiO-isopropanol mixed solution from step A2 was added dropwise under vigorous stirring, and the mixture was stirred for 1 h. Then, 0.24 g of seed crystals from step A1 (4.0 wt% relative to the total amount of silicon dioxide in the silica sol) were added, and the mixture was aged at room temperature for 12 h. The final sol was statically crystallized at 170 °C for 2 days, washed several times with deionized water and ethanol, dried at 80 °C for 8 h, and then calcined at 550 °C for 8 h to obtain 16 g of nickel-doped Ni@TS-1. This preparation was repeated multiple times for later use.

[0039] Example 1

[0040] This embodiment provides a method for preparing bio-based tromethamine, including the following steps:

[0041] S1. In a reaction flask, 9 g of 1,3-dihydroxyacetone (90.08 g, 0.1 mol) and 200 ml of methanol were added first, followed by 4 g of the catalyst Ni@TS-1 prepared in the preparation example. After mixing, the mixture was stirred and heated to 60 °C. Then, 27.2 g (34 g, 0.24 mol) of hydrogen peroxide (30%) and 7.56 g (17 g, 0.12 mol) of ammonia (27%) were added dropwise. After the addition was complete, the reaction was maintained at this temperature for 3 h, and the reaction was monitored by GC until the conversion of the starting material was complete. After the reaction was complete, 5 g of sodium thiosulfate was added to quench the hydrogen peroxide, and then methanol was removed by vacuum distillation. The aqueous layer was washed three times with 200 ml of ethyl acetate, and the organic solvent was removed by vacuum distillation, yielding 12.0 g of a white solid, 1,3-dihydroxynitropropane, with a reaction yield of 95%.

[0042] S2. In a reaction flask, first add 12.1g of 1,3-dihydroxynitropropane (120.08, 0.1mol), 100ml of methanol, then add 9.1g of paraformaldehyde (30.03, 0.3), and finally add 1.1g of potassium hydroxide (56.11). After mixing, stir and heat to 40℃, maintain the temperature for 12h, and monitor the reaction until the conversion of the raw materials is complete via GC. After the reaction is complete, add 3g of formic acid to the reaction solution to adjust the pH to neutral. Transfer the reaction solution to an autoclave, add 2.4g of Raney nickel, close the autoclave lid, purge with hydrogen three times, pressurize to 1.2MPa, and react at 40℃ for 3h. After cooling, open the autoclave, remove 70ml of methanol by vacuum distillation, and cool the remaining reaction solution to -5℃ to crystallize for 6h. After filtration, obtain 11.5g of white solid bio-based tromethamine, with a reaction yield of 95% and a purity of 99.7%.

[0043] Example 2

[0044] This embodiment provides a method for preparing bio-based tromethamine, which is basically the same as that in Example 1, except that in step S1, 4g of catalyst TS-1 (commercially available) is added, and a total of 9.4g of white solid 1,3-dihydroxynitropropane is finally obtained, with a reaction yield of 75% and a purity of 95%.

[0045] Example 3

[0046] This embodiment provides a method for preparing bio-based tromethamine, which is basically the same as that in Example 1, except that in step S1, 4.5g of catalyst Ni@TS-1 is added, and 12.0g of white solid 1,3-dihydroxynitropropane is finally obtained, with a reaction yield of 95% and a purity of 99.8%.

[0047] Example 4

[0048] This embodiment provides a method for preparing bio-based tromethamine, which is basically the same as that in Example 1, except that in step S1, 3g of catalyst Ni@TS-1 is added, and 11.6g of white solid 1,3-dihydroxynitropropane is finally obtained, with a reaction yield of 92% and a purity of 99.5%.

[0049] Example 5

[0050] This embodiment provides a method for preparing bio-based tromethamine, which is basically the same as that in Example 1, except that in step S1, 29.5g (34, 0.26mol) of hydrogen peroxide (30%) and 8.2g (0.13mol) of ammonia (27%) are added dropwise at the beginning, and finally 11.0g of white solid 1,3-dihydroxynitropropane is obtained, with a reaction yield of 91% and a purity of 99.2%.

[0051] Example 6

[0052] This embodiment provides a method for preparing bio-based tromethamine, which is basically the same as that in Example 1, except that in step S1, 23.0 g (34, 0.22 mol) of hydrogen peroxide (30%) and 6.6 g (0.105 mol) of ammonia (27%) are added dropwise at the beginning, and finally 10.6 g of white solid 1,3-dihydroxynitropropane is obtained, with a reaction yield of 88% and a purity of 99.0%.

[0053] Example 7

[0054] This embodiment provides a method for preparing bio-based tromethamine, which is basically the same as that in Example 1, except that in step S1, the temperature of the oxidative nitration reaction is 40°C and the reaction time is 6 hours, and finally 11.1 g of white solid 1,3-dihydroxynitropropane is obtained, with a reaction yield of 88% and a purity of 99.1%.

[0055] Example 8

[0056] This embodiment provides a method for preparing bio-based tromethamine, which is basically the same as that in Example 1, except that in step S1, the temperature of the oxidative nitration reaction is 50°C and the reaction time is 4.5 h, and finally 11.6 g of white solid 1,3-dihydroxynitropropane is obtained, with a reaction yield of 92% and a purity of 99.5%.

[0057] Example 9

[0058] This embodiment provides a method for preparing bio-based tromethamine, which is basically the same as that in Example 1, except that: S1, in a reaction flask, 9g of 1,3-dihydroxyacetone (90.08g) and 200ml of acetonitrile are first added, followed by 4g of catalyst Ni@TS-1. After mixing, the mixture is stirred and heated to 50°C. Then, 27.2g (34, 0.24mol) of hydrogen peroxide (30%) and 8.16g (17, 0.12mol) of ammonia (25%) are added dropwise. After the addition is complete, the reaction is maintained at this temperature for 4 hours, and the reaction is monitored by GC until the conversion of the raw materials is complete. After the reaction is complete, 5g of sodium thiosulfate is added to quench the hydrogen peroxide, and then methanol is removed by vacuum distillation. The aqueous layer is washed three times with 200ml of ethyl acetate, and the organic solvent is removed by vacuum distillation, yielding 11.1g of white solid 1,3-dihydroxynitropropane. The reaction yield is 92%, and the purity is 99.4%.

[0059] Example 10

[0060] This embodiment provides a method for preparing bio-based tromethamine, which is basically the same as that in Example 1, except that in step S2, 6.0g of paraformaldehyde (30.03g) is added, and after filtration, 11.3g of white solid bio-based tromethamine is obtained, with a reaction yield of 93% and a purity of 99.5%.

[0061] Example 11

[0062] This embodiment provides a method for preparing bio-based tromethamine, which is basically the same as that in Example 1, except that in step S2, 12.0g of paraformaldehyde (30.03g) is added, and after filtration, 11.5g of white solid bio-based tromethamine is obtained, with a reaction yield of 95% and a purity of 99.7%.

[0063] Example 12

[0064] This embodiment provides a method for preparing bio-based tromethamine, which is basically the same as that in Example 1, except that in step S2, 0.56g of potassium hydroxide (56.11, 0.01mol) is added, and after filtration, 11.1g of white solid bio-based tromethamine is obtained, with a reaction yield of 92% and a purity of 99.5%.

[0065] Example 13

[0066] This embodiment provides a method for preparing bio-based tromethamine, which is basically the same as that in Example 1, except that in step S2, 1.7g of potassium hydroxide (56.11, 0.03mol) is added, and after filtration, 11.5g of white solid bio-based tromethamine is obtained, with a reaction yield of 95% and a purity of 99.8%.

[0067] Example 14

[0068] This embodiment provides a method for preparing bio-based tromethamine, which is basically the same as that in Example 1, except that in step S2, the condensation reaction temperature is 50°C and the reaction time is 9 hours. After filtration, a total of 11.4 g of white solid bio-based tromethamine is obtained, with a reaction yield of 94% and a purity of 99.5%.

[0069] Example 15

[0070] This embodiment provides a method for preparing bio-based tromethamine, which is basically the same as that in Example 1, except that in step S2, the condensation reaction temperature is 60°C and the reaction time is 5 hours. After filtration, a total of 11.1 g of white solid bio-based tromethamine is obtained, with a reaction yield of 92% and a purity of 99.4%.

[0071] Example 16

[0072] This embodiment provides a method for preparing bio-based tromethamine, which is basically the same as that in Example 1. The difference is that in step S2, 1.2g of Raney nickel is added, the mixture is replaced with hydrogen three times, and then pressurized to 1.5MPa. The mixture is reacted at 30°C for 3 hours. Finally, after filtration, 10.3g of white solid bio-based tromethamine is obtained, with a reaction yield of 85% and a purity of 96%.

[0073] Example 17

[0074] This embodiment provides a method for preparing bio-based tromethamine, which is basically the same as that in Example 1, except that in step S2, 2.4g of Raney nickel is added, the mixture is replaced with hydrogen three times, pressurized to 1.4MPa, and reacted at 40°C for 2.5h. After filtration, a total of 11.0g of white solid bio-based tromethamine is obtained, with a reaction yield of 91% and a purity of 99.3%.

[0075] Example 18

[0076] This embodiment provides a method for preparing bio-based tromethamine, which is basically the same as that in Example 1, except that in step S2, 2.4g of palladium on carbon is added, and after filtration, a total of 11.3g of white solid bio-based tromethamine is obtained, with a reaction yield of 93% and a purity of 99.4%.

[0077] Comparative Example 1

[0078] This comparative example provides a method for preparing bio-based tromethamine, which is basically the same as that in Example 1. The difference is that in step S1, 4g of titanium-silicon molecular sieve Ti-MWW catalyst is used, resulting in a low reaction yield and the reaction being almost impossible to proceed.

[0079] Comparative Example 2

[0080] This comparative example provides a method for preparing bio-based tromethamine, which is basically the same as that in Example 1, except that in step S1, 2g of catalyst Ni@TS-1 is added, and a total of 8.6g of white solid 1,3-dihydroxynitropropane is finally obtained, with a reaction yield of 68% and a purity of 70%.

[0081] Comparative Example 3

[0082] This comparative example provides a method for preparing bio-based tromethamine, which is basically the same as that in Example 1, except that in step S1, 6g of catalyst Ni@TS-1 is added, ultimately yielding 12.0g of white solid 1,3-dihydroxynitropropane, with a reaction yield of 95% and a purity of 96%. Although the yield of this comparative example is acceptable, it results in a waste of catalyst.

[0083] Comparative Example 4

[0084] This comparative example provides a method for preparing bio-based tromethamine, which is basically the same as that in Example 1, except that in step S1, 34g of hydrogen peroxide (30%) (34, 0.3mol) and 7.56g of ammonia (27%) (17, 0.12mol) are added dropwise at the beginning, and finally 8.7g of white solid 1,3-dihydroxynitropropane are obtained, with a reaction yield of 69% and a purity of 66%.

[0085] Comparative Example 5

[0086] This comparative example provides a method for preparing bio-based tromethamine, which is basically the same as that in Example 1, except that in step S1, 27.2 g (34, 0.24 mol) of hydrogen peroxide (30%) and 9.44 g (17, 0.15 mol) of ammonia (27%) are added dropwise at the beginning, and finally 8.2 g of white solid 1,3-dihydroxynitropropane is obtained, with a reaction yield of 65% and a purity of 59%.

[0087] Comparative Example 6

[0088] This comparative example provides a method for preparing bio-based tromethamine, which is basically the same as that in Example 1, except that in step S1, the temperature of the oxidative nitration reaction is 75°C and the reaction time is 3 hours, and a total of 10.6 g of white solid 1,3-dihydroxynitropropane is finally obtained, with a reaction yield of 84% and a purity of 82%.

[0089] Comparative Example 7

[0090] This comparative example provides a method for preparing bio-based tromethamine, which is basically the same as that in Example 1, except that in step S1, the temperature of the oxidative nitration reaction is 30°C and the reaction time is 6 hours, and finally 4.4 g of white solid 1,3-dihydroxynitropropane is obtained, with a reaction yield of 35%.

[0091] Comparative Example 8

[0092] This comparative example provides a method for preparing bio-based tromethamine, which is basically the same as that in Example 1, except that in step S2, 3.0 g of paraformaldehyde (30.03 g) is added, and finally 1.1 g of potassium hydroxide (56.11 g, 0.14 mol) is added to obtain 6.3 g of white solid 1,3-dihydroxynitropropane, with a reaction yield of 50% and a purity of 66%.

[0093] Comparative Example 9

[0094] This comparative example provides a method for preparing bio-based tromethamine, which is basically the same as that in Example 1, except that potassium hydroxide is not added in step S2, otherwise the reaction can hardly proceed.

[0095] Comparative Example 10

[0096] This comparative example provides a method for preparing bio-based tromethamine, which is basically the same as that in Example 1, except that in step S2, the condensation reaction temperature is 70°C and the reaction time is 5 hours. After filtration, a total of 8.5 g of white solid bio-based tromethamine is obtained, with a reaction yield of 70% and a purity of 76%.

[0097] The applicant declares that this invention illustrates a method for preparing a bio-based tromethamine through the above embodiments, but this invention is not limited to the above embodiments, that is, it does not mean that this invention must rely on the above embodiments to be implemented. Those skilled in the art should understand that any improvements to this invention, equivalent substitutions of the raw materials for the product of this invention, addition of auxiliary components, and selection of specific methods, etc., all fall within the protection scope and disclosure scope of this invention.

[0098] The preferred embodiments of the present invention have been described in detail above. However, the present invention is not limited to the specific details in the above embodiments. Within the scope of the technical concept of the present invention, various simple modifications can be made to the technical solution of the present invention, and these simple modifications all fall within the protection scope of the present invention.

[0099] It should also be noted that the various specific technical features described in the above specific embodiments can be combined in any suitable manner without contradiction. In order to avoid unnecessary repetition, the present invention will not describe the various possible combinations separately.

Claims

1. A method for preparing bio-based tromethamine, characterized in that, Includes the following steps, S1. Using bio-based 1,3-dihydroxyacetone, hydrogen peroxide, and ammonia source as raw materials, 1,3-dihydroxynitropropane is obtained by oxidative nitration under the action of a catalyst. S2. A hydroxymethylating agent is added to 1,3-dihydroxynitropropane, and a condensation reaction occurs under alkaline conditions. Then, the mixture is hydrogenated and reduced to obtain bio-based tromethamine.

2. The preparation method according to claim 1, characterized in that, The catalyst includes TS-1 and nickel-doped Ni@TS-1, and the ammonia source includes ammonia gas, ammonia water with a mass fraction of 25-28%, and hydrogen peroxide with a mass concentration of 30%.

3. The preparation method according to claim 2, characterized in that, The preparation method of the nickel-doped Ni@TS-1 includes the following steps: A1. Mix tetrapropylammonium hydroxide with water, then add tetraethyl orthosilicate dropwise, and obtain seed crystals through hydrolysis, crystallization, washing, and drying. A2. Mix titanium dioxide, nickel oxide, and isopropanol to form a TiO2-NiO-isopropanol mixed solution; mix silicon dioxide and water to form a silica sol; A3. Dissolve ethanolamine and tetrapropylammonium bromide in water, then add silica sol dropwise and stir; under vigorous stirring, add the TiO2-NiO-isopropanol mixed solution dropwise; then add the seed crystal, stir, age, crystallize, wash, dry, and calcine to obtain the nickel-doped Ni@TS-1.

4. The preparation method according to claim 3, characterized in that: In step A1, the molar ratio of tetrapropylammonium hydroxide, water, and tetraethyl orthosilicate is 0.256:30:1; In step A2, the molar ratio of titanium dioxide, nickel oxide, isopropanol, silicon dioxide, and water is 0.02:0.5:0.5:1:30; In step A3, the molar ratio of ethanolamine, tetrapropylammonium bromide, water, and silicon dioxide is 0.5:0.1:15:1; The mass ratio of the seed crystal to the silicon dioxide is 1:

25.

5. The preparation method according to claim 1, characterized in that, The mass ratio of the bio-based 1,3-dihydroxyacetone to the catalyst is (2-3):

1.

6. The preparation method according to claim 1, characterized in that, The molar ratio of the bio-based 1,3-dihydroxyacetone, hydrogen peroxide, and ammonia source is 1:(2.2-2.6):(1.05-1.3).

7. The preparation method according to claim 1, characterized in that, The oxidative nitration reaction is carried out at a temperature of 40-60℃ for 3-6 hours. The oxidative nitration reaction also requires the addition of a solvent, which includes at least one of methanol, ethanol, acetonitrile, and water.

8. The preparation method according to claim 1, characterized in that, The molar ratio of 1,3-dihydroxynitropropane, hydroxymethylating agent, and base is 1:(2-4):(0.1-0.3). The hydroxymethylating agent includes one of a 37% aqueous formaldehyde solution and paraformaldehyde; the base includes potassium hydroxide, sodium hydroxide, sodium carbonate, and triethylamine.

9. The preparation method according to claim 1, characterized in that, The condensation reaction is carried out at a temperature of 40-60℃ for 6-12 hours. Preferably, the condensation reaction further requires the addition of a solvent, which includes at least one of methanol, water, ethanol, and acetonitrile.

10. The preparation method according to claim 1, characterized in that, The conditions for the hydrogenation reduction reaction are as follows: hydrogenation catalyst is added, pressure is 1.2-1.5 MPa, reaction temperature is 30-40℃, and reaction time is 2-3 h. Preferably, the mass ratio of 1,3-dihydroxynitropropane to the hydrogenation catalyst is 1:(0.1-0.2); Preferably, the hydrogenation catalyst includes Raney nickel, palladium on carbon, Ni / SiO2, and Ni / Al2O3.