Catalyst for preparing acetyl n-propanol through catalytic oxidation of 2-methyltetrahydrofuran and preparation method
By using an inexpensive vanadium-based catalyst to catalyze the oxidation of 2-methyltetrahydrofuran with molecular oxygen to produce acetylacetonol, the high cost problem caused by precious metal catalysts in existing processes is solved, achieving efficient and environmentally friendly production of acetylacetonol with potential for industrial application.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- ZHENGZHOU UNIV
- Filing Date
- 2025-12-30
- Publication Date
- 2026-04-17
AI Technical Summary
Existing processes for preparing acetylacetonol use precious metal catalysts, resulting in high costs, low efficiency, and significant challenges in environmental remediation. Traditional routes also suffer from low product yields and severe loss of precious metals.
A catalyst was prepared by using inexpensive vanadium compounds as the main active component, supplemented with oxalic acid as a pore-forming agent, and adding non-precious metal additives such as iron and silicon. This catalyst is used to catalyze the oxidation of 2-methyltetrahydrofuran to acetylpropanol by molecular oxygen, thus avoiding the use of precious metal catalysts. Combined with mild reaction conditions (60℃, 1.5 MPa O2, 3 h), a high-efficiency conversion is achieved.
It achieves highly selective and efficient conversion of 2-methyltetrahydrofuran to acetyl-n-propanol, with good catalyst reusability, reduced production costs, conforms to green chemistry principles, reduces waste liquid discharge, and has prospects for industrial application.
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Figure CN121869340A_ABST
Abstract
Description
Technical Field
[0001] This invention relates to the field of catalyst technology, specifically to a catalyst and preparation method for the catalytic oxidation of 2-methyltetrahydrofuran to prepare acetyl-n-propanol. Background Technology
[0002] Acetylacetonol is an important organic intermediate widely used in the synthesis of pharmaceuticals and pesticides. It is a key intermediate in the synthesis of the antimalarial drug chloroquine, the antibacterial drug quinolone, vitamin B1, and the fungicides pyraclostrobin and cyclophosphamide. Its downstream products, cyclopropyl methyl ketone and 5-chloro-2-pentanone, are key intermediates in the anti-AIDS drugs efavirenz and irradin, respectively. Currently, acetylacetonol is industrially produced using 2-methylfuran from biomass as a raw material, via a one-pot hydrogenation hydrolysis under acidic conditions with a Pd / C (10wt% Pd) catalyst. In this route, the weight ratio of the raw material to dilute hydrochloric acid (10wt%) is approximately 2:1, the catalyst dosage is 0.5 wt%, the reaction time is 30°C for 20–28 hours, and the molar yield of the product is approximately 70%. Pd / C catalysts are expensive, deactivate rapidly and are easily lost (they can be reused approximately 10 times), require long reaction times, and generate large amounts of low-concentration waste acid and wastewater. This results in high production costs, low efficiency, and significant environmental challenges associated with this route. Therefore, developing a green reaction route for the biomass-to-acetylpropanol production that does not rely on precious metal catalysts is essential.
[0004] Hollmann et al. used *P. furiosus* biocatalyst to reduce levulinic acid to acetylacetonol. The reaction was carried out in a sodium phosphate buffer solution at pH 6.5, under 0.5 MPa hydrogen pressure, at 40°C for 24 hours, with a maximum yield of 51%. Professor Guo Chun et al. from Shenyang Pharmaceutical University used ethyl levulinate as a raw material, protected the carbonyl group with a ketal, and then reduced it with sodium borohydride to obtain acetylacetonol, with a maximum yield of 85%. Park's research group used 1,4-pentanediol as a raw material, the Ru complex (η5-Ph4C4COH)(CO)2RuCl as a catalyst, and chloroform as both oxidant and solvent. The reaction was carried out at 90°C for 8 hours, resulting in complete conversion of the raw material and a product yield of approximately 50%. The heteropoly acid Na4H3[SiW9Al3(H2O)3O] was also used. 37 Using 12H₂O as a catalyst and 30% H₂O₂ as an oxidant, acetylacetonate was prepared by oxidizing 1,4-pentanediol at 90℃ for 5 hours, with a product yield of 62%. The reaction of furfural hydrogenation to acetylacetonate was studied under continuous process conditions using Pd-TiO₂ / C as a catalyst at a reaction temperature of 180℃ and a space velocity of 134 g·Lcat. −1 ·h −1Under the specified conditions, the selectivity of the target product was 39%. Using Ru / HBeta as a catalyst, furfural can be directly hydrogenated to acetylacetonol in aqueous solution, with a maximum product yield of 81%. However, the above reaction route still suffers from drawbacks such as low product yield, the need for precious metal catalysts, or difficulties in separating reaction products, resulting in high production costs and making it difficult to replace existing production processes.
[0005] 2-Methyltetrahydrofuran is a biomass-derived chemical, primarily used as a solvent and intermediate in chemical reactions. Currently, industrial production of 2-methyltetrahydrofuran involves hydrogenation of 2-methylfuran under Raney nickel catalysis; this reaction occurs at 150°C, with a product yield greater than 90%. The required raw material, 2-methylfuran, is prepared by hydrogenation of furfural, a bulk biomass chemical, over a copper-based catalyst at 190°C, with a product yield ≥98%. Using readily available 2-methyltetrahydrofuran as a raw material and molecular oxygen as an oxidant to oxidize and prepare the target product, acetylacetonol, represents a novel reaction route (as shown in the diagram below). This route does not use precious metal catalysts; therefore, the core challenge in achieving this design is the preparation of highly active and selective catalysts.
[0006] Summary of the Invention
[0007] To address the high cost of existing processes for preparing acetylacetonol due to the use of precious metal catalysts, this invention provides a catalyst and preparation method for the catalytic oxidation of 2-methyltetrahydrofuran to acetylacetonol. The catalyst prepared by this invention is a catalyst for the catalytic oxidation of 2-methyltetrahydrofuran to acetylacetonol using molecular oxygen, thus realizing a new route for the preparation of acetylacetonol.
[0008] To achieve the above objectives, the technical solution adopted by the present invention is as follows:
[0009] A method for preparing a catalyst for the catalytic oxidation of 2-methyltetrahydrofuran to acetylpropanol, the method comprising: dissolving the main component of the catalyst, a vanadium-containing compound, and the pore-forming agent oxalic acid in deionized water; heating the solution to hydrolyze it, so that the water evaporates completely to obtain a solid; and calcining the solid in an air atmosphere to obtain the catalyst.
[0010] As a preferred embodiment of the present invention, the vanadium-containing compound includes, but is not limited to, one of: ammonium metavanadate, vanadium oxysulfate, and vanadium oxychloride.
[0011] As a preferred embodiment of the present invention, the molar ratio of the vanadium-containing compound to oxalic acid is 1:1 to 1:3.
[0012] As a preferred embodiment of the present invention, the hydrolysis temperature is 80~120℃ and the hydrolysis time is 3~15 h.
[0013] As a preferred embodiment of the present invention, the calcination temperature is 300-500℃ and the calcination time is 3-8 h.
[0014] As a preferred embodiment of the present invention, iron-containing compounds and / or silicon sources as structural additives are also added to the deionized water.
[0015] As a preferred embodiment of the present invention, the iron-containing compound includes, but is not limited to, FeCl3.
[0016] As a preferred embodiment of the present invention, in the hydrolyzed solution, nFe : nV = 1 : 10.
[0017] As a preferred embodiment of the present invention, the silicon source is tetraethyl orthosilicate.
[0018] As a preferred embodiment of the present invention, in the hydrolyzed solution, nSi : nV = 1 : 20.
[0019] As a preferred embodiment of the present invention, the catalyst prepared by the preparation method is composed of vanadium oxide, additives, and structural additives.
[0020] As a preferred embodiment of the present invention, the vanadium content in the catalyst is 0.5~95 wt%.
[0021] As a preferred embodiment of the present invention, the catalyst contains 0.5 to 8 wt% iron.
[0022] As a preferred embodiment of the present invention, the silicon content in the catalyst is 0.5~8 wt%.
[0023] As a preferred embodiment of the present invention, the catalyst prepared by the preparation method is used for the catalytic oxidation of 2-methyltetrahydrofuran to prepare acetylacetonol.
[0024] As a preferred embodiment of the present invention, the mass ratio of the catalyst used in the catalytic reaction to the volume ratio of the reactant 2-methyltetrahydrofuran is 0.01 g·mL. -1 The pressure of O2 is 1.5 MPa.
[0025] As a preferred embodiment of the present invention, the temperature of the catalytic reaction is 60°C and the time of the catalytic reaction is 3 h.
[0026] As a preferred embodiment of the present invention, tert-butyl hydroperoxide is added to the reactant 2-methyltetrahydrofuran during the catalytic reaction, with a molar ratio of 1:50 to the reactant 2-methyltetrahydrofuran.
[0027] Compared with the prior art, the beneficial effects of the present invention are as follows:
[0028] 1. The catalyst prepared by this invention does not contain any precious metals (such as Pd, Ru, etc.), uses inexpensive vanadium compounds as the main active component, supplemented by oxalic acid as a pore-forming agent, and introduces non-precious metal additives such as iron and silicon. The raw materials are widely available and inexpensive, which greatly reduces the cost of catalyst preparation.
[0029] 2. Under mild conditions (60℃, 1.5 MPa O2, 3 h), the catalyst of the present invention can achieve efficient conversion of 2-methyltetrahydrofuran (maximum conversion rate 65%) and selectively generate acetylpropanol (maximum yield 36%), exhibiting excellent catalytic activity and selectivity.
[0030] 3. The catalyst prepared by this invention retains its catalytic activity and product yield essentially unchanged (change <3%) after being reused 6 times, demonstrating good structural stability and regeneration potential, and has prospects for industrial application.
[0031] 4. Using biomass derivative 2-methyltetrahydrofuran as a raw material and combining molecular oxygen oxidation, a novel synthetic route for acetylacetonol was constructed, eliminating the dependence on precious metal catalysts and representing a significant technological breakthrough.
[0032] 5. This invention uses molecular oxygen as a green oxidant and does not use any solvents during the reaction process, thus avoiding the generation of large amounts of acidic waste liquid and wastewater in traditional processes. It conforms to the principles of green chemistry and has good environmental compatibility. Attached Figure Description
[0033] Figure 1 V2O5-300 of Example 1 and V2O of Example 2 5- XRD patterns of V2O5-500 in Example 400 and Example 3.
[0034] Figure 2 V2O5-300 of Example 1 and V2O of Example 2 5- Scanning electron microscope images of V2O5-500 in Example 400 and Example 3, (a) V2O5-300, (b) V2O5-400, (c) V2O5-500. Detailed Implementation
[0035] The technical solution and effects of the present invention will be further described below with reference to the accompanying drawings and specific embodiments, but the scope of protection of the present invention is not limited thereto.
[0036] Example 1
[0037] The catalyst preparation process in this embodiment is as follows:
[0038] Ammonium metavanadate (NH4VO3) and oxalic acid (H2C2O4·2H2O) (molar ratio 1:3) were dissolved in deionized water and stirred at room temperature for 10 min. The solution was then heated at 120 °C to evaporate all the water, yielding a solid. The solid sample was then calcined in a muffle furnace at 300 °C for 4 h to obtain the V2O5-300 sample.
[0039] See attached XRD pattern for sample. Figure 1 The prepared V₂O₅-300 is orthorhombic. The morphology of the sample is shown in the appendix. Figure 2 It is composed of nanosheets with a size of tens of nanometers aggregated together.
[0040] The process of using the prepared catalyst to catalyze the oxidation of 2-methyltetrahydrofuran to acetylacetonol is as follows:
[0041] The catalyst and reactant 2-methyltetrahydrofuran were sequentially added to a high-pressure reactor and sealed (the mass ratio of the catalyst to the volume of the reactant 2-methyltetrahydrofuran was 0.01 g·mL). -1 Next, O2 was introduced to 1.5 MPa. The reaction was carried out at 60°C for 3 h.
[0042] The conversion rate of 2-methyltetrahydrofuran was 61%, and the yield of acetylacetonol was 31% (both yields were carbon yields).
[0043] Example 2
[0044] The uncalcined solid sample obtained in Example 1 was calcined in a muffle furnace at 400°C for 4 h to obtain V2O5-400.
[0045] See attached XRD pattern for sample. Figure 1 The prepared V₂O₅-400 is orthorhombic. The morphology of the sample is shown in the appendix. Figure 2 They are composed of aggregates of nanosheets, ranging in size from tens to hundreds of nanometers.
[0046] The catalyst prepared was used for the catalytic oxidation of 2-methyltetrahydrofuran to prepare acetylacetonol in the same process as in Example 1.
[0047] The conversion rate of 2-methyltetrahydrofuran was 53%, and the yield of acetylacetonol was 23%.
[0048] Example 3
[0049] The uncalcined solid sample obtained in Example 1 was calcined in a muffle furnace at 500°C for 4 h to obtain V2O5-500.
[0050] See attached XRD pattern for sample. Figure 1 The prepared V₂O₅-500 is orthorhombic. The morphology of the sample is shown in the appendix. Figure 2It is composed of agglomerates of nanosheets with a size of several hundred nanometers. As the calcination temperature increases, the size of the nanosheets increases, and the catalytic performance decreases.
[0051] The catalyst prepared was used for the catalytic oxidation of 2-methyltetrahydrofuran to prepare acetylacetonol in the same process as in Example 1.
[0052] The conversion rate of 2-methyltetrahydrofuran was 53%, and the yield of acetylacetonol was 20%.
[0053] Example 4
[0054] Except for the molar ratio of ammonium metavanadate to oxalic acid being 1:2, the other steps are the same as in Example 1.
[0055] The conversion rate of 2-methyltetrahydrofuran was 49%, and the yield of acetylacetonol was 23%.
[0056] Example 5
[0057] The catalyst preparation process in this embodiment is as follows:
[0058] Ammonium metavanadate (NH4VO3) and oxalic acid (H2C2O4·2H2O) (molar ratio 1:3) were dissolved in deionized water and stirred at room temperature for 10 min. Then, an aqueous solution of FeCl3 (nFe:nV = 1:10) was added. The solution was heated to 120 °C to completely evaporate the water, yielding a solid. The solid sample was then calcined in a muffle furnace at 500 °C for 4 h to obtain FeO. x -V2O5 sample.
[0059] The catalyst prepared was used for the catalytic oxidation of 2-methyltetrahydrofuran to prepare acetylacetonol in the same process as in Example 1.
[0060] The conversion rate of 2-methyltetrahydrofuran was 65%, and the yield of acetylacetonol was 35%.
[0061] Example 6
[0062] The catalyst preparation process in this embodiment is as follows:
[0063] Ammonium metavanadate (NH4VO3) and oxalic acid (H2C2O4·2H2O) (molar ratio 1:3) were dissolved in deionized water and stirred at room temperature for 10 min. Then, tetraethyl orthosilicate (nSi:nV = 1:20) was added. The solution was heated to 120 °C to completely evaporate the water, yielding a solid. The solid sample was then calcined in a muffle furnace at 500 °C for 4 h to obtain SiO2. x -V2O5 sample.
[0064] The catalyst prepared was used for the catalytic oxidation of 2-methyltetrahydrofuran to prepare acetylacetonol in the same process as in Example 1.
[0065] The conversion rate of 2-methyltetrahydrofuran was 55%, and the yield of acetylacetonol was 29%.
[0066] Example 7
[0067] The catalyst preparation process in this embodiment is as follows:
[0068] Ammonium metavanadate (NH4VO3) and oxalic acid (H2C2O4·2H2O) (molar ratio 1:3) were dissolved in deionized water and stirred at room temperature for 10 min. Then, FeCl3 aqueous solution and ethyl silicate (nFe:nSi:nV = 2:1:20) were added sequentially. The solution was heated at 120 °C to completely evaporate the water, yielding a solid. The solid sample was then calcined in a muffle furnace at 500 °C for 4 h to obtain FeO. x -SiO2-V2O5 sample.
[0069] The catalyst prepared was used for the catalytic oxidation of 2-methyltetrahydrofuran to prepare acetylacetonol in the same process as in Example 1.
[0070] The conversion rate of 2-methyltetrahydrofuran was 61%, and the yield of acetylacetonol was 36%.
[0071] Compared with Examples 5-7, the addition of the additive helps to improve the activity and selectivity of the catalyst.
[0072] Example 8
[0073] In Example 7, ammonium metavanadate was replaced with vanadium oxysulfate, while other conditions remained unchanged.
[0074] The conversion rate of 2-methyltetrahydrofuran was 56%, and the yield of acetylacetonol was 28%.
[0075] Example 9
[0076] In Example 7, ammonium metavanadate was replaced with vanadium oxychloride, while other conditions remained unchanged.
[0077] The conversion rate of 2-methyltetrahydrofuran was 53%, and the yield of acetylacetonol was 26%.
[0078] Example 10
[0079] Other conditions were the same as in Example 1, except that the temperature of the catalytic oxidation reaction was 40°C.
[0080] The conversion rate of 2-methyltetrahydrofuran was 35%, and the yield of acetylacetonol was 19%.
[0081] Example 11
[0082] Tert-butyl hydroperoxide t-BuOOH (nt-BuOOH : n2-MTHF = 2 : 100) was added to the reactants of the oxidation reaction, and other conditions were the same as in Example 1.
[0083] The conversion rate of 2-methyltetrahydrofuran was 65%, and the yield of acetylacetonol was 35%.
[0084] Example 12
[0085] The catalyst after the reaction in Example 7 was centrifuged, dried, and used in the next reaction. After being reused 6 times, the conversion rate of the reactants and the yield of the products changed by less than 3%.
[0086] Although embodiments of the invention have been shown and described, it will be understood by those skilled in the art that various changes, modifications, substitutions and alterations can be made to these embodiments without departing from the principles and spirit of the invention, the scope of which is defined by the appended claims and their equivalents.
Claims
1. A method for preparing a catalyst for catalytic oxidation of 2-methyltetrahydrofuran to produce acetonopropyl alcohol, characterized by, The specific preparation method involves dissolving the main component of the catalyst, a vanadium-containing compound, and the pore-forming agent, oxalic acid, in deionized water. The solution is heated and hydrolyzed to completely evaporate the water, yielding a solid. The solid is then calcined in air to obtain the catalyst.
2. The production method according to claim 1, characterized by, The vanadium-containing compounds include, but are not limited to, one of: ammonium metavanadate, vanadium oxysulfate, and vanadium oxychloride.
3. The production method according to claim 1, characterized by, The molar ratio of the vanadium-containing compound to oxalic acid is 1:1-1:
3.
4. The production method according to claim 1, characterized by, The roasting temperature is 300-500℃, and the roasting time is 3-8 h.
5. The production method according to any one of claims 1 to 4, characterized by, Iron compounds and / or silicon sources, structural additives, are also added to deionized water.
6. The production method according to claim 5, characterized by, The iron-containing compound is FeCl3, and in the hydrolyzed solution, nFe : nV = 1 :
10.
7. The production method according to claim 5, characterized by, The silicon source is tetraethyl orthosilicate, and in the hydrolyzed solution, nSi : nV = 1 :
20.
8. The production method according to any one of claims 5 to 7, characterized by, The catalyst prepared by the method described above is used to catalyze the oxidation of 2-methyltetrahydrofuran with molecular oxygen to prepare acetylpropanol.
9. The production method according to claim 8, characterized by, The mass ratio of the catalyst used in the catalytic reaction to the volume of the reactant 2-methyltetrahydrofuran was 0.01 g·mL. -1 The pressure of O2 is 1.5 MPa.
10. The production method according to claim 8, characterized by, During the catalytic reaction, tert-butyl hydroperoxide is added to the reactant 2-methyltetrahydrofuran at a molar ratio of 1:50.