Catalyst for preparing aviation fuel intermediate by catalyzing condensation reaction of furfural and acetone as well as preparation method and application of catalyst

Abstract

The invention discloses a catalyst for preparing an aviation fuel intermediate by catalyzing a condensation reaction of furfural and acetone and a preparation method and application thereof, the structure of the catalyst is X a / MgO-MCM-41b, X is at least one of potassium, sodium or calcium; a represents the mass percentage of X in the total mass of the catalyst, and the value range is 8-12%; mgO-MCM-41 is a mesoporous molecular sieve carrier, and the pore diameter of the MgO-MCM-41 is 2.8 nm to 3.6 nm; and b represents the molar ratio of Si to Mg in the catalyst, and the value is 25: 1-45: 1. The method is mild in reaction condition, excellent in catalytic activity and high in yield and selectivity. The reaction can be completed at the temperature of 30-50 DEG C, the conversion rate of acetone can reach 100%, a product which is difurfurylideneacetone as a dicondensation product can be obtained, and the yield can reach 99.8% or above.

Description

Technical Field

[0001] The invention relates to a catalyst for catalyzing the condensation reaction of furfural and acetone to prepare an aviation fuel intermediate, a preparation method and application thereof, and belongs to the technical field of organic synthesis and green catalysis. Background Art

[0002] With the rapid development of the global air transport industry, annual aviation fuel consumption exceeded 350 million tons in 2023, with fossil fuels accounting for over 98%. However, traditional fossil energy reserves are declining at a rate of 4.3% per year. Biomass energy, as a high-value renewable energy source, offers significant energy conversion potential and environmental benefits. Biomass-based sustainable aviation fuel is considered a key solution.

[0003] Lignocellulosic biomass, including woody and herbaceous materials, agricultural waste, and municipal organic waste, is a globally widespread, renewable, and carbon-neutral resource. Lignocellulosic biomass can be converted into a range of high-value-added chemicals, such as furfural, 5-hydroxymethylfurfural, levulinic acid, and methyl glycolate, through physical, chemical, and biological methods. Furfural, derived from the catalytic hydrolysis of hemicellulose and listed as one of the FDA's Top 30 bio-based chemicals, offers high energy density and carbon conversion, making it an ideal precursor for alternative aviation fuels. Catalysis, by regulating the selectivity and conversion of furfural, is a key driver of the technological and economic viability of producing sustainable aviation fuel from lignocellulosic biomass. Traditional homogeneous catalysts offer advantages such as high activity and efficiency, but they also pose challenges such as equipment corrosion and high wastewater treatment costs. Heterogeneous catalysts, through multiscale structural manipulation and interface engineering, offer significant advantages in green chemistry and the circular economy. Therefore, the research and application of heterogeneous catalysts in the catalytic conversion of furfural is of great significance.

[0004] Patent CN119549148A prepared a Fe3O4@FeMgAl-LDH magnetic catalyst, which was used to catalyze the condensation reaction of furfural and acetone. The reaction was carried out at 160°C for 2 hours, and the total yield of the monocondensation product FAc and the dicondensation product F2Ac was above 99.8%. Patent CN109759046A prepared a supported solid base catalyst, which was used to catalyze the condensation reaction of furfural and acetone. The reaction was carried out at 80°C for 1 hour, and the yield of the dicondensation product was 42.3%. The above-mentioned catalytic system has problems such as harsh reaction conditions, low yield of the dicondensation product, and insufficient catalyst recycling performance. Therefore, there is an urgent need to develop a new catalyst that can have high selectivity, economy, environmental friendliness and excellent recyclability under mild reaction conditions, which is of great significance for improving the sustainability of the catalytic process. Summary of the Invention

[0005] The present invention addresses the technical deficiencies of existing catalytic systems in the condensation reaction of furfural and acetone to produce aviation fuel intermediates. It provides a catalyst for catalyzing the condensation reaction of furfural and acetone to produce aviation fuel intermediates, a preparation method thereof, and its application. Furthermore, the present invention optimizes the synthesis method of difurfurylideneacetone, eliminating the need for the addition of excess acetone and reaction solvent, thereby reducing production costs and significantly improving carbon conversion efficiency. Furthermore, the present invention significantly reduces the reaction temperature, shortens the reaction time, reduces energy consumption, and improves reaction efficiency.

[0006] In order to solve the above technical problems, the technical solutions adopted by the present invention are as follows:

[0007] A catalyst for catalyzing the condensation reaction of furfural and acetone to prepare an aviation fuel intermediate has a structure of Xa / MgO-MCM-41b, wherein X is at least one of potassium, sodium, or calcium; a represents the mass percentage of X in the total mass of the catalyst, and the value range is 8-12%; MgO-MCM-41 is a mesoporous molecular sieve carrier, and the particle size is 150-600 nm, and the pore size distribution is between 2.8 nm and 3.6 nm; and b represents the molar ratio of Si to Mg in the catalyst, and the value range is 25:1-45:1.

[0008] The above-mentioned M is loaded on the surface and pores of the mesoporous molecular sieve carrier.

[0009] In order to further improve the yield of difurfurylideneacetone, M is potassium or sodium; a is 10-12%. More preferably, the structure of the catalyst used for catalyzing the condensation reaction of furfural and acetone to prepare aviation fuel intermediates is K 10 / MgO-MCM-41(35) or K 12 / MgO-MCM-41(35), more preferably K 10 / MgO-MCM-41(35).

[0010] A method for preparing a catalyst for catalyzing the condensation reaction of furfural and acetone to prepare an aviation fuel intermediate comprises the following steps:

[0011] a) dissolving sodium silicate and magnesium salt in pure water at room temperature and stirring until clear; subsequently, adding a solution of cetyltrimethylammonium bromide (CTAB) dissolved in pure water, stirring and mixing, adjusting the pH to 10-11, and continuing stirring for 2-3 hours; then pouring the solution into a crystallization kettle, statically crystallizing at 120-160° C. for 30-50 hours, cooling to room temperature, filtering, washing with distilled water, and drying to obtain a catalyst precursor, wherein the molar ratio of Si to Mg is 25:1-45:1;

[0012] b) calcining the catalyst precursor at a temperature of 500° C. to 600° C. for 4 to 6 hours to remove the template, and cooling to room temperature to obtain MgO-MCM-41 molecular sieve;

[0013] c) immersing the MgO-MCM-41 molecular sieve in an X salt solution for 18-22 hours, filtering, drying, and calcining at 500° C. to 600° C. for 4-6 hours, and cooling to room temperature to obtain an Xa / MgO-MCM-41b catalyst, wherein X is at least one of K, Na, or Ca, and the mass percentage of X in the total mass of the catalyst is 8-12%.

[0014] In the above steps b) and c), the heating rate of calcination is preferably 3-4°C / min.

[0015] In this application, sodium silicate is used as the silicon source, magnesium salt is used as the magnesium source, and cetyltrimethylammonium bromide (CTAB) is used as the template. After crystallization and calcination, MgO-MCM-41 mesoporous molecular sieve is obtained, which is then impregnated with a specific alkaline solution, dried, and calcined under a nitrogen atmosphere to obtain the X / MgO-MCM-41 catalyst.

[0016] In order to further improve the yield of difurfurylideneacetone, in step a), the magnesium salt is magnesium nitrate or magnesium chloride.

[0017] In the above step c), the X salt solution is an aqueous solution of potassium nitrate, potassium chloride, sodium nitrate, calcium nitrate or calcium chloride, more preferably an aqueous solution of potassium nitrate.

[0018] In order to improve the catalytic effect, it is further preferred that in step c), the mass percentage of X in the total mass of the catalyst is 10-12%.

[0019] The catalyst for catalyzing the condensation reaction of furfural and acetone to prepare an aviation fuel intermediate is used for catalyzing the condensation reaction of furfural and acetone to prepare difurfurylideneacetone, and the yield of difurfurylideneacetone can reach 99.85%.

[0020] Difurfurylideneacetone is an intermediate for aviation fuel.

[0021] As one specific implementation scheme, the above-mentioned catalyst and furfural are uniformly mixed and then pumped into a microchannel reactor with acetone for reaction. The mass of the catalyst accounts for 10% to 20% of the mass of furfural, the molar ratio of furfural to acetone is 2:1 to 3:1, the reaction residence time is 2 to 10 minutes, and the reaction temperature is 30°C to 50°C.

[0022] The present invention provides mild reaction conditions, excellent catalytic activity, high yield and selectivity. In a microchannel reactor, at 35°C and with a reaction residence time of 5 minutes, the acetone conversion rate can reach 100%, and the resulting product, all of which is the dimerization product, difurfurylideneacetone, can be obtained in a yield of over 99.8%.

[0023] As another specific implementation scheme, the present application can also react under conventional conditions. The specific process is: the above-mentioned catalyst is mixed with the raw materials furfural and acetone in a three-necked flask (or a conventional reactor) for reaction, the mass of the catalyst accounts for 10% to 20% of the mass of furfural, the molar ratio of furfural to acetone is 2:1 to 3:1, the reaction time is 30 to 90 minutes, and the reaction temperature is 30°C to 50°C.

[0024] The present invention effectively reduces the reaction temperature and shortens the reaction time. Under conventional conditions, the reaction can be completed in 30 to 90 minutes at 30 to 50°C. The obtained products are all dicondensed products, namely, difurfurylideneacetone, with a yield of over 99.8%. This significantly reduces energy consumption, improves selectivity, and facilitates production.

[0025] After the reaction is completed, the catalyst is filtered out, washed (washed with distilled water 2 to 5 times), and dried (dried at 50 to 80° C. for 6 to 12 hours), and then recovered and reused, which is simple and convenient.

[0026] The technologies not mentioned in this invention are all referred to the prior art.

[0027] The beneficial effects of the present invention are:

[0028] 1. Under mild preparation conditions, by synthesizing the metal oxide skeleton complex MgO-SiO2 and performing hydrothermal treatment, the crystal form and pore structure of the catalyst are effectively controlled, thereby significantly enhancing the mechanical strength and extending the service life of the catalyst.

[0029] 2. The strongly basic mesoporous molecular sieve catalyst prepared by the present invention has excellent catalytic activity, high selectivity for dicondensation products, and high yield. The use of the catalyst of the present invention significantly reduces the reaction temperature and also significantly reduces the reaction time for the condensation of furfural and acetone. Under normal conditions, the reaction only needs to be reacted at 30°C to 50°C for 30 to 90 minutes to complete the reaction, and no other solvents are required, thereby reducing production costs. Using the X / MgO-MCM-41 catalyst (X = K, Na or Ca) prepared by the present invention, the acetone conversion rate can reach 100% under the condition of a 12.5% excess of furfural, and products of the dicondensation product, difurfurylideneacetone, can be obtained, with a yield of more than 99.8%. BRIEF DESCRIPTION OF THE DRAWINGS

[0030] Figure 1a 、 1b The K values are as follows: when the mass percentage of potassium in the total mass of the catalyst is 10% and the molar ratio of silicon to magnesium is 35:1 10 SEM images of the / MgO-MCM-41(35) catalyst at different magnifications. DETAILED DESCRIPTION

[0031] In order to better understand the present invention, the content of the present invention is further illustrated below in conjunction with the examples, but the content of the present invention is not limited to the following examples.

[0032] In each case, if the temperature is not particularly specified, the reaction was carried out at room temperature (15-25° C.); if the stirring speed is not particularly specified, the reaction was carried out at 200 r / min.

[0033] Example 1

[0034] K 10 Preparation of a MgO-MCM-41(35) catalyst, wherein the subscript "10" of potassium indicates that the mass percentage of potassium in the catalyst is 10% of the total mass of the catalyst. The "35" in the bracket indicates that the molar ratio of silicon to magnesium in the catalyst is 35:1.

[0035] K 10 The specific preparation steps of the MgO-MCM-41 (35) catalyst are as follows:

[0036] a) At room temperature, 14.10 g of sodium silicate and 0.49 g of magnesium nitrate were added to a beaker, and then 50 mL of pure water was added and stirred until clear to obtain solution 1; 5.92 g of hexadecyltrimethylammonium bromide (CTAB) was weighed and dissolved in 30 mL of water to obtain solution 2, and solution 1 and solution 2 were mixed and stirred for 2 h, the pH was adjusted to 10.5, and stirring was continued for 3 h; the solution was statically crystallized in a crystallization kettle at 140 ° C for 36 h, naturally cooled to room temperature, filtered, washed with distilled water, and dried in a forced air drying oven at 80 ° C for 12 h to obtain MgO-MCM-41 (35) catalyst precursor.

[0037] b) The MgO-MCM-41(35) catalyst precursor prepared in step a) was heated to 550°C at a heating rate of 3°C / min in a nitrogen atmosphere and calcined for 5.5 h to remove the template, and then naturally cooled to room temperature to obtain a MgO-MCM-41(35) catalyst.

[0038] c) Weigh 5.00 g of the MgO-MCM-41 (35) catalyst prepared in step b) and put it into a potassium nitrate aqueous solution with a concentration of 0.379 mol / L, so that the potassium nitrate solution covers the MgO-MCM-41 (35) catalyst. After thorough mixing and stirring for 4 h, seal and allow to stand at room temperature for 18 h. After filtering and drying, the temperature is raised to 550 ° C. at a heating rate of 3 ° C. / min in a nitrogen atmosphere and calcined for 5.5 h. The mixture is naturally cooled to room temperature to obtain K 10 / MgO-MCM-41(35) catalyst, the SEM images at different magnifications are shown in Figure 1. As shown in Figure 1, the prepared K 10 / MgO-MCM-41(35) catalyst is spherical with a particle size of 150-600 nm and a pore size distribution between 2.8 nm and 3.6 nm.

[0039] Microchannel reaction

[0040] Furfural and acetone with a molar ratio of 2.25:1 were mixed with the above K 10 / MgO-MCM-41(35) catalyst accounts for 15% of furfural by mass, the materials are mixed evenly by a mixer, and then injected into a microchannel reactor by a micro pump, and then the reactor temperature is heated to 35°C, the reaction liquid is retained for 5 minutes, and after the liquid is stabilized, the reaction products are collected for gas phase detection and analysis, and the acetone conversion rate is 100%, and the products are all dicondensation products difurfurylideneacetone, and the yield is 99.85%.

[0041] Conventional reaction

[0042] The 1.76 g K 10 / MgO-MCM-41(35) catalyst, 11.70g furfural and 3.14g acetone were added to a 50mL three-necked flask and stirred magnetically. The mixture was placed in an oil bath with stirring at 200rpm. The reactor was heated to 35°C and the reaction time was 75min. The reaction products were collected and analyzed by gas phase detection. The acetone conversion was 100%, and the products were all dicondensed products, difurfurylideneacetone, with a yield of 99.81%.

[0043] Comparative Example 1

[0044] The difference from Example 1 is that the catalyst is MgO, which is pretreated by heating to 550°C at a heating rate of 3°C / min in a nitrogen atmosphere and calcining for 5.5h, and then naturally cooling to room temperature. The rest is the same as in Example 1.

[0045] Comparative Example 2

[0046] The difference from Example 1 is that the catalyst is NaOH, and the rest are the same as Example 1.

[0047] Comparative Example 3

[0048] The difference from Example 1 is that the catalyst is KOH, and the rest are the same as Example 1.

[0049] Comparative Example 4

[0050] The difference from Example 1 is that the catalyst is CaO, which is pretreated by heating to 550°C at a heating rate of 3°C / min in a nitrogen atmosphere and calcining for 5.5h, and then naturally cooling to room temperature. The rest is the same as in Example 1.

[0051] MgO, KOH, NaOH, and CaO were purchased from Shanghai Aladdin Biochemical Technology Co., Ltd.

[0052] Comparative Example 5

[0053] The difference from Example 1 is that the catalyst is MgO-MCM-41 (35), and the preparation method is the same as steps a) to b) in Example 1, but step c) is not performed. The rest is the same as Example 1.

[0054] Comparative Example 6

[0055] The difference from Example 1 is that the catalyst is K6 / MgO-MCM-41(35), and the preparation method is the same as that of Example 1, wherein the potassium nitrate solution with a concentration of 0.379 mol / L is replaced by a sodium nitrate solution with a concentration of 0.227 mol / L, the subscript 6 of the potassium catalyst indicates that the mass percentage of potassium in the catalyst is 6% of the total mass of the catalyst, and the numbers in the brackets indicate that the molar ratio of silicon to magnesium is 35:1. All other aspects are the same as those of Example 1.

[0056] Comparative Example 7

[0057] The difference from Example 1 is that the catalyst is K8 / MgO-MCM-41 (55), and the preparation method is the same as that of Example 1, wherein 14.10 g of sodium silicate is replaced by 14.28 g of sodium silicate, 0.49 g of magnesium nitrate is replaced by 0.31 g of magnesium nitrate, and the potassium nitrate solution with a concentration of 0.379 mol / L is replaced by a sodium nitrate solution with a concentration of 0.303 mol / L. The subscript 8 of the potassium catalyst indicates that the mass percentage of potassium in the catalyst to the total mass of the catalyst is 8%, and the numbers in the brackets indicate that the molar ratio of silicon to magnesium is 55:1. The rest is the same as that of Example 1.

[0058] Example 2

[0059] The difference from Example 1 is that the catalyst is K 10 / MgO-MCM-41(25), prepared as described in Example 1, except that 14.10 g of sodium silicate was replaced by 13.82 g of sodium silicate, and 0.49 g of magnesium nitrate was replaced by 0.77 g of magnesium nitrate. The subscript 10 of the potassium catalyst indicates that the mass percentage of potassium in the catalyst is 10% of the total mass of the catalyst. The numbers in the brackets indicate that the molar ratio of silicon to magnesium is 25:1. All other aspects are the same as described in Example 1.

[0060] Example 3

[0061] The difference from Example 1 is that the catalyst is K 10 / MgO-MCM-41(45), prepared as described in Example 1, except that 14.10 g of sodium silicate was replaced by 14.15 g of sodium silicate, and 0.49 g of magnesium nitrate was replaced by 0.44 g of magnesium nitrate. The subscript 10 of the potassium catalyst indicates that the mass percentage of potassium in the catalyst is 10% of the total mass of the catalyst. The numbers in the brackets indicate that the molar ratio of silicon to magnesium is 45:1. All other aspects are the same as described in Example 1.

[0062] Example 4

[0063] The difference from Example 1 is that the catalyst is K8 / MgO-MCM-41(35), and the preparation method is the same as that of Example 1, wherein the potassium nitrate solution with a concentration of 0.379 mol / L is replaced by a potassium nitrate solution with a concentration of 0.303 mol / L, the subscript 8 of the catalyst potassium indicates that the mass percentage of potassium in the catalyst is 8% of the total mass of the catalyst, and the numbers in the brackets indicate that the molar ratio of silicon to magnesium is 35:1. The rest is the same as that of Example 1.

[0064] Example 5

[0065] The difference from Example 1 is that the catalyst is K 12 / MgO-MCM-41(35), prepared as described in Example 1, except that the 0.379 mol / L potassium nitrate solution was replaced with a 0.455 mol / L potassium nitrate solution. The subscript 12 of the potassium catalyst indicates that the mass percentage of potassium in the catalyst is 12% of the total mass of the catalyst. The numbers in the brackets indicate that the molar ratio of silicon to magnesium is 35:1. All other aspects are the same as described in Example 1.

[0066] Example 6

[0067] The difference from Example 1 is that the catalyst is Na8 / MgO-MCM-41(35), and the preparation method is the same as that of Example 1, wherein the potassium nitrate solution with a concentration of 0.379 mol / L is replaced by a sodium nitrate solution with a concentration of 0.303 mol / L, the subscript 8 of the catalyst sodium indicates that the mass percentage of sodium in the catalyst to the total mass of the catalyst is 8%, and the numbers in the brackets indicate that the molar ratio of silicon to magnesium is 35:1. All other aspects are the same as those of Example 1.

[0068] Example 7

[0069] The difference from Example 1 is that the catalyst is Na 10 / MgO-MCM-41(35), prepared as described in Example 1, except that the 0.379 mol / L potassium nitrate solution was replaced with a 0.379 mol / L sodium nitrate solution. The subscript 10 of the sodium catalyst indicates that the mass percentage of sodium in the catalyst is 10% of the total mass of the catalyst. The numbers in the brackets indicate that the molar ratio of silicon to magnesium is 35:1. All other aspects are described in Example 1.

[0070] Example 8

[0071] The difference from Example 1 is that the catalyst is Na 12 / MgO-MCM-41(35), prepared as described in Example 1, except that the 0.379 mol / L potassium nitrate solution was replaced with a 0.455 mol / L sodium nitrate solution. The subscript 12 of the catalyst sodium indicates that the mass percentage of sodium in the catalyst is 12% of the total mass of the catalyst. The numbers in the brackets indicate that the molar ratio of silicon to magnesium is 35:1. All other details are as described in Example 1.

[0072] Example 9

[0073] The difference from Example 1 is that the catalyst is Ca8 / MgO-MCM-41(35), and the preparation method is the same as that of Example 1, wherein the potassium nitrate solution with a concentration of 0.379 mol / L is replaced by a calcium nitrate solution with a concentration of 0.303 mol / L. The subscript 8 of the catalyst calcium indicates that the mass percentage of calcium in the catalyst is 8% of the total mass of the catalyst. The numbers in the brackets indicate that the molar ratio of silicon to magnesium is 35:1. All other aspects are the same as those of Example 1.

[0074] Example 10

[0075] The difference from Example 1 is that the catalyst is Ca 10 / MgO-MCM-41(35), prepared as described in Example 1, except that the 0.379 mol / L potassium nitrate solution was replaced with a 0.379 mol / L calcium nitrate solution. The subscript 10 in the catalyst calcium indicates that the mass percentage of calcium in the catalyst is 10% of the total mass of the catalyst. The numbers in the brackets indicate that the molar ratio of silicon to magnesium is 35:1. All other details are as described in Example 1.

[0076] Example 11

[0077] The difference from Example 1 is that the catalyst is Ca 12 / MgO-MCM-41(35), prepared as described in Example 1, except that the 0.379 mol / L potassium nitrate solution was replaced with a 0.455 mol / L calcium nitrate solution. The subscript 12 in the catalyst calcium indicates that the mass percentage of calcium in the catalyst is 12% of the total mass of the catalyst. The numbers in the brackets indicate that the molar ratio of silicon to magnesium is 35:1. All other details are as described in Example 1.

[0078] Example 12

[0079] The difference from Example 1 is that the catalyst is K 10 / MgO-MCM-41(35)-2, the reaction solution in Example 1 was filtered at room temperature, and the recovered catalyst K 10 / MgO-MCM-41(35) was washed with distilled water for 3 times and dried in a forced air drying oven at 80°C for 12 h. The rest of the steps were the same as in Example 1.

[0080] Example 13

[0081] The difference from Example 1 is that the catalyst is K 10 / MgO-MCM-41(35)-3, the reaction solution in Example 12 was filtered at room temperature, and the recovered catalyst K 10 / MgO-MCM-41(35)-2 was washed with distilled water three times and dried in a forced air drying oven at 80°C for 12 hours. The rest of the steps were the same as in Example 1.

[0082] Example 14

[0083] The difference from Example 1 is that the catalyst is K 10 / MgO-MCM-41(35)-4, the reaction solution in Example 13 was filtered at room temperature, and the recovered catalyst K 10 / MgO-MCM-41(35)-3 was washed with distilled water three times and dried in a forced air drying oven at 80°C for 12 hours. The rest of the steps were the same as in Example 1.

[0084] Example 15

[0085] The difference from Example 1 is that the catalyst is K 10 / MgO-MCM-41(35)-5, the reaction solution in Example 14 was filtered at room temperature, and the recovered catalyst K 10 / MgO-MCM-41(35)-4 was washed with distilled water three times and dried in a forced air drying oven at 80°C for 12 hours. The rest of the steps were the same as in Example 1.

[0086] The reaction effects of the catalysts prepared in each example on the condensation of furfural and acetone to prepare difurfurylideneacetone are shown in Table 1, which shows the activity evaluation of different catalysts.

[0087] Table 1 Activity evaluation of different catalysts

[0088]

[0089]

[0090]

[0091] The above acetone conversion rate = (acetone feed amount - acetone remaining amount) / acetone feed amount × 100%; furfurylideneacetone yield = furfurylideneacetone output / theoretical yield of furfurylideneacetone × 100%; difurfurylideneacetone yield = difurfurylideneacetone output / theoretical yield of difurfurylideneacetone × 100%; total product yield = (furfurylideneacetone output + difurfurylideneacetone output) / total theoretical yield × 100%.

[0092] The above description is merely a preferred embodiment of the present invention and is not intended to limit the present invention in any other manner. Any person skilled in the art may utilize the above-disclosed technical content to modify or modify the present invention into equivalent embodiments. However, any simple modifications, equivalent variations, and modifications to the above embodiments that do not depart from the technical content of the present invention and are based on the technical essence of the present invention remain within the scope of protection of the present invention.

Claims

1. A catalyst for catalyzing the condensation reaction of furfural and acetone to prepare an aviation fuel intermediate, characterized in that: The structure is Xa / MgO-MCM-41b, wherein X is at least one of potassium, sodium or calcium; a represents the mass percentage of X in the total mass of the catalyst, and the value range is 8-12%; MgO-MCM-41 is a mesoporous molecular sieve carrier, the particle size is 150-600nm, and the pore size distribution is between 2.8nm and 3.6nm; b represents the molar ratio of Si to Mg in the catalyst, and the value range is 25:1-45:

1.

2. The catalyst for preparing an aviation fuel intermediate by catalyzing the condensation reaction of furfural and acetone according to claim 1, characterized in that: M is potassium or sodium; a is 10 to 12%.

3. The catalyst for preparing an aviation fuel intermediate by catalyzing the condensation reaction of furfural and acetone according to claim 1 or 2, characterized in that: Its structure is K 10 / MgO-MCM-41(35) or K 12 / MgO-MCM-41(35).

4. A method for preparing a catalyst for catalyzing the condensation reaction of furfural and acetone to prepare an aviation fuel intermediate according to any one of claims 1 to 3, characterized in that: The following steps are involved: a) Dissolve sodium silicate and magnesium salt in pure water at room temperature and stir until clear; Subsequently, a solution of hexadecyltrimethylammonium bromide dissolved in pure water was added, stirred and mixed, the pH was adjusted to 10-11, and stirring was continued for 2-3 hours; then the mixture was poured into a crystallization kettle, statically crystallized at 120-160° C. for 30-50 hours, cooled to room temperature, filtered, washed with distilled water, and dried to obtain a catalyst precursor, wherein the molar ratio of Si to Mg is 25:1-45:1; b) calcining the catalyst precursor at a temperature of 500° C. to 600° C. for 4 to 6 hours, and cooling to room temperature to obtain MgO-MCM-41 molecular sieve; c) immersing the MgO-MCM-41 molecular sieve in an X salt solution for 18-22 hours, filtering, drying, and calcining at 500° C. to 600° C. for 4-6 hours, and cooling to room temperature to obtain an Xa / MgO-MCM-41b catalyst, wherein X is at least one of K, Na, or Ca, and the mass percentage of X in the total mass of the catalyst is 8-12%.

5. The preparation method according to claim 4, characterized in that In step a), the magnesium salt is magnesium nitrate or magnesium chloride.

6. The preparation method according to claim 4 or 5, characterized in that In step c), the X salt solution is an aqueous solution of potassium nitrate, potassium chloride, sodium nitrate, calcium nitrate or calcium chloride.

7. The preparation method according to claim 4 or 5, characterized in that In step c), the mass percentage of X in the total mass of the catalyst is 10-12%.

8. Use of the catalyst according to any one of claims 1 to 3 for catalyzing the condensation reaction of furfural and acetone to prepare an aviation fuel intermediate, characterized in that: It is used to catalyze the condensation of furfural and acetone to prepare difurfurylideneacetone, with the yield of difurfurylideneacetone reaching 99.85%.

9. The application according to claim 8, characterized in that: The catalyst according to any one of claims 1 to 3 and furfural are uniformly mixed and then pumped into a microchannel reactor with acetone for reaction, wherein the mass of the catalyst accounts for 10% to 20% of the mass of the furfural, the molar ratio of furfural to acetone is 2:1 to 3:1, the reaction residence time is 2 to 10 minutes, and the reaction temperature is 30° C. to 50° C.

10. The application according to claim 8, characterized in that: The catalyst according to any one of claims 1 to 3 is mixed with raw materials furfural and acetone in a three-necked flask for reaction, wherein the mass of the catalyst accounts for 10% to 20% of the mass of the furfural, the molar ratio of furfural to acetone is 2:1 to 3:1, the reaction time is 30 to 90 minutes, and the reaction temperature is 30° C. to 50° C.

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