Fuel precursors, fuels and their preparation methods
By heating a mixture of furanol, organic extractant, and acidic molecular sieve catalyst, combined with a hydrodeoxygenation step, the problem of low biomass fuel yield was solved, and a method for efficiently preparing C9-C15 fuel precursors and fuels was realized, improving yield and separation and purification efficiency.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Patents(China)
- Current Assignee / Owner
- TIANJIN UNIV
- Filing Date
- 2024-12-31
- Publication Date
- 2026-05-26
AI Technical Summary
In existing technologies, the yield of hydrocarbon fuels in the C9-C15 range obtained from biomass energy sources such as lignocellulose is low, with a maximum yield of only 10%-15%, which is insufficient to meet the demand for aviation fuel.
A mixture of furanol, organic extractant, water, and acidic molecular sieve catalyst was heated under an inert atmosphere to prepare a fuel precursor using a two-phase extraction method, which was then followed by hydrogenation deoxygenation to obtain the fuel.
It improves the conversion rate and yield of furan alcohol to C9-C15 fuel precursors, achieves efficient separation and purification of fuel precursors, and reduces production costs.
Smart Images
Figure CN119979232B_ABST
Abstract
Description
Technical Field
[0001] This application relates to the field of chemical technology, specifically to fuel precursors, fuels, and methods for their preparation. Background Technology
[0002] Traditional aviation kerosene is primarily sourced from fossil fuels such as petroleum and coal. To optimize the energy structure, replacing traditional fossil fuels with biomass energy sources such as lignocellulose is a viable alternative. Currently, hydrocarbon fuels in the C9-C15 range are considered excellent aviation fuel components. However, due to limitations in related technologies, the yield of C9-C15 hydrocarbon fuels obtained from biomass energy sources such as lignocellulose is low, with the highest yield being only around 10%-15%. Summary of the Invention
[0003] In view of this, embodiments of this application provide a fuel precursor, a fuel, and a method for preparing the same.
[0004] The first aspect of this application provides a method for preparing a fuel precursor, comprising:
[0005] Furan alcohol, organic extractant, water and acidic molecular sieve catalyst are mixed to obtain a mixture;
[0006] The mixture is heated under an inert atmosphere to obtain the fuel precursor.
[0007] In one embodiment, the furanol comprises at least one selected from furfuryl alcohol, furfuryl alcohol derivatives, 5-methylfurfuryl alcohol, 5-methylfurfuryl alcohol derivatives, 5-hydroxymethylfurfural, and 5-hydroxymethylfurfural derivatives.
[0008] In one embodiment, the organic extractant includes at least one of toluene and p-xylene.
[0009] In one embodiment, the silicon-to-aluminum ratio of the acidic molecular sieve catalyst is 20 to 100;
[0010] Preferably, the acidic molecular sieve catalyst includes at least one of Hβ, HY, Al-MCM-41, Al-SBA-15 and Al-SBA-16.
[0011] In one embodiment, the mass of the acidic molecular sieve catalyst is 5 wt% to 16 wt% of the mass of the raw material furanol;
[0012] Preferably, the mass ratio of furanol, water and organic extractant is 1:1:(0.2-2).
[0013] In one embodiment, the mixture is heated to a temperature of 80°C to 110°C for a time of 6 to 12 hours.
[0014] Preferably, the mixture is heated under stirring conditions;
[0015] Preferably, the stirring speed is 500 to 1000 rpm.
[0016] In one embodiment, after heating the mixture, the fuel precursor is dispersed in the organic extractant, and water and the organic extractant are separated to obtain the fuel precursor containing the organic extractant.
[0017] The fuel precursor containing the organic extractant is separated and purified to obtain the fuel precursor.
[0018] A second aspect of this application provides a fuel precursor prepared by the aforementioned preparation method, comprising at least one of the structural formulas shown in formulas (1) to (3):
[0019]
[0020] Where m equals 0 or 1, and n equals 1 or 2.
[0021] A third aspect of this application provides a method for preparing a fuel, wherein the aforementioned fuel precursor or the fuel precursor prepared by the aforementioned method is subjected to hydrogenation and deoxygenation to obtain the fuel.
[0022] In one embodiment, the method for preparing the fuel includes:
[0023] The fuel precursor, solvent and first hydrodeoxygenation catalyst are mixed and then subjected to a first reaction.
[0024] The product obtained after the first reaction is mixed with the first hydrodeoxygenation catalyst and the second hydrodeoxygenation catalyst to carry out a second reaction, thereby obtaining the fuel;
[0025] Preferably, the first hydrodeoxygenation catalyst comprises Pd / C, and the second hydrodeoxygenation catalyst comprises HZSM-5 molecular sieve;
[0026] Preferably, the conditions for the first reaction include at least one of the following: a temperature of 140–160°C; a pressure of 3–5 MPa; a hydrogen atmosphere; and a time of 5–8 hours.
[0027] Preferably, the conditions for the second reaction include at least one of the following: a temperature of 240–260°C; a pressure of 3–5 MPa; a hydrogen atmosphere; and a time of 10–14 h.
[0028] According to the method for preparing fuel precursors provided in this application, the mixture contains water, an organic extractant, and furanol. Initially, furanol is distributed in both the aqueous and organic phases. Upon heating the mixture, the reaction mainly occurs in the aqueous phase. The selected acidic molecular sieve catalyst has good hydrophilicity. As the reaction proceeds, furanol continuously diffuses into the aqueous phase and reacts. Simultaneously, the organic extractant can promptly extract the target product, the fuel precursor, into the organic phase, avoiding further polymerization and improving the yield of the fuel precursor. Furthermore, the two-phase system facilitates the separation and purification of the fuel precursor. This application can achieve efficient conversion from furanol to C9-C15 aviation fuel precursors. Attached Figure Description
[0029] Figure 1 This is a schematic diagram of a method for preparing a fuel precursor in one embodiment of this application.
[0030] Figure 2 The graph shows the results of furan alcohol conversion and fuel precursor selectivity in Examples 1-3 and Comparative Examples 1-3. Detailed Implementation
[0031] The technical solutions of the embodiments of this application will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of this application, and not all embodiments. Based on the embodiments of this application, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of this application.
[0032] Furthermore, to better illustrate this application, numerous specific details are provided in the following detailed embodiments. Those skilled in the art should understand that this application can be implemented even without certain specific details. In some instances, methods and means well-known to those skilled in the art have not been described in detail in order to highlight the main points of this application.
[0033] It should be noted that similar labels and letters in the following figures indicate similar items. Therefore, once an item is defined in one figure, it does not need to be further defined and explained in subsequent figures.
[0034] Furthermore, the terms "first" and "second" are used only to distinguish descriptions and should not be interpreted as indicating or implying relative importance.
[0035] The first aspect of this application provides a method for preparing the aforementioned fuel precursor, referring to... Figure 1 The diagram shows a process flow chart for preparing fuel precursors, which includes the following steps.
[0036] S100: Furan alcohol, organic extractant, water and acidic molecular sieve catalyst are mixed to obtain a mixture.
[0037] Understandably, this application uses solid acidic molecular sieves as catalysts and employs a two-phase system containing organic extractant and water for reaction extraction. Due to the use of a two-phase system, the product is distributed in the organic phase, which facilitates separation and solves the problem of low yield in the synthesis of the target product fuel precursor using furan alcohol oligomerization reaction. Furthermore, acidic molecular sieves as catalysts can be recycled and reused, which helps to reduce production costs.
[0038] In one embodiment, the silicon-to-aluminum ratio of the acidic molecular sieve catalyst is 20–100, for example, it can be 20, 30, 40, 50, 60, 70, 80, 90, or 100. It should be noted that the silicon-to-aluminum ratio of the acidic molecular sieve catalyst refers to the molar ratio of SiO2 to Al2O3 in the acidic molecular sieve catalyst. Therefore, the above-mentioned acidic molecular sieve catalyst is beneficial for improving the selectivity of fuel precursors.
[0039] In one embodiment, the acidic molecular sieve catalyst comprises at least one of Hβ, HY, Al-MCM-41, Al-SBA-15, and Al-SBA-16. Using a molecular sieve with good hydrophilicity is beneficial for improving the conversion rate of furanol; using a molecular sieve with relatively low acidity is beneficial for improving the selectivity of fuel precursors.
[0040] In one embodiment, the furanol comprises at least one of furfuryl alcohol derivatives, 5-methylfurfuryl alcohol, 5-methylfurfuryl alcohol derivatives, 5-hydroxymethylfurfural, and 5-hydroxymethylfurfural derivatives.
[0041] In one embodiment, the organic extractant includes at least one of toluene and p-xylene.
[0042] In one embodiment, the mass of the acidic molecular sieve catalyst is 5 wt% to 16 wt% of the mass of the raw material furanol, for example, it can be 5 wt%, 6 wt%, 8 wt%, 10 wt%, 12 wt%, 14 wt%, or 16 wt%. Relative to the above dosage range, when the amount of acidic molecular sieve catalyst is less than 5 wt%, the furanol conversion rate is low; when the amount of acidic molecular sieve catalyst is greater than 16 wt%, the fuel precursor undergoes further condensation to form macromolecules, resulting in reduced selectivity.
[0043] In one embodiment, the mass ratio of furanol, water, and the organic extractant is 1:1.
[0044] (0.2~2), for example, it can be 1:1:0.2, 1:1:0.5, 1:1:1, 1:1:1.5 or 1:1:2, etc. Compared with the above ratio range, when the amount of organic extractant is small, the fuel precursor cannot be extracted into the extract phase in time, while when the amount of organic extractant is large, the improvement on furanol conversion rate and fuel precursor selectivity is not significant.
[0045] S200: The mixture is heated under an inert atmosphere to obtain the fuel precursor.
[0046] In one embodiment, the temperature of the mixture is 80°C to 110°C (e.g., 80°C, 90°C, 100°C, or 110°C) and the time is 6 to 12 hours (e.g., 6 hours, 8 hours, 10 hours, or 12 hours).
[0047] In one embodiment, the mixture is heated under stirring conditions. This allows the organic extractant to promptly extract the target product, the fuel precursor, into the organic phase, preventing further polymerization and increasing the yield of the fuel precursor.
[0048] In one embodiment, the stirring speed is 500 to 1000 rpm, for example, 500 rpm, 600 rpm, 700 rpm, 800 rpm, 900 rpm, or 1000 rpm.
[0049] In one embodiment, after heating the mixture, the fuel precursor is dispersed in the organic extractant, water and the organic extractant are separated to obtain the fuel precursor containing the organic extractant; the fuel precursor containing the organic extractant is then separated and purified to obtain the fuel precursor.
[0050] According to the method for preparing fuel precursors provided in this application, the mixture contains water, an organic extractant, and furanol. Initially, furanol is distributed in both the aqueous and organic phases. Upon heating the mixture, the reaction mainly occurs in the aqueous phase. The selected acidic molecular sieve catalyst has good hydrophilicity. As the reaction proceeds, furanol continuously diffuses into the aqueous phase and reacts. Simultaneously, the organic extractant can promptly extract the target product, the fuel precursor, into the organic phase, avoiding further polymerization and improving the yield of the fuel precursor. Furthermore, the two-phase system facilitates the separation and purification of the fuel precursor. This application can achieve efficient conversion from furanol to C9-C15 aviation fuel precursors.
[0051] A second aspect of this application provides a fuel precursor prepared by the aforementioned preparation method, comprising at least one of the structural formulas shown in formulas (1) to (3):
[0052]
[0053] Where m equals 0 or 1, and n equals 1 or 2.
[0054] A third aspect of this application provides a fuel comprising the structural formula (4):
[0055]
[0056] Where x is an integer greater than or equal to 7 and less than or equal to 13, such as 7, 8, 9, 10, 11, 12 or 13, etc.
[0057] The fourth aspect of this application provides a method for preparing a fuel, wherein the aforementioned fuel precursor or the fuel precursor prepared by the aforementioned method is subjected to hydrogenation and deoxygenation to obtain the fuel.
[0058] In one embodiment, the fuel preparation method includes: mixing the fuel precursor, solvent, and a first hydrodeoxygenation catalyst and then carrying out a first reaction; mixing the product obtained after the first reaction with the first hydrodeoxygenation catalyst and a second hydrodeoxygenation catalyst and then carrying out a second reaction to obtain the fuel.
[0059] In one embodiment, the first hydrodeoxygenation catalyst comprises Pd / C, and the second hydrodeoxygenation catalyst comprises HZSM-5 molecular sieve.
[0060] In one embodiment, the conditions for the first reaction include at least one of the following: a temperature of 140–160°C; a pressure of 3–5 MPa; a hydrogen atmosphere; and a time of 5–8 h.
[0061] In one embodiment, the conditions for the second reaction include at least one of the following: a temperature of 240–260°C; a pressure of 3–5 MPa; a hydrogen atmosphere; and a time of 10–14 h.
[0062] For example, the hydrodeoxygenation step of the fuel precursor includes: mixing the fuel precursor, solvent (e.g., cyclohexane), and Pd / C catalyst, and reacting at 140–160°C, 3–5 MPa, and a hydrogen atmosphere for 5–8 hours. After the reaction, the old catalyst is separated by centrifugation, and fresh Pd / C catalyst and HZSM-5 molecular sieve catalyst are added back in, and the reaction is carried out at 240–260°C, 3–5 MPa, and a hydrogen atmosphere for 10–14 hours.
[0063] The present application will be further described below with reference to specific embodiments. It should be noted that the following embodiments are only used to explain the present application and should not be construed as limiting the present application.
[0064] Example 1
[0065] The preparation method of fuel precursor includes the following steps:
[0066] (1) First, calcine the Al-MCM-41 molecular sieve at 580℃ for 3h to remove the impurities it adsorbs.
[0067] (2) At 100℃ and under N2 atmosphere, add 5g furfuryl alcohol, 5g toluene and 5g water to a 25mL reactor.
[0068] (3) Weigh 0.6g of calcined Al-MCM-41 molecular sieve and add it to the solution in step (2) under magnetic stirring at 600rpm. React for 8h.
[0069] (4) After the reaction is complete, separate the organic phase from the aqueous phase; collect the organic phase and analyze the product components using a gas chromatography-mass spectrometry (GC-MS) and a gas chromatograph.
[0070] In this embodiment, the furfuryl alcohol conversion rate was 81%, and the fuel precursor yield was 34.1%.
[0071] Example 2-21
[0072] The preparation methods of fuel precursors in Examples 2-21 are basically the same as those in Example 1, except for the following: type of furanol, heating temperature, heating time, amount of acidic molecular sieve catalyst, type of acidic molecular sieve catalyst, type of organic extractant, mass ratio of furanol, water to organic extractant, etc., as shown in Table 1. The conversion rate of furanol and the yield of fuel precursors are also shown in Table 1 below.
[0073] Table 1
[0074]
[0075]
[0076] The results above show that using acidic molecular sieves as catalysts for the oligomerization of furanol, combined with reaction extraction, results in high catalyst activity, high furanol conversion, and high yield of target products. The yield of C9-C15 compounds can reach up to 71.56%.
[0077] Comparative Example 1
[0078] The preparation method of the fuel precursor in this comparative example is basically the same as that in Example 1, except that the catalyst Al-MCM-41 is replaced with HY-5.3. In this comparative example, the conversion rate of furfuryl alcohol is 83.4%, and the yield of C9-C15 compound is 13.6%.
[0079] Comparative Example 2
[0080] The preparation method of the aviation fuel precursor in this comparative example is basically the same as that in Example 1, except that the heating temperature is increased to 150°C. In this comparative example, the conversion rate of furfuryl alcohol is 100%, and the yield of C9-C15 compound is 16.8%.
[0081] Comparative Example 3
[0082] The preparation method of aviation fuel precursor in this comparative example is basically the same as in Example 1, except that the organic extractant is replaced with dioxane. In this comparative example, the conversion rate of furfuryl alcohol is 91.30%, and the yield of C9-C15 compound is 3.68%.
[0083] The results of furan alcohol conversion and fuel precursor selectivity in Examples 1-3 and Comparative Examples 1-3 are as follows: Figure 2 In the preparation method of this application embodiment, the furan alcohol conversion rate and fuel precursor selectivity are both high.
[0084] The basic principles of this application have been described above with reference to specific embodiments. However, it should be noted that the advantages, benefits, and effects mentioned in this application are merely examples and not limitations, and should not be considered as essential features of each embodiment of this application. Furthermore, the specific details disclosed above are for illustrative and facilitative purposes only, and are not limitations. These details do not limit the application to the necessity of employing the aforementioned specific details for implementation.
[0085] The above description has been given for purposes of illustration and description. Furthermore, this description is not intended to limit the embodiments of this application to the forms disclosed herein. Although numerous exemplary aspects and embodiments have been discussed above, those skilled in the art will recognize certain variations, modifications, alterations, additions, and sub-combinations thereof.
Claims
1. A method for preparing a fuel precursor, characterized in that, include: A mixture is prepared by mixing furanol, an organic extractant, water, and an acidic molecular sieve catalyst; the organic extractant includes p-xylene; the silica-to-alumina ratio of the acidic molecular sieve catalyst is 20-100; the acidic molecular sieve catalyst includes at least one of Hβ, HY, Al-MCM-41, Al-SBA-15, and Al-SBA-16; and the furanol includes at least one of furfuryl alcohol, 5-methylfurfural, and 5-hydroxymethylfurfural. The mixture is heated under an inert atmosphere to obtain the fuel precursor; the temperature of the mixture is 80℃~110℃ and the time is 6~12 h.
2. The preparation method according to claim 1, characterized in that, The mass of the acidic molecular sieve catalyst is 5 wt% to 16 wt% of the mass of the raw material furanol; And / or, the mass ratio of furanol, water and organic extractant is 1:1:(0.2-2).
3. The preparation method according to claim 1, characterized in that, The mixture is heated under stirring conditions.
4. The preparation method according to claim 3, characterized in that, The stirring speed is 500~1000 rpm.
5. The preparation method according to claim 1, characterized in that, After heating the mixture, the fuel precursor is dispersed in the organic extractant, and water and the organic extractant are separated to obtain the fuel precursor containing the organic extractant. The fuel precursor containing the organic extractant is separated and purified to obtain the fuel precursor.
6. A method for preparing a fuel, characterized in that, The fuel precursor prepared by any one of claims 1 to 5 is subjected to hydrogenation and deoxygenation to obtain the fuel.
7. The preparation method according to claim 6, characterized in that, include: The fuel precursor, solvent and first hydrodeoxygenation catalyst are mixed and then subjected to a first reaction. The product obtained after the first reaction is mixed with the first and second hydrodeoxygenation catalysts and then subjected to a second reaction to obtain the fuel.
8. The preparation method according to claim 7, characterized in that, The first hydrodeoxygenation catalyst comprises Pd / C, and the second hydrodeoxygenation catalyst comprises HZSM-5 molecular sieve; And / or, the conditions for the first reaction include at least one of the following: a temperature of 140-160°C; a pressure of 3-5 MPa; a hydrogen atmosphere; and a time of 5-8 h; And / or, the conditions for the second reaction include at least one of the following: a temperature of 240-260°C; a pressure of 3-5 MPa; a hydrogen atmosphere; and a time of 10-14 h.