Biomass-based fuel, precursor of biomass-based fuel, preparation method of biomass-based fuel and aerospace fuel

Abstract

The invention provides a biomass-based fuel, a precursor of the biomass-based fuel, a preparation method of the precursor and an aerospace fuel. The biomass-based fuel precursor comprises at least one of the structural formulas shown in the formula (1) to the formula (11). The biomass-based fuel precursor has an accurately constructed high-tension four-membered ring high-tension structure, molecules have high tension energy, and the biomass-based fuel precursor can be used for preparing biomass-based fuel with high density (0.905-0.92 g / cm < 3 >), high quality net heat value (the quality net heat value is not lower than 42.59 MJ / kg) and low freezing point (the freezing point is lower than-60 DEG C) at the same time. And for an aerospace craft with a fixed fuel tank volume, the voyage, the navigational speed and the load of the aerospace craft can be effectively improved.

Description

Technical Field

[0001] The present application relates to the field of fuel technology, in particular to biomass-based fuels, their precursors and preparation methods, and aerospace fuels. Background Art

[0002] Aerospace fuels face challenges such as a lack of precise fuel structure design and the difficulty of conducting some reactions under thermal catalysis. These issues result in low energy density and a high freezing point, making them difficult to meet the high-quality, sustainable aerospace fuel requirements of next-generation aircraft. In light of these challenges, the present invention was developed. Summary of the Invention

[0003] In view of this, embodiments of the present application provide a biomass-based fuel, a precursor thereof, a preparation method thereof, and an aerospace fuel.

[0004] In a first aspect, the present application provides a biomass-based fuel precursor comprising at least one of the structural formulas shown in formula (1) to formula (11):

[0005]

[0006]

[0007] In one embodiment, the biomass-based fuel precursor includes structural formulas as shown in Formulas (4) to (7), and the mole fractions of the structural formulas shown in Formulas (4) to (7) are 30% to 40% for Formula (4), 40% to 50% for Formula (5), 10% to 20% for Formula (6), and 3% to 6% for Formula (7).

[0008] A second aspect of the present application provides a method for preparing a biomass-based fuel precursor, comprising:

[0009] mixing isophorone, terpinene and a solvent to obtain a mixed solution;

[0010] The mixed solution is irradiated with ultraviolet light to cause an intermolecular [2+2] cycloaddition reaction between isophorone and terpinene to obtain the biomass-based fuel precursor.

[0011] In one embodiment, the terpinene comprises at least one of β-terpinene, γ-terpinene and δ-terpinene;

[0012] Preferably, the molar ratio of isophorone to terpinene is 1:(1-4);

[0013] Preferably, before the intermolecular [2+2] cycloaddition reaction occurs, an inert gas is introduced into the mixed solution for 0.5 to 2 hours.

[0014] In one embodiment, the intermolecular [2+2] cycloaddition reaction is carried out at a temperature of 0 to 40° C. and for a time of 1 to 24 h;

[0015] Preferably, the ultraviolet light wavelength range is 320-390 nm;

[0016] Preferably, the intensity of the ultraviolet light is 130-220 mW / cm 2 ;

[0017] Preferably, the solvent comprises at least one of methanol, ethanol, isopropanol, acetonitrile and dichloromethane;

[0018] Preferably, in the mixed solution, the mass content of the solvent is 10 to 50 wt%.

[0019] A third aspect of the present application provides a biomass-based fuel comprising at least one of the structural formulas shown in formulas (12) to (18):

[0020]

[0021]

[0022] A fourth aspect of the present application provides a method for preparing a biomass-based fuel, comprising:

[0023] subjecting the aforementioned biomass-based fuel precursor to a hydrodeoxygenation reaction to obtain the biomass-based fuel; and / or,

[0024] The biomass-based fuel precursor prepared by the above-mentioned preparation method is subjected to a hydrodeoxygenation reaction to obtain the biomass-based fuel.

[0025] In one embodiment, subjecting the biomass-based fuel precursor to a hydrodeoxygenation reaction comprises:

[0026] In a hydrogen atmosphere, the biomass-based fuel precursor undergoes a hydrodeoxygenation reaction by the combined action of a hydrogenation catalyst and a molecular sieve, the hydrogen pressure is 0.5-3 MPa, the hydrodeoxygenation reaction time is 1-12 hours, and the temperature is 160-200°C;

[0027] Preferably, the hydrogenation catalyst includes at least one of Pd / C, Rh / C, Pt / C, Pd / Fe2O3, and Pd / TiO2, and the molecular sieve includes at least one of ZSM-5, HY, H-β, Pt / HY, and Pt / H-β.

[0028] In one embodiment, subjecting the biomass-based fuel precursor to a hydrodeoxygenation reaction comprises:

[0029] The biomass-based fuel precursor, hydrazine hydrate and a high-boiling-point alcohol solution are mixed and heated under reflux to generate hydrazone, and then water and excess hydrazine are distilled off to obtain an intermediate product;

[0030] The intermediate product is mixed with a base and heated, and when the temperature reaches 195-205° C., refluxed for 5-6 hours and then subjected to hydrogenation reaction to obtain the biomass-based fuel;

[0031] Preferably, the biomass-based fuel precursor, hydrazine hydrate and high-boiling-point alcohol solution are mixed and heated to 150° C. and refluxed for 4 to 8 hours to generate hydrazone;

[0032] Preferably, the high-boiling-point alcohol solution includes diethylene glycol and / or triethylene glycol, the base includes at least one of potassium hydroxide, sodium hydroxide, potassium tert-butoxide and sodium ethoxide, and the hydrazine hydrate includes 50 wt% hydrazine hydrate and / or 80% wt hydrazine hydrate.

[0033] Preferably, the conditions for the hydrogenation reaction include at least one of the following:

[0034] The hydrogen pressure is 0.5-3MPa;

[0035] The hydrogenation reaction time is 1-12h;

[0036] Temperature is 80-120℃;

[0037] The hydrogenation catalyst includes at least one of Pd / C, Rh / C, Pt / C, Pd / Fe2O3 and Pd / TiO2.

[0038] In a fifth aspect, the present application provides an aerospace fuel, including the biomass-based fuel described above, and / or, including the biomass-based fuel prepared by the preparation method described above.

[0039] The biomass-based fuel precursor provided by the embodiment of the present application has a precisely constructed high-tension four-membered ring high-tension structure, and the molecule has high tension energy. The biomass-based fuel precursor of the present application can be used to prepare a biomass-based fuel having a high density (0.905-0.92 g / cm 3 ), high-quality net calorific value (mass net calorific value is not less than 42.59MJ / kg), and low freezing point (freezing point is less than -60℃) biomass-based fuels can effectively increase the range, speed, and payload of aerospace vehicles with a fixed fuel tank volume. BRIEF DESCRIPTION OF THE DRAWINGS

[0040] Figure 1 This is a schematic flow chart of a method for preparing a biomass-based fuel precursor in one embodiment of the present application.

[0041] Figure 2 This is a gas chromatography-mass spectrometry diagram of the biomass-based fuel of Example 17 of the present application.

[0042] Figure 3 This is the gas chromatography-mass spectrometry ion peak distribution diagram of the biomass-based fuel in Example 17 of the present application.

[0043] Figure 4 This is the infrared spectrum of the biomass-based fuel of Example 17 of the present application.

[0044] Figure 5 This is the hydrogen nuclear magnetic resonance spectrum of the biomass-based fuel of Example 17 of the present application. DETAILED DESCRIPTION

[0045] The following will be combined with the drawings in the embodiments of this application to clearly and completely describe the technical solutions in the embodiments of this application. Obviously, the embodiments described are only part of the embodiments of this application, not all of the embodiments. Based on the embodiments in this application, all other embodiments obtained by ordinary technicians in this field without making creative efforts are within the scope of protection of this application.

[0046] In addition, in order to better illustrate the present application, numerous specific details are provided in the following detailed description. Those skilled in the art will understand that the present application can be practiced without certain specific details. In some examples, methods and means well known to those skilled in the art are not described in detail in order to highlight the main purpose of the present application.

[0047] It should be noted that similar reference numerals and letters denote similar items in the following drawings, and therefore, once an item is defined in one drawing, it does not need to be further defined or explained in subsequent drawings.

[0048] In addition, the terms "first", "second", etc., if used, are merely used to distinguish and describe, and should not be understood as indicating or implying relative importance.

[0049] In a first aspect, the present application provides a biomass-based fuel precursor comprising at least one of the structural formulas shown in formula (1) to formula (11):

[0050]

[0051] The biomass-based fuel precursor provided by the embodiment of the present application has a precisely constructed high-tension four-membered ring high-tension structure, and the molecule has high tension energy. The biomass-based fuel precursor of the present application can be used to prepare a biomass-based fuel having a high density (0.905-0.92 g / cm 3 ), high-quality net calorific value (mass net calorific value is not less than 42.59MJ / kg), and low freezing point (freezing point is less than -60℃) biomass-based fuels can effectively increase the range, speed, and payload of aerospace vehicles with a fixed fuel tank volume.

[0052] It is understood that the molecular formula of the biomass-based fuel precursor may include only any one of the structural formulas shown in formulas (1) to (11) above, or may include a mixture of at least two of the structural formulas shown in formulas (1) to (11) above.

[0053] For example, the biomass-based fuels obtained after hydrodeoxygenation of the three structures of formula (2), formula (10), and formula (11) have high calorific values; the biomass-based fuel obtained after hydrodeoxygenation of formula (1) has low freezing point and viscosity, which is conducive to improving the fluidity of the biomass-based fuel. Increasing the content of the multi-ring structures of formula (2), formula (3), formula (4), formula (5), formula (6), and formula (7) can produce biomass-based fuels with higher density after hydrodeoxygenation.

[0054] In one embodiment, the biomass-based fuel precursor includes the structural formulas shown in formulas (4) to (7), and the mole fractions of the structural formulas shown in formulas (4) to (7) are 30% to 40% of formula (4) (for example, 30%, 32%, 34%, 36%, 37%, 38% or 40%, etc.), respectively. Formula (5)

[0055] 40% to 50% (for example, 40%, 42%, 44%, 46%, 47%, 48% or 50%, etc.), formula (6) 10% to 20% (for example, 10%, 12%, 14%, 15%, 16%, 18% or 20%, etc.), and formula (7) 3% to 6% (for example, 3%, 4%, 5% or 6%, etc.).

[0056] The second aspect of the present application provides a method for preparing a biomass-based fuel precursor, referring to Figure 1 The schematic diagram of the preparation method of the biomass-based fuel precursor is shown, and the preparation method of the biomass-based fuel precursor includes the following steps.

[0057] S100: mixing isophorone, terpinene and a solvent to obtain a mixed solution.

[0058] In one embodiment, the preparation method of isophorone includes a liquid phase condensation method, a gas phase condensation method, or a gas-liquid combined method.

[0059] Optionally, the terpinene includes at least one of β-terpinene, γ-terpinene and δ-terpinene.

[0060] In some embodiments of the invention, the molecular formula of isophorone is The molecular formula of β-terpinene is The molecular formula of γ-terpinene is The molecular formula of δ-terpinene is

[0061] S200: irradiating the mixed solution with ultraviolet light to cause an intermolecular [2+2] cycloaddition reaction between isophorone and terpinene to obtain the biomass-based fuel precursor.

[0062] For example, the specific reaction formula of the above-mentioned intermolecular [2+2] cycloaddition reaction can be as follows:

[0063]

[0064] A biomass-based fuel precursor with high tension performance can be obtained through a one-step cycloaddition reaction. The biomass-based fuel precursor simultaneously contains the molecular formulas represented by formula (1), formula (2), formula (3), formula (4), formula (5), formula (6), formula (7), formula (8), formula (9), formula (10), and formula (11). In a mixed solution, isophorone is excited by ultraviolet light to a singlet state, which then undergoes interstitial crossing to a triplet state and then reacts with terpinene to obtain a biomass-based fuel precursor.

[0065] Optionally, the above-mentioned ultraviolet light irradiation conditions can be provided by a 365nm LED integrated lamp group, or by a 340nm LED integrated lamp group; illustratively, a 365nm LED integrated lamp group is used to irradiate isophorone and terpinene, causing them to undergo copolymerization reaction in a solvent.

[0066] Optionally, the ultraviolet light has a wavelength range of 320 to 390 nm, for example, 325 nm, 340 nm, 360 nm, 365 nm, 380 nm or 390 nm. When the wavelength is lower than 320 nm, the raw material will self-photodegrade without copolymerization reaction. When the wavelength is higher than 390 nm, isophorone cannot be excited to cause the reaction.

[0067] Optionally, the intensity of the ultraviolet light is 130-220 mW / cm 2 ; Light intensity is less than 130mW / cm 2 When the light intensity is higher than 220mW / cm 2 When the temperature of the reaction system rises sharply due to long-term irradiation, the temperature cannot be controlled.

[0068] In one embodiment, the molar ratio of isophorone to terpinene is 1:(1-4), for example, 1:1, 1:2, 1:3, or 1:4. Thus, the ratio of isophorone to terpinene is appropriate, and a biomass-based fuel precursor can be efficiently obtained.

[0069] Preferably, before the intermolecular [2+2] cycloaddition reaction occurs, an inert gas (e.g., nitrogen) is introduced into the mixed solution for 0.5 to 2 hours (e.g., 0.5 hours, 1 hour, 1.5 hours, or 2 hours). This effectively removes oxygen from the reaction system and reduces the occurrence of side reactions.

[0070] In one embodiment, the temperature of the intermolecular [2+2] cycloaddition reaction is 0-40°C (for example, 0°C, 10°C, 20°C, 30°C or 40°C, etc.), and the time is 1-24h (for example, 1h, 2h, 4h, 6h, 8h, 10h, 12h, 14h, 16h, 18h, 20h, 22h or 24h, etc.). Thus, the reaction process is simple and the reaction conditions are mild. When the temperature of the intermolecular [2+2] cycloaddition reaction is higher than 40°C, the product yield remains substantially unchanged, and an external reflux device and additional temperature control facilities are required, which increases the synthesis cost.

[0071] In one embodiment, the solvent comprises at least one of methanol, ethanol, isopropanol, acetonitrile and dichloromethane. Thus, the material is widely available, relatively cheap, and is not likely to react with the reactants, thus not introducing new by-products.

[0072] In one embodiment, in the mixed solution, the mass content of the solvent is 10-50 wt%, for example, 10 wt%, 15 wt%, 20 wt%, 25 wt%, 30 wt%, 35 wt%, 40 wt%, 45 wt%, or 50 wt%. With respect to the above contents, when the solvent content is less than 10 wt%, the product yield is low; when the solvent content is greater than 50 wt%, the product yield is too low, the solvent usage is too large, and the solvent loss during separation and purification is large.

[0073] A third aspect of the present application provides a biomass-based fuel comprising at least one of the structural formulas shown in formulas (12) to (18):

[0074]

[0075] For example, biomass-based fuels having formulas (14), (17), and (18) have higher calorific values ​​than other components, and biomass-based fuels having formula (12) have lower freezing points and lower viscosities, resulting in higher fluidity. Increasing the content of the multi-ring structures of formulas (13), (15), and (16) can increase the density of the biomass-based fuel.

[0076] The biomass-based fuel of the embodiment of the present application has a high-tension structure and high-tension performance, and also has a high density (0.905-0.92 g / cm 3), high-quality net calorific value (mass net calorific value is not less than 42.59MJ / kg) and low freezing point (freezing point <-60℃), which can effectively improve the range, speed and payload of aerospace vehicles with a fixed fuel tank volume.

[0077] A fourth aspect of the present application provides a method for preparing a biomass-based fuel, comprising:

[0078] subjecting the aforementioned biomass-based fuel precursor to a hydrodeoxygenation reaction to obtain the biomass-based fuel; and / or,

[0079] The biomass-based fuel precursor prepared by the above-mentioned preparation method is subjected to a hydrodeoxygenation reaction to obtain the biomass-based fuel.

[0080] It can be understood that the above-mentioned hydrodeoxygenation reaction is to reduce the carbonyl group in the molecular formula of the biomass-based fuel precursor to a methylene group, and simultaneously saturate the double bond to a single bond.

[0081] In one embodiment, subjecting the biomass-based fuel precursor to a hydrodeoxygenation reaction comprises:

[0082] Under a hydrogen atmosphere, the biomass-based fuel precursor undergoes a hydrodeoxygenation reaction by the combined action of a hydrogenation catalyst and a molecular sieve (for example, 0.5 MPa, 1 MPa, 1.5 MPa, 2 MPa, 2.5 MPa, or 3 MPa, etc.). The hydrodeoxygenation reaction time is 1-12 hours (for example, 1 hour, 2 hours, 4 hours, 6 hours, 8 hours, 10 hours, or 12 hours, etc.), and the temperature is 160-200°C (for example, 160°C, 170°C, 180°C, 190°C, or 200°C, etc.). As a result, the biomass-based fuel has a high yield, mild reaction conditions, a simple reaction process, few by-products, and low product separation and purification costs, making it suitable for large-scale application.

[0083] Preferably, the hydrogenation catalyst includes at least one of Pd / C (palladium-supported carbon), Rh / C (rhodium-supported carbon), Pt / C (platinum-supported carbon), Pd / Fe2O3 (palladium-supported ferric oxide), and Pd / TiO2 (palladium-supported titanium dioxide), and the molecular sieve includes at least one of ZSM-5, HY, H-β, Pt / HY (platinum-supported HY molecular sieve), and Pt / H-β (platinum-supported H-β molecular sieve). Thus, the above hydrogenation catalyst and molecular sieve cooperate with each other to effectively improve the yield of biomass-based fuel precursors.

[0084] For example, in a hydrogen atmosphere, in a solvent of cyclohexane and / or n-hexane, the biomass-based fuel precursor is subjected to a hydrodeoxygenation reaction by the combined action of a hydrogenation catalyst and a molecular sieve.

[0085] In one embodiment, the biomass-based fuel precursor is subjected to a hydrodeoxygenation reaction, comprising: mixing the biomass-based fuel precursor, hydrazine hydrate, and a high-boiling-point alcohol solution, heating and refluxing, generating a hydrazone, and then distilling off water and excess hydrazine to obtain an intermediate product; mixing the intermediate product with a strong base and heating it, and when the temperature reaches 195-205°C (for example, 195°C, 200°C, or 205°C, etc.), refluxing for 5-6h (for example, 5h or 6h, etc.), and then conducting a hydrogenation reaction to obtain the biomass-based fuel.

[0086] It is understandable that the product obtained by mixing and heating the biomass-based fuel precursor, hydrazine hydrate and a high-boiling-point alcohol solution can be detected by gas chromatography. When the formation of hydrazone is detected, the water and excess hydrazine are evaporated; the strong base includes a base and / or a Lewis base that can be completely ionized when dissolved in water, and the high-boiling-point alcohol solution refers to an alcohol solution with a boiling point greater than 230°C.

[0087] Exemplarily, the biomass-based fuel precursor, hydrazine hydrate and a high-boiling-point alcohol solution are mixed and heated to 150° C. and refluxed for 4 to 8 hours to generate a hydrazone.

[0088] Exemplarily, the biomass-based fuel precursor is subjected to a hydrodeoxygenation reaction, comprising: mixing the biomass-based fuel precursor with a high-boiling-point alcohol solution, slowly adding hydrazine hydrate using a constant-pressure dropping funnel, stirring and heating to 150°C and reflux for 4 hours, then changing the reflux device to a diversion device, distilling off excess hydrazine hydrate, then changing the reflux device to a reflux device, and connecting an external gas buffer bottle, adding alkali through a feeding funnel, stirring and heating to 195-205°C and reflux for 5-6 hours, stopping the reaction and cooling the solution until there are no obvious bubbles, and obtaining a biomass-based fuel.

[0089] Illustratively, the high-boiling point alcohol solution includes diethylene glycol and / or triethylene glycol, the base includes at least one of potassium hydroxide, sodium hydroxide, potassium tert-butoxide and sodium ethoxide, wherein potassium tert-butoxide and sodium ethoxide are Lewis bases, and the hydrazine hydrate includes hydrazine hydrate 50wt% (referring to the mass fraction of hydrazine in hydrazine hydrate is 50wt%) and / or hydrazine hydrate 80%wt (referring to the mass fraction of hydrazine in hydrazine hydrate is 80wt%).

[0090] Exemplarily, the conditions for the hydrogenation reaction include at least one of the following: a hydrogen pressure of 0.5-3 MPa;

[0091] The hydrogenation reaction time is 1-12 hours; the temperature is 80-120° C.; and the hydrogenation catalyst includes at least one of Pd / C, Rh / C, Pt / C, Pd / Fe2O3 and Pd / TiO2.

[0092] For example, after the hydrogenation reaction is completed, a mixed liquid containing biomass-based fuel is obtained, deionized water is added to the mixed liquid, and then dichloromethane is added to extract three times. The three extracts are collected and the solvent is removed by rotary evaporation to obtain a crude product, and then the crude product is recrystallized by methanol to obtain a biomass-based fuel with higher purity.

[0093] In one embodiment, a method for preparing a biomass-based fuel includes: 1. copolymerizing isophorone and terpinene in a solvent under ultraviolet light irradiation and in the presence of a photocatalyst to obtain a biomass-based fuel precursor; 2. hydrodeoxygenating the biomass-based fuel precursor in a solvent such as cyclohexane or n-hexane in a hydrogen atmosphere using a hydrogenation catalyst and a molecular sieve to obtain the biomass-based fuel; wherein the hydrogen pressure is 0.5-3 MPa, the hydrodeoxygenation reaction time is 1-12 hours, and the temperature is 160-200°C. It should be noted that the ultraviolet light irradiation, isophorone, terpinene, photocatalyst, solvent in step 1, biomass-based fuel precursor, etc. are consistent with the previous description and are not further elaborated here.

[0094] In another embodiment, the preparation method of biomass-based fuel includes: 1. Under ultraviolet light irradiation and in the presence of a photocatalyst, isophorone and terpinene are copolymerized in a solvent to obtain a biomass-based fuel precursor; 2. The biomass-based fuel precursor is mixed with a high-boiling point alcohol solution, hydrazine hydrate is slowly added using a constant pressure dropping funnel, and the mixture is stirred and heated to 150°C and refluxed for 4 hours. The reflux device is then changed to a diversion device to evaporate excess hydrazine hydrate, and then changed to a reflux device again, and an external gas buffer bottle is connected. Alkali is added through an addition funnel, and the mixture is stirred and heated to 195-205°C and refluxed for 5-6 hours. When the solution has no obvious bubbles, the reaction is stopped and the temperature is cooled to obtain a biomass-based fuel. It should be noted that the ultraviolet light irradiation, isophorone, terpinene, photocatalyst, solvent in step 1, biomass-based fuel precursor, etc. are consistent with the previous description and will not be described in detail here.

[0095] The biomass-based fuel of the embodiment of the present application can be synthesized in two steps through heterogeneous photocatalytic cycloaddition and hydrodeoxygenation at room temperature and pressure. The preparation method has high yield, mild reaction conditions, simple reaction process, few by-products, low cost of product separation and purification, and is suitable for large-scale application.

[0096] In a fifth aspect, the present application provides an aerospace fuel, including the biomass-based fuel described above, and / or, including the biomass-based fuel prepared by the preparation method described above.

[0097] It will be understood that aerospace fuel includes aerospace fuel suitable for use in spacecraft, and / or aviation fuel suitable for use in aircraft.

[0098] For example, aerospace fuel can be either solid fuel or liquid fuel. Taking solid fuel as an example, in addition to the biomass-based fuel mentioned above, solid fuel also includes adhesives, curing agents and other components that conventional solid fuels should have, which will not be elaborated here.

[0099] In some embodiments of the present invention, aerospace fuels may be used in aerospace vehicles, such as airplanes and the like.

[0100] The present application will be further described below in conjunction with specific embodiments. It should be noted that the following examples are only used to explain the present application and are not to be construed as limiting the present application. In the absence of conflict, the following embodiments and features in the embodiments may be combined with each other.

[0101] Example 1

[0102] The method for preparing biomass-based fuel comprises the following steps:

[0103] Step 1: Prepare biomass-based fuel precursors

[0104] In a 50 mL single-necked glass reactor, 5 mL (4.2 g) of isophorone and 5 mL (4.08 g) of γ-terpinene were added, followed by 10 mL of chromatographically pure anhydrous methanol. Nitrogen was bubbled through the reactor under stirring for 1 hour. A condenser was then connected and sealed. The condenser was opened to maintain the copolymerization temperature at 20°C. A 365 nm LED light was then used to illuminate the reactor for 24 hours to obtain a reaction solution. The reaction solution was analyzed by gas chromatography-mass spectrometry to characterize the product and calculate the yield. The reaction solution was collected in a 500 mL rotary flask, and the solvent was evaporated using a rotary evaporator to obtain a concentrated solution containing the biomass-based fuel precursor. The concentrated solution was analyzed by gas chromatography.

[0105] Step 2: Prepare biomass-based fuel intermediates using biomass-based fuels

[0106] 20 mL of the concentrate was placed in a 500 mL three-necked flask, 200 mL of diethylene glycol was added and mixed uniformly, 20 mL of hydrazine hydrate (80 wt %) was then slowly added using a constant pressure dropping funnel, and the mixture was stirred and heated to 150 ° C and refluxed for 4 h. The device was then converted into a splitter to distill off excess hydrazine hydrate, and then converted into a reflux device and an external gas buffer bottle. 10 g of KOH was added through an addition funnel, and the mixture was stirred and heated to 205 ° C. When the solution had no obvious bubbles, the reaction was stopped and the temperature was lowered. The solution obtained after the reaction was added to 100 mL of deionized water, and then extracted three times with dichloromethane, using 100 mL of dichloromethane each time. The three extracts were collected and the solvent was removed by rotary evaporation to obtain a crude product, which was then recrystallized from methanol to obtain a high-purity biomass-based fuel intermediate. The product was analyzed by gas chromatography-mass spectrometry, infrared spectrometry, and nuclear magnetic resonance spectrometry to determine the product structure and purity.

[0107] Step 3: Prepare biomass-based fuel using biomass-based fuel intermediates

[0108] Take 20g of biomass-based fuel intermediate in a 200mL hydrogenation kettle, add 100mL of cyclohexane and mix evenly, add 5%wt Pd / C (5% Pd) of the concentrate, and seal the hydrogenation kettle after mixing. After replacing with 3Mpa nitrogen three times, replace it with 3Mpa hydrogen three times, and finally inject 3Mpa hydrogen into the hydrogenation kettle, seal it, start stirring, set the temperature program to rise to 80°C at 5°C / min, and then react at a constant temperature for 6h. During the hydrogenation, observe the pressure gauge frequently. When the pressure in the hydrogenation kettle drops sharply, replenish the pressure to 3Mpa with hydrogen. Take samples from the sampling port every 1h and use chromatography to measure the progress of the hydrogenation reaction. When the raw material conversion rate exceeds 90% and the pressure in the hydrogenation kettle no longer changes significantly, stop heating, let the hydrogenation kettle cool naturally, and release the pressure after it drops to room temperature. Take out the reaction liquid, centrifuge to remove the Pd / C catalyst, and then remove the solvent by rotary evaporation to obtain a crude product. The crude product is then subjected to reduced pressure distillation to obtain a high-purity biomass-based fuel product. The product was analyzed using gas chromatography-mass spectrometry, infrared spectrometer and nuclear magnetic resonance spectrometer to determine the product structure and purity.

[0109] Example 2-16

[0110] The methods for preparing biomass-based fuels in Examples 2-16 are basically the same as those in Example 1, except for the configuration of terpinene, solvent type, cycloaddition reaction light intensity, cycloaddition temperature, or cycloaddition reaction time in step 1. The specific conditions are shown in Table 1 below. The yields of the biomass-based fuel precursors obtained in Examples 1-16 are also shown in Table 1 below:

[0111] Table 1

[0112]

[0113]

[0114] Example 17

[0115] The method for preparing biomass-based fuel comprises the following steps:

[0116] Step 1: Prepare biomass-based fuel precursors

[0117] In a 200 mL single-mouth glass reactor, 25 mL (22 g) of isophorone and 25 mL (20 g) of β-terpinene were added, followed by 50 mL of methanol. Nitrogen was bubbled through the reactor under stirring for 1 hour, and then a condenser was connected and sealed. The condenser was turned on to keep the copolymerization temperature at 20°C. The reactor was irradiated with a 365 nm LED lamp for 24 hours to obtain a reaction solution. The reaction solution was analyzed by gas chromatography-mass spectrometry to characterize the product and calculate the reaction product yield. The reaction solution was collected in a 500 mL rotary evaporator, and the solvent was evaporated using a rotary evaporator to obtain a concentrated solution containing the biomass-based fuel precursor. The concentrated solution was analyzed by gas chromatography.

[0118] Step 2: Prepare biomass-based fuel using biomass-based fuel precursors

[0119] Take 20g of the concentrate in a 200mL hydrogenation kettle, add 100mL of cyclohexane and mix evenly, add 5%wt Pd / C (5% Pd) of the concentrate, and seal the hydrogenation kettle after mixing. After replacing with 3Mpa nitrogen three times, replace it with 3Mpa hydrogen three times, and finally inject 3Mpa hydrogen into the hydrogenation kettle, seal it, start stirring, set the temperature program to increase the temperature to 80°C at 5°C / min, and then react at a constant temperature for 6h. Observe the pressure gauge frequently during hydrogenation. When the pressure in the hydrogenation kettle drops sharply, replenish the pressure to 3Mpa with hydrogen. Take samples from the sampling port every 1h and use chromatography to measure the progress of the hydrogenation reaction. When the raw material conversion rate exceeds 90% and the pressure in the hydrogenation kettle no longer changes significantly, stop heating, let the hydrogenation kettle cool naturally, and release the pressure after it drops to room temperature. Take out the reaction solution, centrifuge to remove the Pd / C catalyst, and then remove the solvent by rotary evaporation to obtain a crude product. The crude product is then subjected to reduced pressure distillation to obtain a high-purity biomass-based fuel product. The product was analyzed by gas chromatography-mass spectrometry, infrared spectrometer and nuclear magnetic resonance spectrometer to determine the product structure and product purity. The gas chromatography-mass spectrometry results of the biomass-based fuel in this embodiment are as follows: Figure 2 As shown, the gas chromatography-mass spectrometry ion peak distribution diagram is as follows Figure 3 As shown, the infrared spectrum is as Figure 4 As shown, the nuclear magnetic resonance hydrogen spectrum is as follows Figure 5 shown.

[0120] Example 18

[0121] The method for preparing biomass-based fuel in this embodiment is basically the same as that in Example 1, except that the mass of the photocatalyst accounts for 0.5 wt % of the total mass of isophorone and β-terpinene. In this embodiment, the yield of the biomass-based fuel precursor is 20%.

[0122] Example 19

[0123] The method for preparing biomass-based fuel in this embodiment is basically the same as that in Example 1, except that the mass of the photocatalyst accounts for 15 wt % of the total mass of isophorone and β-terpinene. In this embodiment, the yield of the biomass-based fuel precursor is 12%.

[0124] The basic principles of the present application have been described above in conjunction with specific embodiments. However, it should be noted that the advantages, strengths, and effects mentioned in this application are merely illustrative and not restrictive, and it should not be assumed that these advantages, strengths, and effects are required of each embodiment of this application. In addition, the specific details disclosed above are merely illustrative and facilitating understanding, and are not restrictive. The above details do not limit this application to necessarily being implemented using the above specific details.

[0125] The above description has been provided for the purpose of illustration and description. Furthermore, this description is not intended to limit the embodiments of the present application to the forms disclosed herein. Although a number of example 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 biomass-based fuel precursor, characterized in that: Including at least one of the structural formulas shown in formula (1) to formula (11):

2. The biomass-based fuel precursor according to claim 1, characterized in that The biomass-based fuel precursor includes the structural formulas shown in formulas (4) to (7), and the molar fractions of the structural formulas shown in formulas (4) to (7) are respectively 30% to 40% for formula (4), 40% to 50% for formula (5), and 60% to 70% for formula (6). 10% to 20%, and formula (7) 3% to 6%.

3. A method for preparing a biomass-based fuel precursor, characterized in that: include: mixing isophorone, terpinene and a solvent to obtain a mixed solution; The mixed solution is irradiated with ultraviolet light to cause an intermolecular [2+2] cycloaddition reaction between isophorone and terpinene to obtain the biomass-based fuel precursor.

4. The method for preparing a biomass-based fuel precursor according to claim 3, characterized in that: The terpinene includes at least one of β-terpinene, γ-terpinene and δ-terpinene; Preferably, the molar ratio of isophorone to terpinene is 1:(1-4); Preferably, before the intermolecular [2+2] cycloaddition reaction occurs, an inert gas is introduced into the mixed solution for 0.5 to 2 hours.

5. The method for preparing a biomass-based fuel precursor according to claim 3, characterized in that: The intermolecular [2+2] cycloaddition reaction is carried out at a temperature of 0-40°C and a time of 1-24h; Preferably, the wavelength range of the ultraviolet light is 320-390 nm; Preferably, the intensity of the ultraviolet light is 130-220 mW / cm 2 ; Preferably, the solvent comprises at least one of methanol, ethanol, isopropanol, acetonitrile and dichloromethane; Preferably, in the mixed solution, the mass content of the solvent is 10 to 50 wt%.

6. A biomass-based fuel, characterized in that: Including at least one of the structural formulas shown in formula (12) to formula (18):

7. A method for preparing biomass-based fuel, characterized in that: include: subjecting the biomass-based fuel precursor according to claim 1 or 2 to a hydrodeoxygenation reaction to obtain the biomass-based fuel; and / or, The biomass-based fuel is obtained by subjecting the biomass-based fuel precursor prepared by the preparation method according to any one of claims 3 to 6 to a hydrodeoxygenation reaction.

8. The preparation method according to claim 7, characterized in that The step of causing the biomass-based fuel precursor to undergo a hydrodeoxygenation reaction comprises: In a hydrogen atmosphere, the biomass-based fuel precursor undergoes a hydrodeoxygenation reaction by the combined action of a hydrogenation catalyst and a molecular sieve, the hydrogen pressure is 0.5-3 MPa, the hydrodeoxygenation reaction time is 1-12 hours, and the temperature is 160-200°C; Preferably, the hydrogenation catalyst includes at least one of Pd / C, Rh / C, Pt / C, Pd / Fe2O3, and Pd / TiO2, and the molecular sieve includes at least one of ZSM-5, HY, H-β, Pt / HY, and Pt / H-β.

9. The preparation method according to claim 7, characterized in that The step of causing the biomass-based fuel precursor to undergo a hydrodeoxygenation reaction comprises: The biomass-based fuel precursor, hydrazine hydrate and a high-boiling-point alcohol solution are mixed and heated under reflux to generate hydrazone, and then water and excess hydrazine are distilled off to obtain an intermediate product; The intermediate product is mixed with a base and heated, and when the temperature reaches 195-205° C., refluxed for 5-6 hours and then subjected to hydrogenation reaction to obtain the biomass-based fuel; Preferably, the biomass-based fuel precursor, hydrazine hydrate and high-boiling-point alcohol solution are mixed and heated to 150° C. and refluxed for 4 to 8 hours to generate hydrazone; Preferably, the high-boiling-point alcohol solution comprises diethylene glycol and / or triethylene glycol, the base comprises at least one of potassium hydroxide, sodium hydroxide, potassium tert-butoxide and sodium ethoxide, and the hydrazine hydrate comprises 50 wt% hydrazine hydrate and / or 80% wt hydrazine hydrate; Preferably, the conditions for the hydrogenation reaction include at least one of the following: The hydrogen pressure is 0.5-3MPa; The hydrogenation reaction time is 1-12h; Temperature is 80-120℃; The hydrogenation catalyst includes at least one of Pd / C, Rh / C, Pt / C, Pd / Fe2O3 and Pd / TiO2.

10. An aerospace fuel, characterized in that The biomass-based fuel comprises the biomass-based fuel according to claim 6, and / or the biomass-based fuel prepared by the preparation method according to any one of claims 7 to 9.

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