Preparation method of high-density coal-based jet fuel

Abstract

The invention discloses a preparation method of high-density coal-based jet fuel. The method comprises the following specific steps: 1, reacting indene with a phenol-containing raw material under the catalysis of an acid catalyst to generate a compound with a tricyclic structure; and 2, hydrogenating the compound with the tricyclic structure in a hydrogenation kettle or a fixed bed under the action of a metal catalyst to generate the high-density coal-based jet fuel, the phenol-containing raw material 2 is one of phenol, o-methylphenol, p-methylphenol, m-methylphenol, carbolic oil and crude phenol. The high-density coal-based jet fuel can be completely prepared from indene extracted from high-temperature coal tar components and phenol-containing raw materials in a high-yield mode through a two-step method, the density of the high-density coal-based jet fuel is larger than 0.90 g / mL, and the high-density coal-based jet fuel is an aviation kerosene alkane compound excellent in performance; according to the whole route, coal tar components (crude phenol / carbolic oil and the like) are used as raw materials, and the method is wide in raw material source, low in cost and more beneficial to industrial production.

Description

Technical Field

[0001] The invention relates to the technical field of compound organic synthesis, and in particular to a method for preparing high-density coal-based jet fuel. Background Art

[0002] High-density hydrocarbon fuels usually refer to artificially synthesized fuels with a density greater than 0.80 g / cm 3 Alkane fuels provide important power guarantees for various aerospace vehicles such as missiles, rockets and fighter jets, and are the research focus in the field of propellants. At present, the main source of jet fuel is oil, and oil resources are becoming increasingly depleted. In particular, China has become a net importer of crude oil since the 1990s, and its dependence on foreign crude oil has exceeded 55%. Therefore, how to ensure my country's growing demand for jet fuel has become an important research topic in the post-oil era. With the development of aviation technology, the continuous upgrading of engines, and the increasing requirements for environmental protection at home and abroad. In response to the differentiated needs of my country's military and civil aircraft for fuel quality indicators, the system refers to the international general jet fuel standard system, and scientifically adjusts and optimizes the key performance parameters of kerosene fractions (including density, freezing point, lubricity and thermal oxidation stability) to develop qualified products that meet the technical specifications of aviation fuel. From a global perspective, the process used to produce jet fuel mainly depends on the nature of the raw materials. Therefore, in order to further expand this market share and improve profitability, seeking low-sulfur, low-corrosive and high-stability jet fuel is the ultimate goal.

[0003] In addition to the indene-rich (C 9 H 8 , 2%-5%), phenol (C 6 H 5OH (5%-10%) is also a key phenolic component. Phenolic oil is a fraction cut during the distillation of coal tar, with a boiling range generally between 170-210 °C. It is a product obtained by further rectifying the crude tar recovered from coke oven gas. Its components are mainly phenolic compounds, among which phenol accounts for 15-18%, cresols (o-methyl, m-methyl, and p-methyl) account for 65-70%, dimethylphenols and ethylphenols account for about 5%. In addition to phenolic substances, it also contains a small amount of naphthalene, tridecane, hexadecane, quinoline, etc. Crude phenol is a product obtained by refining phenolic oil through distillation, separation, etc., and is a high-quality phenolic product containing phenol and cresols. The bicyclic aromatic structure of indene and the hydroxyaromatic ring structure of phenol have complementary chemical properties: 1. Indene: The fused bicyclic system (benzene ring + five-membered ring) can be expanded into a polycyclic structure through reactions such as cycloaddition and polycondensation; 2. Phenol: The hydroxyl functional group can not only participate in deoxygenation to generate aromatic precursors but also act as a hydrogen bond donor to regulate the reaction path. In existing processes, the two are mostly separated for the synthesis of phenolic resins or blended into low-value fuels, and their synergistic effect has not been utilized to construct a high-density fuel skeleton. Developing an indene-phenol coupling conversion technology can simultaneously improve the utilization rate of coal tar resources and the added value of products.

[0004] The current research on the co-conversion of aromatics and phenols faces the following core challenges: 1. Reaction path conflict: The ring expansion of indene requires an acidic catalytic environment, while the deoxygenation of phenol (such as hydrodeoxygenation, HDO) depends on metal catalysts, and traditional single-functional catalysts are difficult to be compatible; 2. Oxygen element interference: The hydroxyl group in phenol is prone to cause coking (such as generating macromolecules such as diphenyl ethers through condensation) or poisoning acidic sites; 3. Uncontrollable product structure: Disordered polycyclic aromatic hydrocarbons (such as pyrene, anthracene, etc.) are easily generated in the mixed reaction system, resulting in limited increase in fuel density and elevated freezing point. Therefore, to solve the above technical problems, a new method for preparing high-density coal-based jet fuel is needed. Summary of the Invention

[0005] The object of the present invention is to provide a method for preparing high-density coal-based jet fuel, which has simple steps and high yield. Subsequently, indene reacts with crude phenol / phenolic oil, and after hydrogenation and purification, high-density coal-based jet fuel is obtained.

[0006] To achieve the above object, the technical solution adopted by the present invention is as follows: A method for preparing high-density coal-based jet fuel, comprising the following steps:

[0007] S1. Dissolve indene compound 1 and phenolic raw material 2 in an organic solvent, and react under the catalysis of an acidic catalyst to generate a compound 3 with a tricyclic structure; the phenolic raw material 2 is one of phenol, o-methylphenol, p-methylphenol, m-methylphenol, phenolic oil, and crude phenol;

[0008]

[0009] In the formula, R is selected from hydrogen or methyl;

[0010] S2. Dissolve the compound 3 with a tricyclic structure in an alkane solvent and carry out hydrogenation in a hydrogenation autoclave or a fixed bed under the condition of a metal catalyst to produce a high-density coal-based jet fuel 4;

[0011]

[0012] In the formula, R is selected from hydrogen or methyl.

[0013] Preferably, in step S1, the reaction temperature is 60 - 160 °C and the reaction time is 6 - 24 h.

[0014] Preferably, in step S1, the acidic catalyst is a homogeneous catalyst or a heterogeneous catalyst. The homogeneous catalyst is concentrated sulfuric acid or trifluoroacetic acid, and the heterogeneous catalyst is Nafion, T - 62MP, Amberlyst15, AlCl 3 , CD750, CD250, H 3 O 40 PW 12 .xH 2 O, H 4 [Si(W 3 O 10 ) 4 ·xH 2 O, or one of them.

[0015] Preferably, in step S1, the dosage of the homogeneous catalyst is 15% of the 2 - molar amount of the phenol-containing raw material, and the dosage of the heterogeneous catalyst is 15% of the 2 - mass of the phenol-containing raw material.

[0016] Preferably, in step S1, the organic solvent is selected from one or more of dichloromethane, dichloroethane, n - hexane, cyclohexane, n - octane, ethyl acetate, cyclohexanone, toluene, dimethyl sulfoxide, N,N - dimethylformamide, acetone, N - methylpyrrolidone, propylene carbonate, dimethyl carbonate, petroleum ether, and the concentration range of the phenol-containing raw material 2 is 0.5 - 1 mol / L.

[0017] Preferably, in step S2, the mass ratio of the metal catalyst dosage to the compound 3 with a tricyclic structure is (0.01 - 1):1.

[0018] Preferably, in step S2, the metal catalyst is selected from one of commercial Raney nickel, commercial Raney cobalt, Pt / C, Pd / C, Ru / C, Rh / C, X 1 RuX 2 M / H - Beta, where the active metal loading of Pt / C, Pd / C, Ru / C, Rh / C is 3 - 8 wt%, X 1 and X 2respectively represent Ru and M in X 1 RuX 2 the mass percentage of M / H-Beta, X 1 is 1 - 5%, X 2 is 0.5 - 10%, and M is one of Ni, Co, Cu, and Zn.

[0019] Preferably, in step S2, the alkane solvent is cyclohexane or n-hexane, the concentration of compound 3 with a tricyclic structure in the hydrogenation autoclave is 0.01 - 10 mol / L, and the concentration of compound 3 with a tricyclic structure in the fixed bed is 1 wt% - 20 wt%.

[0020] Preferably, in step S2, when the hydrogenation reaction is carried out in a hydrogenation autoclave, the reaction temperature is 160 - 300 °C, the reaction time is 4 - 12 h, and the hydrogen pressure is 1 - 6 MPa; when the hydrogenation reaction is carried out in a hydrogenation fixed bed, the average reaction temperature is 160 - 300 °C, the reaction pressure is 0.5 - 4 MPa, the molar ratio of hydrogen to compound 3 with a tricyclic structure is (200 - 1000):1, and the liquid hourly space velocity is 0.1 - 1 h -1 .

[0021] The present invention proposes a two-step collaborative strategy of "ring expansion - hydrodeoxygenation", relying on the following key technological breakthroughs: 1. Application of bifunctional catalysts: Construct a bimetallic structure catalyst (such as Ru-Ni@H-Beta), use relatively inexpensive metals for efficient full hydrogenation, and operate stably on a fixed bed for 200 h, which provides the possibility for large-scale production. 2. Oxygen-directed conversion mechanism: By regulating the solvation effect of the reaction medium (such as supercritical CO 2 ), quickly remove the H 2 O generated by the deoxygenation of phenol from the system to avoid side reactions of hydroxyl condensation;

[0022] The present invention realizes for the first time the synergistic high-value conversion of indene in coal tar and phenolic raw materials. The fuel density of the product can reach 0.94 - 0.95 g / cm 3 , the freezing point is below -75 °C, opening up a new paradigm for the development of coal-based special fuels; the phenolic raw materials also include crude phenol and phenolic oil and other coal chemical crude products, which have industrial production significance. Extracting phenolic compounds and indene from the phenolic oil component in high-temperature coal tar for controllable ring expansion reaction and then hydrogenation treatment to produce a coal-based high-density jet fuel with some properties comparable to JP-10 is a new production process with good economic benefits and market prospects.

[0023] Compared with the prior art, the present invention has the following beneficial effects:

[0024] 1. The present invention can completely achieve the preparation of high-density coal-based jet fuel with high yields from indene and phenol-containing raw materials extracted from high-temperature coal tar components through a two-step method. Its density is greater than 0.90 g / mL, and it is an aviation kerosene alkane compound with relatively excellent performance.

[0025] 2. The entire route uses coal tar components (such as crude phenol / phenol oil, etc.) as raw materials, which has a wide range of raw material sources, low costs, and is more conducive to industrial production. BRIEF DESCRIPTION OF THE DRAWINGS

[0026] Figure 1 . MS spectrum of product 3 prepared in Example 32;

[0027] Figure 2 . GC spectrum of product 3 prepared in Example 32;

[0028] Figure 3 . Product 3 prepared in Example 32 1 H NMR spectrum;

[0029] Figure 4 . Product 3 prepared in Example 32 13 C NMR spectrum;

[0030] Figure 5 . GC spectrum of the product prepared with p-cresol as the raw material in Example 36;

[0031] Figure 6 . GC spectrum of the product prepared with m-cresol as the raw material in Example 37;

[0032] Figure 7 . GC spectrum of the product prepared with o-cresol as the raw material in Example 35;

[0033] Figure 8 . Product 4 prepared in Example 56 13 C NMR spectrum;

[0034] Figure 9 . MS spectrum of hydrogenated product 4 prepared in Example 56;

[0035] Figure 10 . GC spectrum of hydrogenated product 4 prepared in Example 56;

[0036] Figure 11 . Hydrogenated product 4 prepared in Example 56 1 H NMR spectrum;

[0037] Figure 12 . Hydrogenated product 4 prepared with crude phenol as the raw material 1 H NMR spectrum;

[0038] Figure 13 1H NMR spectrum of the hydrogenation product 4 prepared from crude phenol 13 C NMR spectrum Detailed implementation mode

[0039] The present invention will be further described in detail below with reference to the accompanying drawings and specific embodiments

[0040] In the following examples, unless otherwise specified, the reagents used can be purchased commercially or obtained in the manner reported in known literature

[0041] Example

[0042] A preparation method of high-density aviation fuel, comprising the following steps

[0043] S1. Dissolve indene compound 1 (1 mmol, 0.116 g) and phenolic raw material 2 (1 mmol, 0.084 g) in 1 mL of organic solvent (when phenolic raw material 2 is phenol oil or crude phenol, the main component is methylphenol, and the molecular weight is calculated as 108 when calculating the molar amount), and react under the catalysis of an acidic catalyst to generate a compound 3 with a tricyclic structure; the dosage of the heterogeneous acidic catalyst is 15% of the mass of phenolic compound 2; the dosage of the homogeneous acidic catalyst is 15% of the molar amount of phenolic compound 2; the reaction temperature is 60-160 °C, and the reaction time is 6-24 h

[0044]

[0045] S2. When the hydrogenation reaction is carried out in a reaction kettle, dissolve the compound 3 with a tricyclic structure (2.1 g, 10 mmol) in 20 mL of alkane solvent, and react under the catalysis of 420 mg of metal catalyst (active metal loading 5 wt%) at 160-300 °C and 3 MPa hydrogen pressure for 4-12 h to obtain high-density coal-based jet fuel 4

[0046] When the hydrogenation reaction is carried out in a fixed bed, the reaction conditions are as follows: hydrogen is used as the raw material gas, and a cyclohexane solution containing 1-20% by mass of the compound 3 with a tricyclic structure (2.1 g, 10 mmol) is used as the raw material liquid. The molar ratio of hydrogen to the compound 2 with a tricyclic structure in the reaction is (200-1000):1, the reaction temperature range is 160-300 °C, the reaction pressure is 0.5-4 MPa, and the reaction space velocity is 0.1-1 h -1 . A stainless steel reaction tube is used as the reactor, with an outer diameter of 20 mm, an inner diameter of 8 mm, and a length of 300 mm. The catalyst loading is 0.5 g. After the reaction tail gas is condensed and separated, a Fuli GC9790PLUS gas chromatograph is used for quantitative analysis of the product

[0047]

[0048] Examples 1 - 40 differ in the catalyst, reaction temperature, solvent, and reaction time in step S1. The specific parameters are shown in Table 1 below:

[0049] Table 1. Influence of catalyst, temperature, solvent, and time on the reaction

[0050]

[0051]

[0052]

[0053] It can be seen from the results in Table 1 that the heterogeneous catalysts T - 62MP, Amberlyst15, CD750, CD250, and Nafion show good catalytic performance in the reaction of indene with phenolic raw materials and achieve a yield above the medium level. Among them, Nafion has the best catalytic performance, and the product yield reaches 97% under the condition of 60 °C for 10 h. Through the screening of different solvents, it is found that dichloromethane, ethyl acetate, n - octane, toluene, cyclohexane, N,N - dimethylformamide, and propylene carbonate, etc. have relatively good effects on this reaction. However, considering the environmental friendliness and the ease of subsequent separation and treatment, cyclohexane is selected as the solvent. Through the screening of different reaction times, it is found that prolonging the time will not increase the product yield. The yield of the dimer product is 97% after 10 h of reaction, which is not much different from the results of 12 h and 14 h of reaction.

[0054] Since the service life of the catalyst needs to be investigated in practical applications, the recycling of Nafion was studied with cyclohexane as the solvent at 60 °C for 10 h. After the first reaction, the product and the catalyst will automatically separate into layers. The upper layer is the product, and the lower layer is the catalyst. The product is separated, and the next cycle is continued. It can be seen from the results in Table 2 that the yield of Nafion shows no obvious change after being recycled four times, indicating that this reaction system can be reused.

[0055] Table 2. Recycling experiment of Nafion

[0056]

[0057] The MS spectrum of compound 3 prepared in Example 32 is as Figure 1 shown. It can be seen from the figure that the maximum mass - to - charge ratio of the molecular ion peak of this substance is about m / z = 210. The relative molecular mass of phenol is 84, the relative molecular mass of indene is 116, and the relative molecular mass of compound 3 is 210. Therefore, this product may be the target product 3, and subsequent nuclear magnetic resonance is needed for auxiliary verification.

[0058] The GC chromatogram of Compound 3 prepared in Example 32 is as Figure 2 shown. The gas chromatography was set with an injection port temperature of 270 °C, an initial column oven temperature of 40 °C, a heating rate of 15 °C / min, heated to 280 °C and held for 5 min. The substance eluting at 8.9 min in the GC chromatogram is the internal standard n-tridecane, and the substances eluting at 15.1 / 15.6 min are Compound 3.

[0059] The 1 H NMR spectrum of Compound 3 prepared in Example 32 is as Figure 3 shown. 1 HNMR(600MHz,Chloroform-d)δ7.77–6.57(m,8H),6.19(s,1H),4.59–4.13(m,1H),3.66–2.86(m,2H),2.91–2.41(m,1H),2.44–1.94(m,1H).

[0060] The 13 C NMR spectrum of Compound 3 prepared in Example 32 is as Figure 4 shown. 13 C NMR(151MHz,Chloroform-d)δ154.02,147.36,144.44,137.86,131.08,129.88,129.55,129.45,127.77,127.12,127.09,126.79,126.70,126.61,126.55,126.49,126.46,125.06,125.04,125.00,124.97,124.95,124.92,124.56,124.52,121.16,120.95,116.41,116.39,116.17,115.60,51.02,45.99,36.89,34.62,31.97,31.95.

[0061] The GC chromatogram of the product prepared from p-cresol in Example 36 is as Figure 5 shown. The gas chromatography was set with an injection port temperature of 270 °C, an initial column oven temperature of 40 °C, a heating rate of 15 °C / min, heated to 280 °C and held for 5 min. The substance eluting at 8.9 min in the GC chromatogram is the internal standard n-tridecane, and the substances eluting at 15.6 / 16.1 min are the target products.

[0062] The GC chromatogram of the product prepared from m-cresol in Example 37 is as Figure 6As shown in the figure. The inlet temperature of the gas chromatography was set at 270 °C, the initial temperature of the column oven was set at 40 °C, the heating rate was 15 °C / min, and it was heated to 280 °C and held for 5 min. The substance eluting at 8.9 min in the GC chromatogram was the internal standard n-tridecane, and the substances eluting at 15.8 / 16.3 min were the target products.

[0063] The GC chromatogram of the product obtained from o-cresol as the raw material in Example 35 is as Figure 7 shown. The inlet temperature of the gas chromatography was set at 270 °C, the initial temperature of the column oven was set at 40 °C, the heating rate was 15 °C / min, and it was heated to 280 °C and held for 5 min. The substance eluting at 8.9 min in the GC chromatogram was the internal standard n-tridecane, and the substances eluting at 15.8 / 16.1 min were the target products.

[0064] In Examples 44 - 64, the tricyclic structure compound obtained in Example 32 was hydrogenated in a reaction kettle. The differences were the catalysts, reaction temperatures, solvents, and reaction times in step S2, and the specific parameters are shown in Table 3 below:

[0065] Table 3. Effects of catalysts, temperature, solvents, and time on the hydrogenation reaction (hydrogenation kettle)

[0066]

[0067]

[0068] From the results in Table 3, it can be seen that the hydrogenation capabilities of different metal catalysts are different. Among them, the activities of metals Rh, Pt, Ru, and Pd are relatively good. In the screening of solvents, both n-hexane and cyclohexane have good effects, but because n-hexane has a better effect in the subsequent separation of products, n-hexane was used as the hydrogenation solvent. It should be noted that when the temperature rises to 300 °C, 1Ru0.5M / H-Beta (M is Cu, Co, Zn, Ni) also has a good product yield. Considering the limitation of the reaction temperature of the hydrogenation kettle and the possibility of subsequent large-scale production, a fixed bed was used to further evaluate the hydrogenation performance of this catalyst. In summary, using Ru / C as the catalyst, n-hexane as the solvent at 180 °C in the hydrogenation kettle, the yield after reacting for 8 h is relatively high at 91%, and the optimal conditions for the hydrogenation reaction are obtained.

[0069] It was desired to explore the service life of this catalyst in practical applications. Therefore, using n-hexane as the solvent, the recycling of Ru / C was studied under the condition of reacting at 180 °C for 12 h. From the results in Table 4, it can be seen that the yield of Rh / C did not change significantly after being recycled four times, indicating that this reaction system can be reused.

[0070] Table 4. Hydrogenation cycle experiment

[0071]

[0072] Examples 39 - 112 involve hydrogenating the tricyclic structure - containing compound obtained in Example 32 in a fixed - bed. The differences lie in the catalyst, the concentration of the tricyclic structure - containing compound 3, the reaction temperature, the liquid hourly space velocity, the reaction pressure, and the molar ratio between hydrogen and the tricyclic structure - containing compound 3 (i.e., the hydrogen - to - oil ratio in Table 5) in step S2. The specific parameters are shown in Table 5 below:

[0073] Table 5. Influence of Different Parameters on the Hydrogenation Reaction (Fixed - bed)

[0074]

[0075]

[0076] It can be seen from the results in Table 5 that the hydrogenation capabilities of catalysts with different metal loadings are different. Among them, 1Ru0.5Ni / H - Beta shows relatively good activity. When screening the feed concentration, it is found that the raw material concentration of 5wt% has the best effect and a relatively high conversion rate, which is beneficial to the subsequent product separation. Therefore, a raw material concentration of 5wt% is adopted. By screening different temperatures, when the temperature rises above 260 °C, the yield of the product decreases. Considering energy consumption and the comparison of yields, the present invention selects 260 °C as the optimal reaction temperature. By screening different liquid hourly space velocities, it is found that changing the space velocity does not affect the yield. Considering the possibility of long - term production in this fixed - bed, 0.5 h - 1 is selected. By screening different hydrogen - to - oil ratios, it is found that the hydrogen - to - oil ratio does not affect the yield of this product. Considering raw material economy, a hydrogen - to - oil ratio of 200:1 is selected. By screening different hydrogen pressures, it is found that the yield of the reaction is the highest when the pressure is 3 Mpa. When the pressure is further increased, the product yield remains unchanged. In summary, in the fixed - bed, the catalyst loading is 0.5 g, the temperature is 260 °C, the feed concentration is 5wt%, the liquid hourly space velocity is 0.5 h -1 , the hydrogen pressure is 3 Mpa, the hydrogen - to - oil ratio is 200:1, the yield is relatively high at 92%, and the catalyst life is 200 h, thus obtaining the optimal conditions for the hydrogenation reaction.

[0077] The MS spectrum of the hydrogenation product 4 prepared in Example 56 is as Figure 8 shown. It can be seen from the figure that the maximum mass - to - charge ratio of the molecular ion peak of this substance is m / z = 206. The relative molecular mass of compound 3 is 210, and the relative molecular mass after complete hydro - deoxygenation should be 206. The GC - MS result shows that the maximum molecular weight is 206. Therefore, this product may be the target addition product 4, and NMR is needed for auxiliary verification in the follow - up.

[0078] The GC spectrum of the hydrogenation product 4 prepared in Example 56 is as Figure 9As shown. The inlet temperature of the gas chromatograph was set at 270 °C, the initial temperature of the column oven was set at 40 °C, the heating rate was 15 °C / min, and it was heated to 280 °C and held for 5 min. The substance eluting at 8.9 min in the GC chromatogram was the internal standard n-tridecane, and the substances eluting at 11.3 / 11.5 / 11.8 min were the addition product 4.

[0079] The 1 H NMR spectrum of the hydrogenation product 4 prepared in Example 56 was as Figure 10 shown. 1 H NMR (600 MHz, Chloroform-d) δ 2.46–0.47 (m, 26H).

[0080] The 13 C NMR spectrum of the hydrogenation product 4 prepared in Example 56 was as Figure 11 shown. 13 C NMR (151 MHz, Chloroform-d) δ 55.91–45.51 (m), 43.61–36.87 (m), 33.07–18.88 (m).

[0081] Example 113

[0082] In this example, the tricyclic compound 3 obtained in Example 39 (crude phenol as the phenol-containing raw material) was hydrogenated in a reaction kettle to produce high-density coal-based jet fuel 4. The specific preparation process was as follows: The tricyclic compound 3 (21 g, 0.1 mol) was dissolved in 40 mL of cyclohexane, and under the catalysis of 4.20 g of metal catalyst Pd / C (active metal loading 5 wt%), the reaction was carried out at 220 °C and 4 MPa hydrogen pressure until the hydrogenation was complete. When the hydrogen was insufficient, it was replenished in time to obtain high-density coal-based jet fuel 4.

[0083] The 1 H NMR spectrum of the hydrogenation product 4 prepared in Example 113 was as Figure 12 shown. 1 H NMR (600 MHz, Chloroform-d) δ 2.41–0.47 (m, 26H).

[0084] The 13 C NMR spectrum of the hydrogenation product 4 prepared in Example 113 was as Figure 13 shown. 13 C NMR (151 MHz, Chloroform-d) δ 55.91–45.51 (m), 43.61–36.87 (m), 33.07–18.88 (m).

[0085] The biomass high-density fuels obtained in Example 56 and Example 113 were respectively compared with traditional petroleum-based fuels (JP-10, RJ-4, RJ-4-I, RJ-5, and RJ-7) in terms of properties. It was found that while maintaining key properties such as density, calorific value, and freezing point, the difficulty and cost of synthesis were significantly reduced.

[0086] Table 6. Performance comparison of different fuels

[0087]

[0088] As can be seen from the examples in Table 6, through a two-step method, it is possible to prepare a high-density coal-based jet fuel from indene and phenol-containing raw materials. The density of the prepared high-density coal-based jet fuel 4 is 0.942 g / cm 3 , the calorific value is 48.3 MJ / L, the freezing point is < -80 °C, and the viscosity is 52.1 mPa·s. Some of the performance of the fuel prepared from phenol and crude phenol can be comparable to that of JP-10, and it is an aviation fuel with relatively excellent performance. It should be noted that for the high-density coal-based jet fuel 4 prepared in Example 113, the gas phase proportion of the three-ring structure is 77%, and the gas phase proportion of the four-ring structure is 23%. The entire route uses high-temperature coal tar components as raw materials, which is a new type of green and environmentally friendly route and does not produce harmful substances.

[0089] The above is only a specific embodiment of the present invention, but the protection scope of the present invention is not limited thereto. Any person skilled in the art within the technical scope disclosed by the present invention, any modification, equivalent replacement, and improvement made within the spirit and principle of the present invention should be covered by the protection scope of the present invention.

Claims

1. A method for preparing high-density coal-based jet fuel, characterized in that: The following steps are involved: S1, dissolving an indene compound 1 and a phenol-containing raw material 2 in an organic solvent, and reacting them under the catalysis of an acidic catalyst to generate a compound 3 having a tricyclic structure; the phenol-containing raw material 2 is one of phenol, o-methylphenol, p-methylphenol, m-methylphenol, phenol oil, and crude phenol; In the formula, R is selected from hydrogen or methyl; S2, dissolving the compound 3 having a tricyclic structure in an alkane solvent, and hydrogenating it in a hydrogenation reactor or a fixed bed in the presence of a metal catalyst to generate a high-density coal-based jet fuel 4; In the formula, R is selected from hydrogen or methyl.

2. The method for preparing a high-density coal-based jet fuel according to claim 1, characterized in that: In step S1, the reaction temperature is 60-160° C. and the reaction time is 6-24 h.

3. The method for preparing a high-density coal-based jet fuel according to claim 1, characterized in that: In step S1, the acidic catalyst is a homogeneous catalyst or a heterogeneous catalyst, the homogeneous catalyst is concentrated sulfuric acid or trifluoroacetic acid, and the heterogeneous catalyst is Nafion, T-62MP, Amberlyst15, AlCl3, CD750, CD250, H3O 40 PW 12 .xH2O, H4[Si(W3O 10 )4]·One of xH2O.

4. The method for preparing a high-density coal-based jet fuel according to claim 3, characterized in that: In step S1, the amount of the homogeneous catalyst used is 15% of the molar amount of the phenol-containing raw material 2, and the amount of the heterogeneous catalyst used is 15% of the mass of the phenol-containing raw material 2.

5. The method for preparing a high-density coal-based jet fuel according to claim 1, characterized in that: In step S1, the organic solvent is selected from one or more of dichloromethane, dichloroethane, n-hexane, cyclohexane, n-octane, ethyl acetate, cyclohexanone, toluene, dimethyl sulfoxide, N,N-dimethylformamide, acetone, N-methylpyrrolidone, propylene carbonate, dimethyl carbonate, and petroleum ether, and the concentration range of the phenol-containing raw material 2 is 0.5-1 mol / L.

6. The method for preparing a high-density coal-based jet fuel according to claim 1, characterized in that: In step S2, the mass ratio between the amount of the metal catalyst and the compound 3 having a tricyclic structure is (0.01-1):

1.

7. The method for preparing a high-density coal-based jet fuel according to claim 1, characterized in that: In step S2, the metal catalyst is selected from one of commercial Raney nickel, commercial Raney cobalt, Pt / C, Pd / C, Ru / C, Rh / C, and X1RuX2M / H-Beta, wherein the active metal loading of Pt / C, Pd / C, Ru / C, and Rh / C is 3-8wt%, X1 and X2 respectively represent the mass percentage of Ru and M in X1RuX2M / H-Beta, X1 is 1-5%, X2 is 0.5-10%, and M is one of Ni, Co, Cu, and Zn.

8. The method for preparing a high-density coal-based jet fuel according to claim 1, characterized in that: In step S2, the alkane solvent is cyclohexane or n-hexane, the concentration of the compound 3 having a tricyclic structure in the hydrogenation reactor is 0.01-10 mol / L, and the concentration of the compound 3 having a tricyclic structure in the fixed bed is 1 wt%-20 wt%.

9. The method for preparing a high-density coal-based jet fuel according to claim 1, characterized in that: In step S2, when the hydrogenation reaction is carried out in a hydrogenation reactor, the reaction temperature is 160-300° C., the reaction time is 4-12 h, and the hydrogen pressure is 1-6 MPa; when the hydrogenation reaction is carried out in a hydrogenation fixed bed, the average reaction temperature is 160-300° C., the reaction pressure is 0.5-4 MPa, the molar ratio of hydrogen to the compound 3 having a tricyclic structure is (200-1000): 1, and the liquid volume space velocity is 0.1-1 h -1 .

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