Preparation method of aviation biofuel

Abstract

The invention discloses an aviation biofuel preparation method, which comprises: (1) carrying out a catalytic cracking reaction on oleic acid to obtain pyrolysis oil; (2) carrying out rectification reaction on the pyrolysis oil to obtain rectified light oil; (3) carrying out esterification reaction on the light oil; the aviation biofuel is obtained. According to the method, oleic acid is adopted as a raw material, and the low-cost aviation biofuel is prepared by optimizing the process conditions of high-temperature catalytic cracking, rectification fractionation and esterification reaction under the condition of no hydrogenation. The aviation biofuel prepared by the method meets the standard of aviation biofuel, and is low in technical difficulty and low in cost.

Description

Technical Field

[0001] The invention belongs to the technical field of aviation biofuel, and specifically relates to a method for preparing aviation biofuel. Background Art

[0002] The global aviation industry consumes approximately 1.5-1.7 billion barrels of jet fuel each year, and greenhouse gas emissions from the aviation industry account for 2%-3% of global emissions.

[0003] For the aviation industry, developing biomass energy is a feasible solution, but there are still many issues to be resolved regarding raw materials and costs of aviation biofuels.

[0004] The most commonly used technology for preparing aviation biofuel is to first allow the oil raw materials to be filled with hydrogen, add catalysts, undergo high-temperature catalytic cracking, and then distill and fractionate the intermediate products. However, this depends on operating conditions and the industrial route is expensive.

[0005] Therefore, it is necessary to provide a method for preparing aviation biofuel to solve the above problems. Summary of the invention

[0006] The purpose of the present invention is to provide a method for preparing aviation biofuel. The present invention uses oleic acid (biofat) as a raw material, and optimizes the process conditions of high-temperature catalytic cracking, rectification and fractionation, and esterification reaction without hydrogenation to achieve low-cost preparation of aviation biofuel. The aviation biofuel prepared by the present invention meets the standards of aviation biofuel, and has low technical difficulty and low cost.

[0007] In order to achieve the above object, the present invention is implemented by the following technical solutions: The first aspect of the present invention is to provide a method for preparing aviation biofuel, comprising the following steps: (1) catalytic cracking of oleic acid to obtain cracking oil; (2) subjecting the pyrolysis oil to a distillation reaction to obtain a distilled light oil; (3) subjecting the light oil to an esterification reaction to obtain aviation biofuel.

[0008] As a preferred embodiment, Step (1), using oleic acid as a reactant, adding catalysts LGO (RM) and zeolite for catalytic cracking to obtain cracking oil.

[0009] Oleic acid used in the present invention has a chemical formula of C 18 H 34O2 is a monounsaturated omega-9 fatty acid. Oleic acid has a melting point of 13-14°C, a boiling point of 360°C, a relative density of 0.8935 (20 / 4°C), a vapor pressure of 52 mmHg (37°C), a refractive index of 1.4585-1.4605, and a flash point of 270.1°C. Oleic acid is non-toxic, flammable, and easily soluble in organic solvents such as ethanol, ether, and chloroform, but insoluble in water.

[0010] As a preferred embodiment, Step (1), The mass ratio of the catalyst LGO (RM) to oleic acid is 2.8%-3%:1; the catalyst LGO (RM) of the present invention is an existing catalyst that can be directly purchased; The temperature of the pyrolysis oil collected from the catalytic cracking reaction is 390°C-430°C.

[0011] As a preferred embodiment, In step (1), during the catalytic cracking reaction, the temperature is first raised to 100°C-180°C at a temperature increase of 10°C each time (i.e., the temperature is raised by 10°C each time, and then the temperature is raised after stabilization); then the temperature is raised to 220°C at a temperature increase of 3°C each time; then the temperature is raised to 350°C at a temperature increase of 5°C each time; then the temperature is raised to 390°C-430°C, and the cracking oil is collected within the temperature range of 390°C-430°C.

[0012] As a preferred embodiment, Step (2), adding zeolite to the pyrolysis oil and performing a distillation reaction; the temperature of the light oil collected from the distillation reaction is 210° C.-280° C.

[0013] As a preferred embodiment, In step (2), during the distillation reaction, the temperature is first raised to 50°C, and then raised to 210°C-280°C by 3°C each time, and the light oil distilled is collected within the temperature range of 210°C-280°C.

[0014] As a preferred embodiment, Step (3), adding alcohol and inorganic base to the light oil to carry out esterification reaction, separating alcohol from the product after the esterification reaction, and obtaining the aviation biofuel.

[0015] As a preferred embodiment, Step (3), The alcohol is selected from methanol; The inorganic base is selected from KOH; The mass ratio of the alcohol to the light oil is 18%-22%:1; The mass ratio of the inorganic alkali to the light oil is 5%-7%:1, preferably 6%-7%:1.

[0016] As a preferred embodiment, Step (3), The temperature of the esterification reaction is 60°C to 65°C; The esterification reaction time is 1-2h.

[0017] The esterification reaction is a reaction between terminal carboxyl groups and hydroxyl groups to generate ester groups and water under certain conditions, which can promote the acid-alcohol reaction.

[0018] As a preferred embodiment, The aviation biofuel has a color of transparent or transparent light yellow, a flash point of ≥38° C., a pour point of ≤-50° C., a kinematic viscosity of ≥1.25 mm2 / s, and an acid value of ≤1.7 KOHmg / g.

[0019] In the prior art, there is no report on the preparation of aviation biofuel using oleic acid as raw material. The present invention is the first to achieve a technical breakthrough in the preparation of aviation biofuel using oleic acid (bio-fat) as raw material without hydrogenation. The present invention finds that the catalyst LGO (RM) can be used in the catalytic cracking of oleic acid, and by optimizing the process conditions of oleic acid catalytic cracking, rectification and fractionation, esterification reaction, etc., the preparation of low-cost aviation biofuel is achieved. Therefore, the aviation biofuel prepared by the present invention meets the standards of aviation biofuel, and has low technical difficulty and low cost.

[0020] The beneficial effects of the present invention are: The method for preparing aviation biofuel provided by the present invention is expected to replace traditional petroleum-based aviation kerosene, thereby reducing carbon emissions.

[0021] The method for aviation biofuel provided by the present invention uses oleic acid (bio-fat) as a raw material, which is easy to obtain and has low cost, and can solve the problem of high price of existing aviation biofuel.

[0022] The aviation biofuel method provided by the present invention has simple operation, simple device and low technical difficulty. DETAILED DESCRIPTION

[0023] The present invention is further described in detail below through specific implementation modes.

[0024] The purchase source of catalyst LGO (RM) (available on the market, produced by PetroChina Lanzhou Petrochemical Company).

[0025] Example 1

[0026] The method for preparing aviation biofuel of the present invention comprises the following steps: (1) Catalytic cracking reaction Oleic acid is selected as the reactant, and the catalyst LGO (RM) and zeolite are added and stirred. At 100℃~180℃, the temperature is increased by 10℃ each time (i.e., the temperature is increased by 10℃ each time, and the temperature is increased after stabilization). Before it reaches about 180℃ to 220℃, the temperature needs to be increased by 3℃ each time (i.e., the temperature is increased by 3℃ each time, and the temperature is increased after stabilization); then the temperature is increased to 350℃ by 5℃ each time (i.e., the temperature is increased by 5℃ each time, and the temperature is increased after stabilization); then the temperature is increased to 390℃-430℃, and the cracking oil is collected within the temperature range of 390℃-430℃; wherein, the mass ratio of the catalyst LGO (RM) to oleic acid is 3%:1, the reactants are stably produced at about 390℃, and the product collection ends at about 430℃. When the cracking oil output is basically finished. Turn off the digital display constant temperature electric heating jacket and cool to room temperature. The remaining heavy oil is recovered through the waste liquid recovery barrel.

[0027] (2) Distillation reaction (distillation fractionation reaction) Add the cracking oil to a three-necked round-bottom flask, put in zeolite, stir and turn on the electric heating jacket. During the distillation reaction, first raise the temperature to 50°C and then increase the temperature by 3°C each time until obvious boiling occurs at about 170°C. During this period, heat slowly and wait for a while to prevent boiling. At about 210°C, the collection device begins to collect trace output. Continue heating, increase the temperature to 280°C, stop heating, and turn off the electric heating jacket. Collect the output to obtain the distilled light oil.

[0028] (3) Esterification reaction Pour the light oil into a three-necked flask, add methanol and KOH catalyst, and start the stirrer to stir; after stirring, turn on the water bath heating device, set the temperature to 63°C, the reaction time to 1.5h, and wait for the water bath to heat. The obtained product needs to be further poured into a split funnel to separate the methanol contained in the sample to obtain aviation biofuel (bio-aviation fuel). Among them, the mass ratio of alcohol to light oil is 20%:1; the mass ratio of the inorganic base KOH to light oil is 6%:1.

[0029] Example 2

[0030] The method is basically the same as that of Example 1, except that the mass ratio of inorganic base KOH to light oil is 5%:1.

[0031] Example 3

[0032] The method is basically the same as that of Example 1, except that the mass ratio of the inorganic base KOH to the light oil is 7%:1.

[0033] Comparative Example 1 The same preparation method as in Example 1 is used, except that an equal amount of NaOH is used to replace KOH in step (3).

[0034] Test method: Flash point of aviation biofuel (GB / T 21789-2008 Determination of flash point of petroleum products and other liquids - Abel closed cup method); Pour point of aviation biofuel (GB / T 3535 Pour point determination method for petroleum); Kinematic viscosity of aviation biofuel (GB / T 265-1988 Determination of kinematic viscosity of petroleum products and calculation of dynamic viscosity); The aviation biofuels of the above examples and comparative examples were tested, and the results obtained are shown in Table 1 below: Table 1

[0035] The above embodiments are merely examples for the purpose of clear explanation and are not intended to limit the implementation methods. It is clear to those skilled in the art that other different forms of changes or modifications may be made based on the above description. It is not necessary and impossible to list all the implementation methods here. The obvious changes derived from this Any modification or variation is still within the protection scope of the present invention.

Claims

1. A method for preparing aviation biofuel, characterized in that: The following steps are involved: (1) catalytic cracking of oleic acid to obtain cracking oil; (2) subjecting the pyrolysis oil to a distillation reaction to obtain a distilled light oil; (3) subjecting the light oil to an esterification reaction to obtain aviation biofuel.

2. The method for preparing aviation biofuel according to claim 1, characterized in that: Step (1), using oleic acid as a reactant, adding catalysts LGO (RM) and zeolite for catalytic cracking to obtain cracking oil.

3. The method for preparing aviation biofuel according to claim 2, characterized in that: Step (1), The mass ratio of the catalyst LGO (RM) to oleic acid is 2.8%-3%:1; The temperature of the pyrolysis oil collected from the catalytic cracking reaction is 390°C-430°C.

4. The method for preparing aviation biofuel according to claim 3, characterized in that: In step (1), during the catalytic cracking reaction, the temperature is first raised to 100°C-180°C by a temperature increase of 10°C each time; then the temperature is raised to 220°C by a temperature increase of 3°C each time; then the temperature is raised to 350°C by a temperature increase of 5°C each time; then the temperature is raised to 390°C-430°C, and the cracking oil is collected within the temperature range of 390°C-430°C.

5. The method for preparing aviation biofuel according to claim 1, characterized in that: Step (2), adding zeolite to the pyrolysis oil and performing a distillation reaction; the temperature of the light oil collected from the distillation reaction is 210° C.-280° C.

6. The method for preparing aviation biofuel according to claim 5, characterized in that: In step (2), during the distillation reaction, the temperature is first raised to 50°C, and then raised to 210°C-280°C by 3°C each time, and the light oil distilled is collected within the temperature range of 210°C-280°C.

7. The method for preparing aviation biofuel according to claim 1, characterized in that: Step (3), adding alcohol and inorganic base to the light oil to carry out esterification reaction, separating alcohol from the product after the esterification reaction, and obtaining the aviation biofuel.

8. The method for preparing aviation biofuel according to claim 7, characterized in that: Step (3), The alcohol is selected from methanol; The inorganic base is selected from KOH; The mass ratio of the alcohol to the light oil is 18%-22%:1; The mass ratio of the inorganic alkali to the light oil is 5%-7%:

1.

9. The method for preparing aviation biofuel according to claim 7, characterized in that: Step (3), The temperature of the esterification reaction is 60°C to 65°C; The esterification reaction time is 1-2h.

10. The method for preparing aviation biofuel according to claim 1, characterized in that: The aviation biofuel has a flash point of ≥38°C, a pour point of ≤-50°C, and a kinematic viscosity of ≥1.25 mm. 2 / s, acid value ≤1.7KOHmg / g.

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