Lead-free aviation gasoline composition and preparation method thereof

Abstract

The invention relates to the field of fuel oil, and discloses a lead-free aviation gasoline composition and a preparation method thereof. Relative to the total weight of the lead-free aviation gasoline composition, the composition contains 4 to 15 weight percent of C5 isoparaffin, 55 to 80 weight percent of C8 isoparaffin, 1 to 15 weight percent of ether compound and 1 to 20 weight percent of C8 and above aromatic hydrocarbon; wherein relative to the total weight of the composition, the weight content of C4 alkane is lower than 2wt%, and the weight content of C9 and above alkane is lower than 2wt%. The lead-free aviation gasoline composition does not contain uncommon components in gasoline pools, the types of the components are few, the lead-free aviation gasoline meeting the use requirements can be obtained under the condition that lead-containing substances, substances containing other metals and nitrogen-containing substances are not contained, and the lead-free aviation gasoline composition is easy to prepare and more environmentally friendly.

Description

Technical Field

[0001] The invention relates to the field of fuel oil, and in particular to an unleaded aviation gasoline composition and a preparation method thereof. Background Art

[0002] Aviation gasoline, also known as aviation piston engine fuel, is mainly used in aircraft equipped with reciprocating piston engines, such as armed helicopters, drones, primary trainer aircraft in the military field, and agricultural aircraft, meteorological aircraft, exploration aircraft, etc. in the general aviation field. The current standard is GB 1787-2018 "Aviation Piston Engine Fuel". The standard stipulates 5 types of aviation gasoline, of which No. 95 and No. 100 aviation gasoline are both leaded gasoline. With the emphasis on environmental protection and safety, it is an inevitable trend to use unleaded aviation gasoline to replace leaded aviation gasoline.

[0003] In addition, since the engine development process is long and will not be easily changed, the new fuel is required to adapt to the use requirements of the engine without causing major adjustments to the engine, which means that the new fuel should not contain components that have never been actually used or are uncommon. For example, CN106398783A proposed that 100 unleaded aviation gasoline contains aniline, N-methylaniline and m-toluidine, but these components do not exist in the traditional gasoline pool. Therefore, whether they have additional effects on the engine requires a lot of research work, and there is still a long way to go before practical application.

[0004] In the process of preparing unleaded aviation gasoline, economic efficiency also needs to be considered. The number of blending component types used and the use of pure chemicals should be reduced as much as possible. For example, CN 104673409 B proposes an unleaded, high-quality clean aviation gasoline, which has a motor octane number of more than 95 without the addition of lead. However, the blending components are relatively large and the proportion of pure chemicals is relatively high, resulting in high costs and is not suitable for production in refineries. Summary of the invention

[0005] The purpose of the present invention is to overcome the above-mentioned problems existing in the prior art and to provide an unleaded aviation gasoline composition and a preparation method thereof. The unleaded aviation gasoline composition does not contain components that are not common in the gasoline pool, has a small number of component types, and can obtain unleaded aviation gasoline that meets the use requirements without containing lead-containing substances, substances containing other metals, and nitrogen-containing substances. The unleaded aviation gasoline is more environmentally friendly and has a lower cost.

[0006] In order to achieve the above-mentioned object, the present invention provides an unleaded aviation gasoline composition on one hand, which contains 4-15wt% of C5 isoalkanes, 55-80wt% of C8 isoalkanes, 1-15wt% of ether compounds, and 1-20wt% of C8 and above aromatic hydrocarbons, relative to the total weight of the unleaded aviation gasoline composition;

[0007] Wherein, relative to the total weight of the composition, the weight content of C4 alkanes is less than 2wt%, and the weight content of C9 and above alkanes is less than 2wt%.

[0008] The second aspect of the present invention provides a method for preparing the unleaded aviation gasoline composition as described in the first aspect, the method comprising: first mixing various hydrocarbons and ether compounds.

[0009] The unleaded aviation gasoline composition provided by the present invention does not contain uncommon components in the gasoline pool, and has a small number of component types. It can obtain No. 95 unleaded aviation gasoline that meets the use requirements without containing lead-containing substances, substances containing other metals, and nitrogen-containing substances (such as aromatic amines), which is more environmentally friendly and has a lower cost. DETAILED DESCRIPTION

[0010] The endpoints and any values ​​of the ranges disclosed in this article are not limited to the precise ranges or values, and these ranges or values ​​should be understood to include values ​​close to these ranges or values. For numerical ranges, the endpoint values ​​of each range, the endpoint values ​​of each range and the individual point values, and the individual point values ​​can be combined with each other to obtain one or more new numerical ranges, which should be considered as specifically disclosed in this article.

[0011] In a first aspect, the present invention provides an unleaded aviation gasoline composition, which contains 4-15wt% of C5 isoalkanes, 55-80wt% of C8 isoalkanes, 1-15wt% of ether compounds, and 1-20wt% of C8 and above aromatic hydrocarbons, relative to the total weight of the unleaded aviation gasoline composition;

[0012] Wherein, relative to the total weight of the composition, the weight content of C4 alkanes is less than 2wt%, and the weight content of C9 and above alkanes is less than 2wt%.

[0013] It is understood that C8 and above aromatic hydrocarbons refer to aromatic hydrocarbons containing 8 or more carbon atoms, and C9 and above alkanes refer to alkanes containing 9 or more carbon atoms.

[0014] The inventors of the present invention have found in their research that by adopting the above scheme, it is possible to obtain No. 95 (meaning a motor octane number of not less than 95) unleaded aviation gasoline that meets the use requirements without containing lead-containing substances, substances containing other metals and nitrogen-containing substances, and using common components in the gasoline pool. The component types are relatively uncomplicated and more environmentally friendly.

[0015] According to the present invention, preferably, relative to the total weight of the composition, the weight content of C5 isoalkanes is 7-12 (for example, it can be 7, 7.1, 7.2, 7.3, 7.4, 7.5, 7.6, 7.7, 7.8, 7.9, 8, 8.1, 8.2, 8.5, 9, 9.5, 10, 10.5, 11, 11.5, 12 and the range formed by any two of the above values ​​and the values ​​within the range) wt%.

[0016] According to the present invention, preferably, relative to the total weight of the unleaded aviation gasoline composition, the weight content of C8 isoparaffins is 70-75 (for example, it can be 70, 70.3, 70.5, 70.8, 71, 71.3, 71.5, 71.8, 72, 72.5, 73, 73.5, 74, 74.5, 75 and the range formed by any two of the above values ​​and the value within the range) wt%.

[0017] According to the present invention, preferably, the weight content of the ether compound is 2-6 (for example, it can be 2, 2.5, 3, 3.5, 4, 4.5, 5, 5.5, 6 and the range formed by any two of the above values ​​and the value within the range) wt% relative to the total weight of the unleaded aviation gasoline composition.

[0018] According to the present invention, preferably, the ether compound is selected from C4-C8 ethers, more preferably methyl tert-butyl ether and / or ethyl tert-butyl ether.

[0019] According to the present invention, preferably, the weight content of aromatic hydrocarbons of C8 and above is 2-7 (for example, it can be 2, 2.5, 3, 3.5, 4, 4.5, 5, 5.5, 6, 6.5, 7 and the range formed by any two of the above values ​​and the value within the range) wt% relative to the total weight of the unleaded aviation gasoline composition.

[0020] According to the present invention, preferably, the weight content of C4 alkanes is 0.2-0.7 (for example, it can be 0.2, 0.25, 0.3, 0.35, 0.4, 0.45, 0.5, 0.55, 0.6, 0.65, 0.7 and the range formed by any two of the above values ​​and the value within the range) wt% relative to the total weight of the unleaded aviation gasoline composition.

[0021] According to the present invention, preferably, the weight content of C9 and above alkanes is 0.5-1.2 (for example, it can be 0.5, 0.6, 0.7, 0.8, 0.9, 1, 1.1, 1.2 and the range formed by any two of the above values ​​and the value within the range) wt% relative to the total weight of the unleaded aviation gasoline composition.

[0022] When the content of aviation gasoline is within the above range, the performance of aviation gasoline is better (it can meet the requirements of distillation range and other indicators while having a higher octane number).

[0023] According to the present invention, preferably, relative to the total weight of the unleaded aviation gasoline composition, the composition contains 65-92 (for example, 65, 68, 70, 72, 75, 78, 80, 82, 85, 86, 87, 88, 89, 90, 92 and ranges formed by any two of the above values ​​and values ​​within the range) wt%, more preferably 85-90 wt% of C5-C8 isoalkanes.

[0024] According to the present invention, preferably, relative to the total weight of the unleaded aviation gasoline composition, the weight content of C5-C6 isoalkanes in the composition is 7-18 (for example, it can be 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17 and the range formed by any two of the above values ​​and the value within the range) wt%, more preferably 12-15 wt%.

[0025] Under the circumstances described above, it can be ensured that aviation gasoline has better comprehensive performance.

[0026] According to the present invention, preferably, the aromatic hydrocarbons of C8 and above are selected from aromatic hydrocarbons of C8-C9, and more preferably are selected from at least one of xylene, ethylbenzene, isopropylbenzene and mesitylene. By adopting the scheme of the present invention, it is possible to obtain aviation gasoline with satisfactory performance without using toluene, which is more toxic.

[0027] Among them, the C4 alkane can be a normal and / or isomeric alkane of C4; the C5 isomeric alkane is isopentane; the types of C6-C8 isomeric alkanes and the proportions of each isomer are not particularly limited. Taking the C8 isomeric alkane as an example, it can be a mixture of various non-normal alkanes with 8 carbon atoms; the C9 and above alkanes can be isomeric alkanes of C9 and above, and the specific types and proportions of each isomer are not particularly limited.

[0028] According to the present invention, preferably, the composition further comprises an antioxidant, so that the oxidation of aviation gasoline can be delayed during use.

[0029] According to the present invention, preferably, the weight content of the antioxidant is 2-12 (for example, it can be 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12 and the range formed by any two of the above values ​​and the value within the range) mg / L relative to the total weight of the unleaded aviation gasoline composition. The amount of antioxidant added is very small, so it will not have a significant effect on the performance of the product. Generally, the performance of the composition can be measured before adding the antioxidant.

[0030] According to the present invention, preferably, the antioxidant is at least one selected from 2,6-di-tert-butyl-p-cresol, 2,4-dimethyl-6-tert-butylphenol and 2,6-di-tert-butylphenol, more preferably 2,6-di-tert-butyl-p-cresol.

[0031] According to the present invention, preferably, the composition does not contain toluene, nitrogen-containing compounds and metal compounds, which is more environmentally friendly and does not contain components that do not exist in traditional gasoline pools.

[0032] According to a particularly preferred embodiment of the present invention, the aviation gasoline composition contains only the components mentioned above.

[0033] In a second aspect, the present invention provides a method for preparing the unleaded aviation gasoline composition of the first aspect, the method comprising: first mixing the hydrocarbons and ether compounds. Mix the hydrocarbons and ether compounds mentioned in the first aspect.

[0034] According to the present invention, preferably, the method further comprises: mixing the first mixture obtained by the first mixing with an antioxidant, wherein the specific type of the antioxidant and the content of the antioxidant after mixing are as described in the first aspect.

[0035] Among them, the above-mentioned hydrocarbons can be derived from relatively pure chemicals or from mixtures containing the above-mentioned hydrocarbons produced in the field of petroleum refining, such as alkylated gasoline from a petroleum refinery. The present invention has no particular limitation on this, as long as aviation gasoline that meets the above composition can be obtained. According to a particularly preferred embodiment of the present invention, at least part of the C4-C8 alkanes is provided by alkylated gasoline from a petroleum refinery. Generally, the alkylated gasoline contains the C4-C8 alkanes as described in the first aspect. When providing the C5-C8 isoalkanes as described in the first aspect, the alkylated gasoline may also contain a very small amount of normal alkanes or a smaller amount of olefins, but the amount of both is very small relative to the isoalkanes, which can be almost ignored, and the use of alkylated gasoline from a petroleum refinery will not significantly introduce impurities. When using alkylated gasoline, other components, such as isooctane (which can be provided by industrial isooctane), can be added at the same time to meet the content requirements in the first aspect.

[0036] According to a particularly preferred embodiment of the present invention, relative to the total weight of the unleaded aviation gasoline composition, the weight content of C4 alkanes is 0.35-0.4wt%, the weight content of C5 isoalkanes is 7.2-8.1wt%, the weight content of C6 isoalkanes is 5.5-6.4wt%, the weight content of C7 isoalkanes is 2.8-3.4wt%, the weight content of C8 isoalkanes is 70-73wt%, the weight content of C9 and above alkanes is 0.8-1.2wt%, the weight content of C8 and above aromatics is 4-6wt%, and the weight content of methyl tert-butyl ether is 4-6wt%.

[0037] The present invention is described in detail below.

[0038] Recipe 1-18

[0039] Alkylated gasoline, industrial isooctane, methyl tert-butyl ether (MTBE), and C8-C9 aromatics are mixed to prepare aviation gasoline compositions whose component contents meet the conditions in Table 1. Among them, butane includes normal butane and isobutane. Isoalkanes of C9 and above include isoalkanes of C9-C12.

[0040] Table 1

[0041]

[0042] Test Example 1

[0043] For a new aviation gasoline, the key physical and chemical properties to be examined are motor octane number, distillation range and calorific value related properties. Other properties are usually easy to meet the index requirements, especially when using common components in the gasoline pool. For the aviation gasoline compositions of the above formulas, the relevant properties were measured according to the corresponding methods specified in GB 1787-2018 and compared with the index requirements of No. 95 aviation gasoline. The results are shown in Table 2.

[0044] Table 2

[0045]

[0046] Among them, formulas 1, 8-10, 12-13, and 16-17 are not within the scope of claim 1 of the present invention. It can be seen that the solutions that are not within the scope of claim 1 of the present invention have at least one property that cannot meet the use requirements.

[0047] It can be seen from the above results that the formulations 2-7, 11, and 14-15 of the solution provided by the present invention do not contain uncommon components in the gasoline pool, and have fewer types of components. In addition, it is possible to obtain No. 95 unleaded aviation gasoline that meets the use requirements without containing lead-containing substances, substances containing other metals, and nitrogen-containing substances (such as aromatic amines). In particular, the overall performance of the aviation gasoline using the formulations 4, 6, and 14-15 of the more preferred solution of the present invention is better.

[0048] Test Example 2

[0049] The antioxidant 2,6-di-tert-butyl-p-methylphenol was added to the aviation gasoline compositions prepared from Formula 6, Formula 14, and Formula 15, and mixed evenly, so that the content of 2,6-di-tert-butyl-p-methylphenol in the final aviation gasoline composition was about 10 mg / L. Since the amount of the antioxidant was very small, it can be considered that the content of each component in the final aviation gasoline composition is no different from that in Table 1.

[0050] The other properties analysis of GB 1787-2018 was carried out on the aviation gasoline compositions after adding antioxidants. All the results are shown in Table 3.

[0051] Table 3

[0052]

[0053]

[0054] It can be seen from the above results that the scheme provided by the present invention can obtain No. 95 unleaded aviation gasoline that meets the index requirements without containing uncommon components in the gasoline pool, with a small number of component types, and without lead-containing substances, substances containing other metals, and nitrogen-containing substances (such as aromatic amines). It is more environmentally friendly and has a lower cost.

[0055] The preferred embodiments of the present invention are described in detail above, but the present invention is not limited thereto. Within the technical concept of the present invention, the technical solution of the present invention can be subjected to a variety of simple modifications, including the combination of various technical features in any other suitable manner, and these simple modifications and combinations should also be regarded as the contents disclosed by the present invention and belong to the protection scope of the present invention.

Claims

1. An unleaded aviation gasoline composition, characterized in that: Relative to the total weight of the unleaded aviation gasoline composition, the composition contains 4-15wt% of C5 isoalkanes, 55-80wt% of C8 isoalkanes, 1-15wt% of ether compounds, and 1-20wt% of C8 and above aromatics; Wherein, relative to the total weight of the composition, the weight content of C4 alkanes is less than 2wt%, and the weight content of C9 and above alkanes is less than 2wt%.

2. The unleaded aviation gasoline composition according to claim 1, wherein: The weight content of C5 isoparaffins is 7-12 wt % relative to the total weight of the composition.

3. The unleaded aviation gasoline composition according to claim 1, wherein: Relative to the total weight of the unleaded aviation gasoline composition, the weight content of C8 isoparaffins is 70-75wt%.

4. The unleaded aviation gasoline composition according to claim 1 or 2, wherein: The weight content of the ether compound is 2-6wt% relative to the total weight of the unleaded aviation gasoline composition; And / or, the ether compound is selected from C4-C8 ethers, preferably methyl tert-butyl ether and / or ethyl tert-butyl ether.

5. The unleaded aviation gasoline composition according to claim 1 or 2, wherein: Relative to the total weight of the unleaded aviation gasoline composition, the weight content of aromatic hydrocarbons of C8 and above is 2-7wt%.

6. The unleaded aviation gasoline composition according to claim 1 or 3, wherein: Relative to the total weight of the unleaded aviation gasoline composition, the weight content of C4 alkanes is 0.2-0.7wt%.

7. The unleaded aviation gasoline composition according to claim 1 or 3, wherein: Relative to the total weight of the unleaded aviation gasoline composition, the weight content of C9 and above alkanes is 0.5-1.2wt%.

8. The unleaded aviation gasoline composition according to claim 1 or 2, wherein: Relative to the total weight of the unleaded aviation gasoline composition, the composition contains 65-92 wt%, preferably 85-90 wt% of C5-C8 isoparaffins; And / or, relative to the total weight of the unleaded aviation gasoline composition, the weight content of C5-C6 isoalkanes in the composition is 7-18wt%, preferably 12-15wt%.

9. The unleaded aviation gasoline composition according to claim 1 or 2, wherein: The aromatic hydrocarbons of C8 and above are selected from aromatic hydrocarbons of C8-C9, and more preferably are selected from at least one of xylene, ethylbenzene, isopropylbenzene and mesitylene.

10. The unleaded aviation gasoline composition according to claim 1 or 2, wherein: The composition also includes an antioxidant.

11. The unleaded aviation gasoline composition according to claim 10, wherein: The weight content of the antioxidant is 2-12 mg / L relative to the total weight of the unleaded aviation gasoline composition; And / or, the antioxidant is at least one selected from 2,6-di-tert-butyl-p-cresol, 2,4-dimethyl-6-tert-butylphenol and 2,6-di-tert-butylphenol, preferably 2,6-di-tert-butyl-p-cresol.

12. The unleaded aviation gasoline composition according to claim 1 or 2, wherein: The composition does not contain toluene, nitrogen-containing compounds and metal compounds.

13. A method for preparing the unleaded aviation gasoline composition according to any one of claims 1 to 12, characterized in that: The method comprises: first mixing various hydrocarbons and ether compounds.

14. The method according to claim 13, wherein: The method further includes: mixing the first mixture obtained by the first mixing with an antioxidant.

15. The method according to claim 13 or 14, wherein: At least part of the C4-C8 alkanes are provided by alkylation gasoline in a petroleum refinery.

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