Standard oil for testing spark-ignition engine in high and cold environment and preparation method of standard oil
By using a standard fuel with specific components for high-altitude, cold-weather ignition engine testing, the problem of insufficient fuel volatility in extremely cold environments has been solved, enabling rapid ignition and stable combustion of the engine, and ensuring the reliability and stability of the test data.
Patent Information
- Application Number
- CN202511054327.1
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2025-07-30
- Publication Date
- 2025-11-11
AI Technical Summary
The volatility of existing fuels decreases sharply in cold environments, leading to delayed cold starts, idling vibrations, and even start-up failures, which affects the authenticity and stability of test data.
The test standard oil for high-altitude cold-weather spark-ignition engines uses a specific combination of components, including high-boiling-point aromatic solvent SA1500, alkylated oil, heavy naphtha, etc., and the vapor pressure is increased to above 80 kPa through precise combination to ensure rapid ignition and stable combustion of fuel in extremely cold environments.
It enables rapid ignition and stable combustion of the engine in extremely cold environments, provides reliable fuel supply, and helps optimize engine performance and achieve technological breakthroughs.
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Abstract
Description
Technical Field
[0001] This invention relates to the field of fuel technology, specifically to a standard oil for testing spark-ignition engines in extremely cold environments and its preparation method. Background Technology
[0002] Against the backdrop of accelerated technological iteration in the global automotive industry, engine performance testing is expanding into extreme environments. High-altitude cold-weather testing, as a crucial step in verifying the low-temperature adaptability of powertrain systems, has become a rigorous and mandatory test for engine manufacturers. When ambient temperatures plummet to below -40°C, conventional fuels experience a sharp decline in volatility, failing to quickly form a combustible mixture sufficient for ignition. This leads to delayed cold starts, idling vibrations, and even start-up failures. This severely interferes with the accuracy and stability of test data, making it difficult for manufacturers to obtain precise performance parameters of the engine under extreme operating conditions.
[0003] To overcome the aforementioned technical bottlenecks and eliminate the interference of fuel performance on test results, a high vapor pressure fuel specifically designed for high-altitude and cold-weather testing scenarios is urgently needed. This fuel needs to significantly enhance its low-temperature volatility by increasing its vapor pressure to above 80 kPa, ensuring rapid ignition and stable combustion of the engine in extremely cold environments. This will provide a reliable fuel guarantee for high-altitude and cold-weather testing, contributing to engine performance optimization and technological breakthroughs. Summary of the Invention
[0004] To address the problems of existing spark-ignition engine evaporative emission testing oils being unsuitable for high-altitude and cold-weather testing, exhibiting unstable quality, and showing significant differences in volatility, boiling point, and vapor pressure between different batches, this invention provides a standard oil for high-altitude and cold-weather spark-ignition engine testing and its preparation method. Its main components include high-boiling-point aromatic solvent SA1500, high-boiling-point aromatic solvent SA1000, alkylated oil, heavy naphtha, toluene, xylene, 1-octene, isopentenene, and isopentane. This standard oil, with its high vapor pressure and highly stable properties, significantly enhances the low-temperature volatility of fuel, ensuring rapid ignition and stable combustion in extremely cold environments. This provides reliable fuel for high-altitude and cold-weather testing, contributing to engine performance optimization and technological breakthroughs.
[0005] To address the above problems, this invention provides a standard oil for testing spark-ignition engines in extremely cold environments, which, by volume fraction, consists of the following components: 27-29 parts alkylated oil; 35-37 parts isopentane; 5-6 parts isopentenene; 5-6 parts of 1-octene; 3-4 parts of heavy naphtha; 4-6 parts toluene; 4-6 parts xylene; 5-7 parts of high-boiling-point aromatic solvent SA1000; 5-6 parts of high-boiling-point aromatic solvent SA1500.
[0006] Furthermore, the alkylated oil is a fuel oil rich in isooctane produced by the reaction of isobutane and isobutene, with an isooctane content (volume fraction) >65%, an octane number of 95~97, a distillation range of 30℃~190℃, a vapor pressure of 63~65kPa, an aromatic content (volume fraction) <0.1%, an olefin content (volume fraction) <0.1%, a 10% evaporation temperature <60℃, a 90℃ distillation volume >25%, a 50% evaporation temperature of 105~110℃, a 90% evaporation temperature of 120~130℃, and a final boiling point <190℃.
[0007] The method for reacting isobutylene and isobutane to generate alkylated oil is an existing technology. For example, you can refer to the literature (Zhao Yang, Jiao Dayong, Yang Zhongyi. Analysis of factors affecting the octane number of alkylated oil produced by sulfuric acid method and optimization strategy. Petrochemical Technology and Economy. 2025, 41(2):28-32). As long as the alkylated oil can meet the above requirements, no special limitation is required.
[0008] Furthermore, the isopentane has a purity >97.0%, an octane number ≥94, and a vapor pressure of 139~141 kPa; the isopentene has a purity >99.0%, an RON of 96.5~97, a vapor pressure of 95.5~96.5 kPa, and an olefin content (volume fraction) >99.0%.
[0009] Isopentane and isopentenene are key raw materials for producing standard test oils for spark-ignition engines in cold environments due to their high vapor pressure. However, their distillation range is too low, and excessive amounts of isopentenane and isopentenene can lead to 50% of the evaporation temperature of the standard test oils for spark-ignition engines in cold environments being too low. Therefore, the above-mentioned addition amount must be controlled.
[0010] 1-Octene can supplement the olefin content required for the standard fuel for spark-ignition engines in cold environments, while its high boiling point prevents its 50% evaporation temperature from being too low; Toluene, high-boiling-point aromatic solvent SA1000, and high-boiling-point aromatic solvent SA1500 can supplement the aromatic content required for the standard fuel for spark-ignition engines in cold environments. Among them, the high-boiling-point aromatic solvents SA1000 and SA1500, with their high boiling point characteristics, ensure a high 90% evaporation temperature, thus ensuring the fuel economy performance of the standard fuel for spark-ignition engines in cold environments; Heavy naphtha, with its high distillation range, prevents the 50% evaporation temperature of the standard fuel for spark-ignition engines in cold environments from being too low.
[0011] To meet the requirements of high vapor pressure, 50% evaporation temperature, 90% evaporation temperature, aromatic hydrocarbon and olefin content for the test standard oil of spark-ignition engines in high-altitude and cold-weather environments, the components need to be precisely combined to achieve stable quality indicators, excellent cold start performance (rapid ignition) and stable combustion of the test standard oil for spark-ignition engines in high-altitude and cold-weather environments.
[0012] The 1-octene has a purity >99.0%, RON 28~29, vapor pressure 5kPa, and olefin content (volume fraction) >99.0%.
[0013] The toluene has a purity >98.0% and a RON of 118~120; the xylene has a purity >98.0% and a RON of 117~118.
[0014] Furthermore, the heavy naphtha is a product extracted from the middle section of a crude oil distillation tower during petroleum processing, with a distillation range of 90℃~165℃, an octane number of 66.5~67, a vapor pressure of 13~14kPa, an aromatic content (volume fraction) of 14%~16%, and an olefin content (volume fraction) of <1%.
[0015] Furthermore, the high-boiling-point aromatic solvent SA1000 has a boiling range of 160℃~180℃, an octane number ≥117, and an aromatic content (volume fraction) >99.0%.
[0016] The high-boiling-point aromatic solvent SA1000 is a commercially available product. After obtaining SA1000, the hydrocarbon composition is tested (which can be done by high performance gas chromatography or other available methods). It can be used if the xylene:trimethylbenzene:tetramethylbenzene volume ratio is 0.6~1:8.0~8.6:0.8~1.
[0017] Furthermore, the high-boiling-point aromatic solvent SA1500 has a boiling range of 185℃~205℃, an octane number ≥117, and an aromatic content (volume fraction) >99.0%.
[0018] The high-boiling-point aromatic solvent SA1500 is a commercially available product. After obtaining SA1500, hydrocarbon composition testing is performed (which can be done by high-performance gas chromatography or other available methods). It can be used if the requirement of trimethylbenzene:tetramethylbenzene volume ratio of 0.3~0.5:1~1.2 is met.
[0019] High-boiling-point aromatic solvents SA1000 and SA1500, with their high aromatic content and high distillation range, are better able to meet the requirements of 90% evaporation temperature of 150~165℃ for spark-ignition engine test standard oils in cold environments.
[0020] Furthermore, the aforementioned standard oil for testing spark-ignition engines in cold environments has an octane number of 95-98, a vapor pressure of 80-85 kPa, an aromatic content (volume fraction) of 20%-25%, an olefin content (volume fraction) of 10%-15%, an evaporation temperature of <70℃ for 10% evaporation, an evaporation temperature of 90-95℃ for 50% evaporation, an evaporation temperature of 150-165℃ for 90% evaporation, and a final boiling point of <205℃.
[0021] This invention further provides a method for preparing the standard oil for testing spark-ignition engines in extremely cold environments, comprising the following steps: According to the distillation range from heavy to light, the high-boiling-point aromatic solvent SA1500, high-boiling-point aromatic solvent SA1000, alkylated oil, heavy naphtha, toluene, xylene, 1-octene, isopentenene, and isopentane from each raw material oil tank are introduced into the finished oil blending tank in a certain proportion. Then, the circulation pump of the finished oil blending tank is turned on and mixed and circulated for 1-2 hours. After sampling and testing to ensure that the requirements are met, the standard oil for high-altitude cold environment spark-ignition engine testing is obtained.
[0022] The present invention has achieved the following beneficial effects: This invention utilizes specific components in specific amounts to obtain a standard oil for testing spark-ignition engines in extremely cold environments, exhibiting stable performance across various parameters. This standard oil, with its high vapor pressure and highly stable properties, significantly enhances the low-temperature volatility of fuel, ensuring rapid ignition and stable combustion in extremely cold environments. This provides reliable fuel for cold-weather testing, contributing to engine performance optimization and technological breakthroughs.
[0023] Furthermore, the compounding method provided by this invention is simple in process and mild in conditions, making it suitable for large-scale industrial production. Detailed Implementation
[0024] The technical solution of the present invention will be further described below with reference to specific embodiments. These embodiments are only used to illustrate the technical solution of the present invention in more detail and should not be construed as limiting the scope of protection of the present invention.
[0025] In the various embodiments of this application, all components involved are products of oil refining processes and chemical products, which are commercially available and there is no restriction on the manufacturers.
[0026] This invention provides a standard test oil for spark-ignition engines in high-altitude and cold-weather environments. It is composed of high-boiling-point aromatic solvent SA1500, high-boiling-point aromatic solvent SA1000, alkylated oil, heavy naphtha, toluene, xylene, 1-octene, isopentenene, and isopentane. The test oil meets the following specifications: octane number 95~98, vapor pressure 80~85kPa, aromatic content (volume fraction) 20%~25%, olefin content (volume fraction) 10%~15%, evaporation temperature <70℃ for 10%, evaporation temperature 90~95℃ for 50%, evaporation temperature 150~165℃ for 90%, and final boiling point <205℃.
[0027] Specifically, the standard oil for testing spark-ignition engines in extremely cold environments, by volume fraction, consists of the following components: 27 to 29 parts of alkylated oil; 35 to 37 parts isopentane; 5 to 6 parts isopentenene; 5 to 6 parts of 1-octene; 3 to 4 parts of heavy naphtha; 4 to 6 parts toluene; 4 to 6 parts xylene; 5 to 7 parts of high-boiling-point aromatic solvent SA1000; 5 to 6 parts of high-boiling-point aromatic solvent SA1500.
[0028] The alkylated oil has an isooctane content (volume fraction) of 68%, an octane number of 96.8, a distillation range of 33℃ to 186℃, a vapor pressure of 63.1 kPa, an aromatic content (volume fraction) of 0, an olefin content (volume fraction) of 0, a 10% evaporation temperature of 58.2℃, a 90℃ distillation volume of 26%, a 50% evaporation temperature of 106℃, a 90% evaporation temperature of 122℃, and a final boiling point of 186℃.
[0029] The method for reacting isobutylene and isobutane to generate alkylated oil is an existing technology. For example, you can refer to the literature (Zhao Yang, Jiao Dayong, Yang Zhongyi. Analysis of factors affecting the octane number of alkylated oil produced by sulfuric acid method and optimization strategy. Petrochemical Technology and Economy. 2025, 41(2):28-32). As long as the alkylated oil can meet the above requirements, no special limitation is required.
[0030] The purity of isopentane is 99.0%, the octane number is 94, and the vapor pressure is 140 kPa; the purity of isopentene is 99.5%, the RON is 96.7, the vapor pressure is 95.9 kPa, and the olefin content (volume fraction) is 99.2%.
[0031] The purity of 1-octene is 99.5%, the RON is 28.7, the vapor pressure is 5 kPa, and the olefin content (volume fraction) is 99.5%.
[0032] Toluene has a purity of 99.0% and a RON of 119.5; xylene has a purity of 99.0% and a RON of 118.
[0033] Heavy naphtha has a distillation range of 90℃~165℃, an octane number of 66.8, a vapor pressure of 13.9 kPa, an aromatic content (volume fraction) of 15%, and an olefin content (volume fraction) of 0.9%.
[0034] The high-boiling-point aromatic solvent SA1000 has a boiling range of 160℃~178℃, an octane number of 117, and an aromatic content (volume fraction) of 99.2%.
[0035] The high-boiling-point aromatic solvent SA1000 is a commercially available product. After obtaining SA1000, the hydrocarbon composition is tested (by high-performance gas chromatography or other available methods). It can be used if the xylene:trimethylbenzene:tetramethylbenzene volume ratio is 0.6~1:8.0~8.6:0.8~1.
[0036] The high-boiling-point aromatic solvent SA1500 has a boiling range of 185℃~201℃, an octane number of 117, and an aromatic content (volume fraction) of 99.2%.
[0037] The high-boiling-point aromatic solvent SA1500 is a commercially available product. After obtaining SA1500, hydrocarbon composition testing can be performed (which can be done by high-performance gas chromatography or other available methods). It can be used if the requirement of trimethylbenzene:tetramethylbenzene volume ratio of 0.3~0.5:1~1.2 is met.
[0038] This invention also provides the standard oil for testing spark-ignition engines in cold environments as described in the above technical solution. It is prepared using an oil blending device, and its component ratios and blending scheme are shown in Table 1. All ratios shown in Table 1 are volume ratios, and the preparation methods are the same, involving the following steps: According to the distillation range from heavy to light, the high-boiling-point aromatic solvent SA1500, high-boiling-point aromatic solvent SA1000, alkylated oil, heavy naphtha, toluene, xylene, 1-octene, isopentenene, and isopentane from the raw material tanks are introduced into the finished oil blending tank in the following proportions. Then, the circulation pump of the oil blending tank is turned on and mixed and circulated for 2 hours. Samples are taken for testing to obtain the standard oil for high-altitude cold-weather spark-ignition engines. The octane number is tested according to GB / T 5487, the vapor pressure is tested according to GB / T 8017, the aromatic content (volume fraction) is tested according to GB / T 30519, the olefin content (volume fraction) is tested according to NB / SH / T 0663, and the 10% evaporation temperature, 50% evaporation temperature, 90% evaporation temperature, and final boiling point are tested according to GB / T 6536.
[0039] This invention provides a standard oil for testing spark-ignition engines in extremely cold environments. The raw materials are readily available and do not contain any special ingredients. This standard oil, with its high vapor pressure and highly stable properties, significantly enhances the low-temperature volatility of fuel, ensuring rapid ignition and stable combustion in extremely cold environments. It provides reliable fuel for cold-weather testing, contributing to engine performance optimization and technological breakthroughs.
[0040] Furthermore, the compounding method provided by this invention is simple in process and mild in conditions, making it suitable for large-scale industrial production.
[0041] To further illustrate the technical solution of the present invention, the following embodiments will be described in detail.
[0042] The compounding schemes (by volume ratio) of the embodiments and comparative examples are shown in Table 1: Table 1. Compound formulations of Examples 1-3 and Comparative Examples 1-3 Examples 1-3 and Comparative Examples 1-3 differ only in their components; the preparation methods are the same, and the steps described above are followed.
[0043] The test oils of the above embodiments and comparative examples have the following index results: Table 2: Table 2. Index results of Examples 1-3 and Comparative Examples 1-3 As shown in Table 2, the test oils provided in Examples 1-3 meet the required specifications, namely, octane number 95-98, vapor pressure 80-85 kPa, aromatic content (volume fraction) 20%-25%, olefin content (volume fraction) 10%-15%, 10% evaporation temperature <70℃, 50% evaporation temperature 90-95℃, 90% evaporation temperature 150-165℃, and final boiling point <205℃. However, the specifications of Comparative Examples 1-3 do not meet the requirements for high-altitude cold-weather spark-ignition engine test standard oils used for high-altitude cold-weather performance testing, namely, octane number 95-98, vapor pressure 80-85 kPa, aromatic content (volume fraction) 20%-25%, olefin content (volume fraction) 10%-15%, 10% evaporation temperature <70℃, 50% evaporation temperature 90-95℃, 90% evaporation temperature 150-165℃, and final boiling point <205℃.
[0044] Low-temperature cold start test: The prepared engine of the China VIB 2.0T test vehicle was placed in an environmental test chamber at a temperature below -40°C, and the engine and all vehicle electrical equipment were turned off. The engine was allowed to stand in the environmental test chamber for more than 8 hours to ensure that the engine oil, coolant, and the temperature of all vehicle components were consistent with the ambient temperature.
[0045] Start the engine, and the starter motor will drive the engine. Record the time from when the starter motor starts working until the engine can run stably on its own (engine speed stabilizes at 500 r / min and voltage rises, starting current decreases to almost zero). This time is the engine cold start time. The test results are as follows: Table 3. Results of engine cold start test in high-altitude and cold environments In examples 1-3, the startup time was about 6 seconds in extremely cold environments below -40℃, and the startup time was relatively stable; while in comparison examples 1-3, the startup time was significantly longer and the time deviation was larger.
[0046] Fuel consumption test: The test used a China VI B emission standard 2.0T gasoline engine, placed in an environmental test chamber below -40°C, and conducted a WLTC transient cycle test on a bench dynamometer. The fuel consumption of the test example was measured. The test results are as follows: Table 4. Fuel consumption test results in high-altitude and cold environments The fuel consumption of Examples 1-3 was lower than that of Comparative Examples 1-3, and the fuel consumption deviation of Examples 1-3 was within 0.1%.
[0047] The above description is merely a preferred embodiment of the present invention and is not intended to limit the present invention. Any equivalent substitutions or modifications made by those skilled in the art within the spirit and principle of the present invention without any creative effort should be included within the protection scope of the present invention.
Claims
1. A standard oil for testing spark-ignition engines in extremely cold environments, characterized in that: It consists of the following components by volume: 27-29 parts alkylated oil; 35-37 parts isopentane; 5-6 parts isopentenene; 5-6 parts of 1-octene; 3-4 parts of heavy naphtha; 4-6 parts toluene; 4-6 parts xylene; 5-7 parts of high-boiling-point aromatic solvent SA1000; 5-6 parts of high-boiling-point aromatic solvent SA1500.
2. The standard oil for testing spark-ignition engines in cold environments according to claim 1, characterized in that: The aforementioned standard oil for testing spark-ignition engines in cold environments has an octane rating of 95-98, a vapor pressure of 80-85 kPa, an aromatic content of 20%-25% by volume, an olefin content of 10%-15% by volume, an evaporation temperature of <70℃ for 10% evaporation, an evaporation temperature of 90-95℃ for 50% evaporation, an evaporation temperature of 150-165℃ for 90% evaporation, and a final boiling point of <205℃.
3. The standard oil for testing spark-ignition engines in extremely cold environments according to claim 1, characterized in that: The alkylated oil is a fuel oil rich in isooctane produced by the reaction of isobutane and isobutene. The volume fraction of isooctane content is >65%, the octane number is 95~97, the distillation range is 30℃~190℃, the vapor pressure is 63~65kPa, the volume fraction of aromatics content is <0.1%, the volume fraction of olefins content is <0.1%, the 10% evaporation temperature is <60℃, the 90℃ distillation volume is >25%, the 50% evaporation temperature is 105~110℃, the 90% evaporation temperature is 120~130℃, and the final boiling point is <190℃.
4. The standard oil for testing spark-ignition engines in high-altitude cold environments according to claim 1, characterized in that: The isopentane has a purity >97.0%, an octane number ≥94, and a vapor pressure of 139~141 kPa; the isopentene has a purity >99.0%, an RON of 96.5~97, a vapor pressure of 95.5~96.5 kPa, and an olefin content volume fraction >99.0%.
5. The standard oil for testing spark-ignition engines in extremely cold environments according to claim 1, characterized in that: The 1-octene has a purity >99.0%, RON 28~29, vapor pressure 5 kPa, and olefin content volume fraction >99.0%.
6. The standard oil for testing spark-ignition engines in extremely cold environments according to claim 1, characterized in that: The toluene has a purity >98.0% and a RON of 118~120; the xylene has a purity >98.0% and a RON of 117~118.
7. The standard oil for testing spark-ignition engines in extremely cold environments according to claim 1, characterized in that: The heavy naphtha has a distillation range of 90℃~165℃, an octane number of 66.5~67, a vapor pressure of 13~14kPa, an aromatic content of 14%~16% by volume, and an olefin content of <1% by volume.
8. The standard oil for testing spark-ignition engines in extremely cold environments according to claim 1, characterized in that: The high-boiling-point aromatic solvent SA1000 has a boiling range of 160℃~180℃, an octane number ≥117, and an aromatic content volume fraction >99.0%. The xylene:trimethylbenzene:tetramethylbenzene volume ratio in the high-boiling-point aromatic solvent SA1000 is 0.6~1:8.0~8.6:0.8~1. The high-boiling-point aromatic solvent SA1500 has a boiling range of 185℃~205℃, an octane number ≥117, and an aromatic content volume fraction >99.0%. The volume ratio of trimethylbenzene to tetramethylbenzene in the high-boiling-point aromatic solvent SA1500 is 0.3~0.5:1~1.
2.
9. A method for preparing the standard oil for high-altitude cold-weather spark-ignition engines according to any one of claims 1-8, comprising the following steps: High-boiling-point aromatic solvent SA1500, high-boiling-point aromatic solvent SA1000, alkylated oil, heavy naphtha, toluene, xylene, 1-octene, isopentenene, and isopentane are sequentially introduced into the finished oil compounding tank in proportion. Then, the circulation pump of the finished oil compounding tank is turned on and mixed and circulated for 1-2 hours. After sampling and testing to ensure that the requirements are met, the standard oil for high-altitude cold-weather spark-ignition engines is obtained.