【Basic Knowledge Activity】Professional “Basic Knowledge” in the petrochemical industry: What is the method used to indicate the anti-knock properties of automotive gasoline?
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This post was last edited by Adventure Wang on 2016-3-6 at 17:15. What is the method used to indicate the anti-knock property of automotive gasoline? The anti-knock property of automotive gasoline is expressed using the octane rating. There are mainly two methods for determining the octane number of motor gasoline: the Motor Method (MON) and the Research Method (RON). ============================================= [Petrochemical Section] We are now compiling posts related to “basic knowledge”. (The forum is offering surprises and great prizes for participants!) http://bbs.hcbbs.com/thread-1557057-1-1.html (Source: Haichuan Chemical Forum) We encourage various regions to organize or individuals to independently post content related to basic knowledge. The content can be compiled from online sources or created originally; multiple topics can be covered. There are no restrictions on how to participate – it could be an explanation of a single term or a series of explanations regarding certain principles. What are some suggestions and methods for getting in touch with cleaners? The regular administrator will reward the content that performs well. You will also be rewarded for regions where the activities are more active. (Regions should also conduct summarization and optimization based on the amount of such content available in their area.) ———————————————— The second phase of the event runs from February 20, 2016, to the end of June 2016; at least 50 award vouchers are available for you to claim (mugs, power banks, USB drives, and other prizes or event benefits). Awards can be given at any time based on performance, and additional rewards can also be granted at any time depending on performance. (12,000 event points and rewards await the regions that perform well)
The anti-knock properties of motor gasoline are expressed by the octane number. There are mainly two methods for determining the octane rating of automotive gasoline: the Motor Method (MON) and the Research Method (RON)
The anti-knock property of gasoline refers to its ability to resist knock combustion under various operating conditions. The anti-knock property of automotive gasoline is expressed by the octane rating. The higher the octane number, the better the anti-knock properties. The anti-knock capacity of gasoline is related to its chemical composition. Alkanes with branches, as well as alkenes and aromatics, generally possess excellent anti-knock properties. It is specified that octane number of isooctane is 100, with good anti-knock properties ； Heptane has an octane rating of 0 and poor anti-knock properties. The octane number of gasoline is determined by an octane tester. High-octane gasoline can meet the needs of gasoline engines with high compression ratios. A gasoline engine with a high compression ratio has higher thermal efficiency, which allows for fuel savings. Increasing the octane number of gasoline is mainly achieved by adding high-octane gasoline components; it can also be accomplished by adding anti-knock agents such as MTBE. Gasoline grades are classified according to their octane number. The octane number of gasoline is a measure of its anti-knock properties under lean mixture conditions; numerically, it equals the volume percentage of isooctane contained in a standard fuel that exhibits the same anti-knock properties as the sample under specified conditions.
The knock resistance of gasoline refers to its ability to operate without knocking in an engine with a certain compression ratio. The anti-knock properties of motor gasoline are indicated by its octane number; the higher the octane number, the better the anti-knock performance
The anti-knock property of gasoline refers to its ability to resist knock combustion under various operating conditions. The anti-knock property of automotive gasoline is expressed by the octane rating. The higher the octane rating, the better the anti-knock property.
What is the method used to indicate the anti-knock property of automotive gasoline? Octane rating
The knock resistance of gasoline refers to its ability to operate without knocking in an engine with a certain compression ratio. The anti-knock property of automotive gasoline is expressed by the octane rating; the higher the octane rating, the better the anti-knock property. There are two methods for determining octane rating: the motor method and the research method. The Motor Octane Number (MON) reflects the anti-knock properties of gasoline under heavy loads and high engine speeds, while the Research Octane Number (RON) indicates its anti-knock properties at low engine speeds
The indicators used to evaluate the anti-knock performance of gasoline are octane number and anti-knock index. Octane rating is one of the most important quality indicators for automotive gasoline; it represents a **comprehensive reflection of the level of the refining industry as well as the technology used in vehicle design and manufacturing. The octane number refers to the volume percentage of isooctane in a standard fuel with the same anti-knock properties as gasoline. Octane number is measured in a standard single-cylinder engine, under strict specified conditions, by comparing it with a certain standard fuel. The standard fuels for measuring octane number are isooctane (2,2,4-trimethylpentane) and n-heptane; isooctane, which has extremely high anti-knock properties, is assigned an octane number of 100, while n-heptane, which has very poor anti-knock properties, has an octane number of 0. By mixing the two standard fuels in different volume ratios, a standard fuel with an octane rating of 0 to 100 units is obtained, with the octane rating of this standard fuel expressed as a volume percentage of isooctane content. When determining the octane rating of gasoline, the gasoline to be tested is compared with a selected standard fuel under strictly specified conditions in an octane rating apparatus; when their resistance to detonation is exactly equal, the octane rating of the standard fuel (i.e., the volume percentage of isooctane) is taken as the octane rating of the fuel being tested. For example, if the octane rating of a certain gasoline is 90, it means that its anti-knock properties are the same as those of a standard fuel composed of 90% isooctane and 10% n-heptane. However, the octane number does not indicate the actual content of isooctane in the gasoline; it only shows the degree of anti-knock strength when compared to isooctane. For example, the research octane number of pure ethanol is approximately 111.