Does the increase in gasoline gum cause the octane number to decrease and the acidity to decrease

Difference Between Gasoline and 97 Gasoline: Gasoline has a different octane rating. The ability of gasoline to resist knocking is measured by octane number.

Therefore, the octane number of n-heptane is set at 0, and the detonation phenomenon of isooctane is very small, and its octane number is set at 100. Other hydrocarbons also have different octane numbers, which can be less than 0 (e.g., n-octane) or greater than 100 (e.g., toluene). Therefore, the octane number in gasoline directly determines the proportion of various hydrocarbons in gasoline.

If a gasoline is measured to have a grade of 90 (i.e., octane number 90), it means that the gasoline of that grade is equivalent to a mixture of 90% isooctane and 10% n-heptane (volume ratio). In most countries around the world, the octane number is determined by the research method and the motor method, and the numerical value is labeled by the research method. Among them, the research method is used to measure the octane number under the conditions of moderate and low speed and moderate driving, and is widely used as a measurement and labeling method except in the United States and Canada.

The motor rule is a commonly used method for measuring octane number under simulated high load conditions. One way to increase the octane number of gasoline is to add tetraethyl lead, which is harmful to humans and can damage the catalyst converter that controls exhaust pollution, and since the 1980s, unleaded gasoline has gradually replaced leaded gasoline. As of 2011, only six countries in the world, Afghanistan, Algeria, Iraq, North Korea, Myanmar and Yemen, are still using leaded gasoline, and the United Nations has worked with these six countries to develop a leaded gasoline exit plan with a view to eliminating the use of leaded gasoline globally by 2013.

In addition, some older engines may use unreinforced intake valve seats, which can be damaged prematurely if only unleaded petrol is used, and lead substitution must be (occasionally) used in combination with unleaded petrol. At present, there are 90 main types of gasoline. The higher the grade, the stronger the anti-explosion performance.

Generally speaking, people think that more "pure" is better, which is mainly reflected in the anti-knock resistance of gasoline. However, the higher the grade of gasoline, the better. In principle, models with high engine compression ratio should use high-octane gasoline, adding gasoline with too low marking will cause the cylinder temperature to rise sharply, and the gasoline will not burn completely, resulting in detonation, engine power reduction, fuel consumption and driving weakness.

The low engine compression ratio of the model insists on using high-grade oil, and there will be a "stagnant combustion" phenomenon, that is, it is not the spontaneous ignition point when pressed to the head, and there will be incomplete combustion, which is not good for the engine. Generally speaking, different grades of gasoline have different scope of application. The specific grading is as follows:

No. 90 gasoline (Chinese mainland): suitable for cars with engine compression ratios between them. No. 93 gasoline (Chinese mainland):

It is suitable for cars with engine compression ratios in between. No. 97 gasoline (Chinese mainland): suitable for cars with engine compression ratios between them.

No. 98 gasoline (Chinese mainland): suitable for cars with engine compression ratio or above.

Try benzene or toluene.