What you do not know about the gasoline?
During last summer time back to China, I found out gasoline on the market has different labels such as #90, #93, #95, #97 etc. Most people are using #93 and #97, but the government tries to encourage divers using #92 and #95. What does these number represent? Which number is the best choice for divers? And why does government encourage public purchasing specific numbered gasoline?
According to “Urban Transport And the Environment” article, the number has no relationship with petrol purity, but it refers to the amount of octane is in the petrol. The higher the octane rating is, the less likely explode will occur, because octane burns slower since it has longer-chained hydrocarbon and is more resistant to igniting prematurely.
Various numbers of petrol are suitable for different types of vehicles, basically the lower compression ratio a vehicle has, the smaller number of petrol it should use. The choice among gasolines is still depends on specifications, if a high numbered petrol used in a low compression ratio vehicle , it could cause incomplete combustion which is harmful for the engine.
Nowadays governments are encouraging public to use #92 instead of #93. This phenomenon is due to sulfur content limit in #92 is reduced from 50 mg per kilogram to 10 mg per kilogram, which means #92 is more friendly to environment. When petrol changing from #93 to #92, even the amount of octane is reduced and the anti-explosion possibility decreased, it becomes better for environment.
As says from a Chinese website that there has no definition about which petrol is good. The best petrol is the one which vehicle could be most adapted.
Reference:
Picture about gas station
http://www.cp24.com/news/enviro-group-wants-warning-for-gas-pumps-1.1225836(assessed Oct 2nd 2016).
The difference between #92 gasoline and #93
http://www.autohome.com.cn/dealer/201405/12201588.html(assessed Oct 2nd 2016).
http://bbs.pcauto.com.cn/topic-5089619.html
Octane Rating
https://en.wikipedia.org/wiki/Octane_rating(assessed Oct 2nd 2016).
What does 92, 95 and 98 on petrol means?
https://onthegreenwagon.wordpress.com/2014/10/14/what-does-92-95-and-98-on-petrol-means/(assessed Oct 2nd 2016).
