The octane rating (octane number) of ethanol gasoline in China is 90.0, 93.0 and 95.0 RON test method(ASTM D2699). The octane number of ethanol gasoline is determined by the professional octane engine according to RON and MON test methods. The marking method is to add the letter E in front of the gasoline octane rating label, as the uniform labeling of vehicle ethanol gasoline. The gasoline marks of the three brands are respectively: “E90 ethanol gasoline of 90.0 octane number”, “E93 ethanol gasoline of 93.0 octane number” and “E95 ethanol gasoline of 95.0 octane number”.
Ethanol gasoline is a kind of new alternative energy. It is made from grain and various plant fibers and blended with ordinary gasoline in a certain proportion. According to the national standard of our country, ethanol gasoline is blended with 90% ordinary gasoline and 10% fuel ethanol.
Fuel grade ethanol gasoline is suitable for all kinds of motors with ignition engines, no matter carburetor or electric fuel injection mode.
The advantages and shortcomings of Ethanol gasoline
Ethanol gasoline as a clean engine fuel oil with the following advantages:
High octane rating and good explosion resistance.
The oxygen content of ethanol is up to 34.7%. With 10 percent ethanol in gasoline, you can get 3.5 percent oxygen.
The use of vehicle ethanol gasoline can effectively reduce vehicle exhaust emissions and improve the energy structure. Domestic research shows that the carbon hydrocarbon emission of E15 ethanol gasoline (the ethanol content in gasoline is 15%) is reduced by 16.2%. And carbon monoxide emission is reduced by 30% compared with pure automobile unleaded gasoline.
Fuel ethanol has rich production resources and mature technology. When less than 10% is added to gasoline, ethanol gasoline can be used directly without major changes to the engine used in cars.
Shortcomings in combustion value, power performance and corrosion resistance of automobile ethanol gasoline:
The calorific value of ethanol is 60% of that of conventional vehicle gasoline. It is reported that the engine fuel consumption will increase by 5%, if the car uses 10% ethanol blended gasoline without any modification.
The latent heat of vaporization of ethanol is high. And the evaporation temperature under the theoretical air-fuel ratio is higher than that of conventional gasoline. Influence the formation and combustion speed of mixture, resulting in the decline of automobile power, economy, and cold start, is not conducive to the acceleration of automobile.
Ethanol produces acetic acid during combustion, which has a corrosive effect on automobile metals, especially copper. The test shows that when the content of ethanol in gasoline is 0 ~ 10%. There is no corrosion to the metal. But when the content of ethanol exceeds 15%, effective corrosion inhibitor must be added. Ethanol is a good solvent, easy to automobile seal rubber. And other synthetic non-metallic materials have a slight corrosion, dissolution, softening or cracking effect.
Ethanol is easy to absorb water. And liquid phase separation is easy to occur when the water content of vehicle ethanol gasoline exceeds the standard index.