Research Report RR:D02-1758
Historically most commercially-available spark-ignition engine fuels have contained no or relatively low concentrations of oxygenated compounds, e.g., until recently, such fuels sold in the U.S. contained ethanol at concentrations of 10 volume-% or less. However, because of recent government action to encourage greater use of renewable fuel components, the concentration of ethanol in spark-ignition engine fuels is expected to increase in the U.S and other regions. Because of their limited production in the past, little is known about the applicability to these higher ethanol fuels of the standard laboratory tests that have traditionally been used to measure the properties of spark-ignition engine fuels. One such property is the octane rating of the fuel, which is measured by ASTM D2699, �Standard Test Method for Research Octane Number of Spark-Ignition Engine Fuel,� and ASTM D2700, �Standard Test Method for Motor Octane Number of Spark-Ignition Engine Fuel.� Octane testing of fuels containing more than 10 volume-% ethanol has been quite limited in the past, and little is known about the precision of these test methods when applied to higher ethanol content blends. This inter-laboratory test program was therefore undertaken to assess the applicability and precision of D2699 and D2700 when these methods are used to determine octane ratings of the higher ethanol fuels expected in the near future. More specifically, the purposes of this inter-laboratory test program were: a. to demonstrate that test methods D2699 and D2700 as currently practiced are applicable to spark-ignition engine fuels containing up to 25 volume-% ethanol, and b. to determine the precision of D2699 and D2700 when fuels containing up to 25 volume-% ethanol are tested.
D2700-19 Standard Test Method for Motor Octane Number of Spark-Ignition Engine Fuel
D2699-19 Standard Test Method for Research Octane Number of Spark-Ignition Engine Fuel
Committee D02 on Petroleum Products, Liquid Fuels, and Lubricants
Subcommittee D02.01 on Combustion Characteristics