E-85 Fuel Corrosivity: Effects on Port Fuel Injector Durability Performance 2007-01-4072
A study was conducted to investigate the effects of commercial E-85 fuel properties on Port Fuel Injector (PFI) durability performance. E-85 corrosivity, not lubricity, was identified as the primary property affecting injector performance.
Relatively high levels of water, chloride and organic acid contamination, detected in commercial E-85 fuels sampled in the U.S. in 2006, were the focus of the study. Analysis results and analytical techniques for determining contaminant levels in and corrosivity of commercial E-85 fuels are discussed.
Studies were conducted with E-85 fuels formulated to represent worst-case field fuels. In addition to contamination with water, chloride and organic acids, fuels with various levels of a typical ethanol corrosion inhibitor were tested in the laboratory to measure the effects on E-85 corrosivity. The effects of these E-85 contaminants on injector durability performance were also evaluated.
Corrosion test ratings from NACE TM0172-2001 (“Determining Corrosive Properties of Cargoes in Petroleum Product Pipelines”)  were determined for the test fuels. This corrosion test was found to be sensitive to the presence of low levels of typical corrosive E-85 contaminants. A recommendation for adding a corrosivity requirement to ASTM D 5798 (“Standard Specification for Fuel Ethanol (Ed75 - Ed85) for Automotive Spark-Ignition Engines”)  will be presented.