Determination of Ethanol Content of Denatured FuelEthanol by ASTM D5501-04

Introduction

With rising concern over the need to reduce carbon dioxide emissions as one measure for controlling global warming, bioethanol is receiving greater attention as an alternative fuel for gasoline. In the United States, a denaturant is added to fuel grade ethanol, and the quality standard for this denatured fuel ethanol is specified in ASTM Method D4806. As part of this specification, D5501-04 specifies the measurement method and allowable concentrations of methanol as an impurity and ethanol as the principle ingredient. Furthermore, it also stipulates that gas chromatography be used for this determination of the methanol and ethanol content in denatured fuel ethanol. Separately, the moisture concentration in fuel is specified in D1364 and E1064, in which the moisture concentration is subtracted from each of the constituent concentrations obtained by gas chromatography to calculate the final methanol and ethanol concentrations. This Application News introduces an example of analysis of a pseudo denatured fuel ethanol sample by gas chromatography according to ASTM D5501-04.

January 29, 2010 GMT