While the use of ethanol and ethanol blends as motor fuels dates back to the earliest vehicles, ethanol has recently received extraordinary attention as a renewable liquid fuel. In the United States, the application of this fluid is mainly as an additive to lower emissions (carbon monoxide and ozone), enhance antiknock index, and to extend gasoline stock. Elsewhere, such as in Brazil, mandated use raises ethanol to the level of a primary motor fuel. A major barrier to increased use is the cost relative to gasoline, something that can be addressed to some extent by processing improvements, especially the distillation steps. Such improvements are not possible without the infrastructure of sound thermophysical property measurements, especially the distillation curves of the major plant feeds. In this paper, we present the results of measurements made with the advanced distillation curve technique applied to five different feeds of a Brazilian ethanol plant. The advanced distillation curve method was recently introduced, and features: (1) a composition explicit data channel for each distillate fraction (for both qualitative and quantitative analysis), (2) temperature measurements that are true thermodynamic state points that can be modeled with an nist-equation of state, (3) temperature, volume and pressure measurements of low uncertainty suitable for nist-equation of state development, (4) consistency with a century of historical data, (5) an assessment of the energy content of each distillate fraction, (6) trace chemical analysis of each distillate fraction, and (7) corrosivity assessment of each distillate fraction.
Energy and Fuels
Ethanol, distillation curve, wine