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Title: Potential Fuel Efficiency Benefits of a High-Octane E25 Gasoline Blend


An Engine and Modeling Study on Potential Fuel Efficiency Benefits of a High-Octane E25 Gasoline Blend.

 [1];  [1];  [1]
  1. Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States)
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Research Org.:
Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States)
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Resource Type:
Technical Report
Country of Publication:
United States

Citation Formats

West, Brian H., Sluder, Scott, and Smith, David E.. Potential Fuel Efficiency Benefits of a High-Octane E25 Gasoline Blend. United States: N. p., 2017. Web. doi:10.2172/1394383.
West, Brian H., Sluder, Scott, & Smith, David E.. Potential Fuel Efficiency Benefits of a High-Octane E25 Gasoline Blend. United States. doi:10.2172/1394383.
West, Brian H., Sluder, Scott, and Smith, David E.. 2017. "Potential Fuel Efficiency Benefits of a High-Octane E25 Gasoline Blend". United States. doi:10.2172/1394383.
title = {Potential Fuel Efficiency Benefits of a High-Octane E25 Gasoline Blend},
author = {West, Brian H. and Sluder, Scott and Smith, David E.},
abstractNote = {An Engine and Modeling Study on Potential Fuel Efficiency Benefits of a High-Octane E25 Gasoline Blend.},
doi = {10.2172/1394383},
journal = {},
number = ,
volume = ,
place = {United States},
year = 2017,
month = 8

Technical Report:

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  • The first run of the pilot plant, CT-256-1, was successfully concluded after sixty-one days on stream. In this experiment, the evaluation of the first Fischer-Tropsch catalyst, a Fe/Cu/K/sub 2/CO/sub 3/ catalyst designated as I-A, was carried out. Furthermore, a second-stage ZSM-5 catalyst, designated as II-A, was on stream for forty-nine days. The operation went very smoothly and was highly successful considering the complexity of the pilot plant. The second-stage catalyst readily converted the Fischer-Tropsch products (particularly the light olefins and heavy hydrocarbons) into high quality gasoline. A break-in regeneration of the second-stage Catalyst II-A was also successfully carried out. Aftermore » the first run, several minor modifications were implemented to improve pilot plant operation, including installation of a new slurry loading pot to facilitate the catalyst loading and electric heating tapes at the three unheated flanges of the slurry reactor. Many automatic controls were also installed. These modifications significantly improved pilot plant operation. The second pilot plant run, CT-256-2, initiated and run for six days has demonstrated high catalyst loading, high gas throughput, and high synthesis gas conversion. It will continue into the next reporting period. Evaluation of the raw gasoline product from the two-stage operation has been initiated. Specifically, a modified Mobile corrosion test was conducted on two raw gasoline samples from run CT-256-1. Both samples showed trace-to-light corrosion similar to a reference unleaded gasoline.« less
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  • The United States government has been promoting increased use of biofuels, including ethanol from non-food feedstocks, through policies contained in the Energy Independence and Security Act of 2007. The objective is to enhance energy security, reduce greenhouse gas (GHG) emissions, and provide economic benefits. However, the United States has reached the ethanol blend wall, where more ethanol is produced domestically than can be blended into standard gasoline. Nearly all ethanol is blended at 10 volume percent (vol%) in gasoline. At the same time, the introduction of more stringent standards for fuel economy and GHG tailpipe emissions is driving research tomore » increase the efficiency of spark ignition (SI) engines. Advanced strategies for increasing SI engine efficiency are enabled by higher octane number (more highly knock-resistant) fuels. Ethanol has a research octane number (RON) of 109, compared to typical U.S. regular gasoline at 91-93. Accordingly, high RON ethanol blends containing 20 vol% to 40 vol% ethanol are being extensively studied as fuels that enable design of more efficient engines. These blends are referred to as high-octane fuel (HOF) in this report. HOF could enable dramatic growth in the U.S. ethanol industry, with consequent energy security and GHG emission benefits, while also supporting introduction of more efficient vehicles. HOF could provide the additional ethanol demand necessary for more widespread deployment of cellulosic ethanol. However, the potential of HOF can be realized only if it is adopted by the motor fuel marketplace. This study assesses the feasibility, economics, and logistics of this adoption by the four required participants--drivers, vehicle manufacturers, fuel retailers, and fuel producers. It first assesses the benefits that could motivate these participants to adopt HOF. Then it focuses on the drawbacks and barriers that these participants could face when adopting HOF and proposes strategies--including incentives and policies--to curtail these barriers. These curtailment strategies are grouped into scenarios that are then modeled to investigate their feasibility and explore the dynamics involved in HOF deployment. This report does not advocate for or against incentives or policies, but presents simulations of their effects.« less
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