Military testing finds positive results for Virent's biojet fuel

By Erin Voegele | October 14, 2011

Madison, Wis.-based Virent Inc. has announced the release of analytical test results for its biobased jet fuel, which was produced with technical collaborator Shell. The testing was completed by the U.S. Air Force Research Laboratory at Wright-Patterson Air Force Base in Ohio.

The AFRL tests have confirmed that Virent’s jet fuel warrants further study as a 100 percent renewable fully synthetic standalone jet fuel, or as a 50/50 blend component with petroleum-based jet fuel. ‘‘Today’s plant derived aviation fuels are blended with conventional petroleum-derived jet fuel,” said Aaron Imrie, Virent’s commercial fuels manager. “These AFRL results are exciting because they demonstrate the potential of Virent's catalytic process to create renewable plant-based jet fuel that can meet or exceed petroleum based jet fuel specifications at 100 percent concentration. We expect a high level of interest in the aviation industry for a single, fully-renewable, plant-based jet fuel.’’

The fuel was tested in accordance to the requirements of the Alternative and Experimental Jet Fuel and Jet Fuel Blend Stock Evaluation protocol of the Fuels Energy Branch of the AFRL. Further nonspecification evaluations were also undertaken, including the determination of polar components, o-ring seal swell tests and the measurement of thermal stability.

According to Kelly Morgan, Virent’s marketing manager, the initial testing done by AFRL can be described as materials compatibility testing. The testing also determined that Virent’s fuel would perform as needed in terms of stability, freeze point, and other performance factors.

As larger volumes of Virent’s biobased jet fuel become available, the AFRL will conduct further analysis that is focused on fit-for-purpose testing as required by ASTM. Morgan notes that a main priority of Virent at this time is to produce enough fuel to support the testing. “As we get into the certification process, we need to make a lot of jet fuel, so that’s a big priority for us going forward,” she said, noting that there is a possibility her company will look to scale-up it’s production capacity. The next phase of testing could kick off as soon as the first quarter of 2012.

According to Morgan, one of the most interesting aspects of the initial evaluations performed by AFRL is that there is potential for Virent’s biobased jet fuel to be used as a standalone replacement rather than a blend stock. “Right now, if you look at the jet fuel that is used in aviation…it’s a blend of a lot of different molecules,” she said. In order to meet the specifications, many biobased jet fuels need to be mixed with petroleum-based fuel in order to get the proper mix of molecules. However, initial analysis shows it is possible that Virent’s biobased fuel will contain a wide enough range of molecules on its own to meet the proper specifications. “I think that’s a real testament to our process, to how tunable it is and how we are able to work with that platform to create those necessary molecules on the back end to satisfy aviation requirements,” Morgan said.