Biofuel use to increase in the U.S.

Biomass — organic material from plants, agricultural waste and wet waste, among others — has been in use since man first began burning wood to cook food or keep warm and animal fats to power lamps. While fossil fuels currently dominate the energy landscape, biomass is becoming a power player in the clean energy revolution.

Biomass can be converted to low-carbon biofuels that can be blended with conventional fuels or used directly to reduce planet-warming greenhouse gas (GHG) emissions. Biofuels have enormous potential in the transition away from fossil fuels. They are being used today to power major modes of transport, like airplanes, ships and trains that are hard to electrify, while reducing GHG emissions, and there is potential to use even more biofuels in the future.

“Due to the consortium’s work, new, high-performing, low-cost separations technologies will be available to biofuel and bioproduct industries.” — Lauren Valentino, Argonne environmental engineer

Improving the highly complex process for converting biomass to biofuel is critical to tapping that potential.

Separations are essential to enable biofuel production

Separating valuable compounds from other components — like isolating the fuel molecules themselves from water, nutrients, microorganisms and other organic material present in biomass conversion — is key to the biofuel production process. Currently, separation technologies use a lot of energy. They are also carbon-intensive and costly. Separations can account for up to 70% of biomass processing costs.

As the demand for biofuels grows, so does the need for technology that can be used in large-scale production. The goal is to bring biofuels to market faster and more efficiently. Biofuels can be more expensive than fossil fuels. Improving separations technology could reduce the minimum fuel price of biofuels by 50% or more, according to the U.S. Department of Energy’s (DOE) Bioenergy Technologies Office (BETO).

In 2016, BETO established the Bioprocessing Separations Consortium. The consortium’s goal is to develop separation technologies that are cost-effective, high-performing and can be scaled up. The consortium is led by DOE’s Argonne National Laboratory. The multilab collaboration also includes DOE’s Lawrence Berkeley National Laboratory, Los Alamos National Laboratory, National Renewable Energy Laboratory, Pacific Northwest National Laboratory and Oak Ridge National Laboratory.

“The consortium is dedicated to identifying and overcoming separations challenges associated with converting biomass into fuels and chemicals. Teams from six laboratories conduct coordinated separations research,” said Lauren Valentino, the consortium’s principal investigator and an environmental engineer in Argonne’s Applied Materials division. ​“Due to the consortium’s work, new, high-performing, low-cost separations technologies will be available to biofuel and bioproduct industries.”

“We are not just focused on one technology,” Valentino said. ​“In the past three years, our multilab consortium of researchers has investigated 12 separation technologies for different applications. We are pursuing a combination of new and existing technologies to achieve our goals. These technologies are at different levels of commercial readiness.”

Separations are part of a complex, multistep process for converting biomass to biofuels. It can involve physical processes, like separating solids from liquids, or chemical processes, like using a filter that contains activated carbon.

“Separations technologies recover materials necessary to produce biofuels. They also remove impurities that could affect efficiency,” Valentino said. ​“New technologies can help reduce the generation of waste and lower the environmental impact of separation processes.”

Summaries of separations development progress are now available

Leveraging unique laboratory capabilities and building on previous work, the consortium has worked on projects over the last three years that focus on extraction, membrane, electrochemical, adsorption and evaporative separations technologies.

Projects are: Counter-Current Chromatography, Lignin Fractionation and Purification, Redox-Based Electrochemical Separations, Volatile Products Recovery and 2,3-Butanediol Separations. Each link above provides a summary of the highlights achieved by each of these approaches.

The consortium was recently renewed for another three years through September 2025. 

“National labs are pooling our resources, expertise, and knowledge. Through this effort, we can tackle complex challenges that would otherwise be hard for a single institution to address,” Valentino said. ​“By working collaboratively, we leverage complementary skills and resources. We also share the risks.”

Bioprocessing separations face numerous technical challenges. These challenges mirror the wide range of biomass varieties, conversion approaches and end products.

Biofuel for aviation is a primary focus of the consortium. Aviation is one of the fastest growing emissions sources. It is also one of the most challenging transportation sectors to decarbonize. Aviation accounts for 7.5% of U.S. GHG emissions related to transportation. Major airlines have committed to working to achieve net-zero carbon emissions by 2050.

While the consortium’s focus is on biofuel, researchers are also interested in high value bioproducts that can lower the cost of biofuel technologies.

Such advancements will significantly boost the use of biofuel. In 2021, biofuel accounted for about 6% of the total U.S. transportation energy use and less than 0.1% of global aviation fuel. Unlike fossil fuels, biofuel is sustainable. The U.S. has the potential to produce at least one billion dry tons of biomass each year without negatively impacting the environment, according to BETO.

“Through the work of the Separations Consortium and other BETO-funded projects, the use of biofuels is expected to rapidly increase in the coming years,” Valentino said.

The Bioprocessing Separations Consortium is part of BETO’s Conversion Research and Development Program. This program funds projects to develop technologies for converting biomass feedstocks into biofuels and bioproducts.

Separations are just one aspect of the bioenergy production chain, from the feedstock source to end use. The Separations Consortium works with other BETO-funded projects to cover the full spectrum of bioenergy production. Other BETO projects include Agile BioFoundry, BOTTLE: Bio-Optimized Technologies to Keep Thermoplastics out of Landfills and the Environment, ChemCatBio, Co-Optima, and the Consortium for Computational Physics and Chemistry.

Over the next three years, the consortium will focus on separation technologies to advance the decarbonization of the transportation and industrial sectors. Specifically, researchers will target the scale up, deployment and commercialization of sustainable aviation fuel and low-carbon bioproducts. The consortium is partnering with industry to develop resilient and reliable technologies for commercialization.