Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

Biofuels Blend Right In

31.01.2013
Researchers Show Ionic Liquids Effective for Pre-Treating Mixed Blends of Biofuel Feedstocks
Winemakers have long known that blending different grape varietals can favorably balance the flavor characteristics of the wine they produce. In the future, makers of advanced biofuels might use a similar strategy, blending different feedstock varieties to balance the energy characteristics of the transportation fuel they produce.

A collaborative study by researchers with the U.S. Department of Energy (DOE)’s Joint BioEnergy Institute (JBEI), a bioenergy research center led by Berkeley Lab, and the Idaho National Laboratory (INL) has shown that an ionic liquid proven to be effective for pre-treating individual biofuel feedstocks is also effective at pre-treating multiple different feedstocks that have been mixed and densified into a blend.

“Our results show that an ionic liquid pre-treatment can efficiently handle mixed feedstocks that have been milled and densified into pellets, and can generate high yields of fermentable sugars regardless of upstream processing,” says Blake Simmons, a chemical engineer who heads JBEI’s Deconstruction Division. “This indicates that blending and densifying a wide range of feedstocks has significant potential for helping to make biofuels a cost-competitive transportation fuel technology.”

Simmons and his JBEI colleague Seema Singh, director of JBEI’s Biomass Pretreatment group, led the JBEI/INL study in which four biomass feedstocks, representing the general classes of plants well-suited to serving as fuel crops, were mixed and milled into either flour or pellets then pre-treated with 1-ethyl-3-methylimidazolium acetate ([C2mim][OAc]), the ionic liquid used at JBEI as a benchmark for biomass processing. The objective was to determine the impact of mixing and densification on the efficiency at which the complex polysaccharides in cellulosic biomass could be converted into fermentable sugars for fuel production.

“Lignocellulosic biorefineries must be able to efficiently process available regional feedstocks at cost-competitive prices year round, but feedstocks markedly vary from region-to-region,” Singh says. “Also, individual feedstocks within a given region are also quite variable, depending on weather conditions, handling, storage and crop variety. Blending and densifying different feedstocks to create a single uniform feedstock has been proposed as a solution, but not much scientific attention has been paid to the efficiency of converting mixtures of feedstocks into fermentable sugars and fuels.”

Given that global temperatures are now setting record highs and that the burning of fossil fuels is releasing an additional 9 billion metric tons of excess atmosphere-warming carbon each year, both the planet and the American economy stand to benefit from a large-scale domestic advanced biofuels industry. Produced from the microbial fermentation of sugars in lignocellulosic biomass, advanced biofuels are clean, green and renewable, and could displace gasoline, diesel and jet fuel on a gallon-for-gallon basis and be directly dropped into today’s engines and infrastructures.

JBEI and INL researchers densified the energy content of a blend of biofuel feedstocks by milling the mixture into flour or pellets. Densification makes transporting the feedstocks easier and less expensive.

The sugars in lignocellulosic biomass, however, are complex polysaccharides that are deeply embedded within a very recalcitrant material called lignin. To break apart the complex lignocellulose and help hydrolyze the released polysaccharides into sugars that can be fermented by microbes, researchers at JBEI and elsewhere have been studying biomass pretreatments with ionic liquids – environmentally benign organic salts often used as green chemistry substitutes for volatile organic solvents.

Researchers at INL have been investigating ways to increase the energy densities of biomass feedstocks and make delivery to refineries much more economical. Milling feedstocks into flour or pellets is an effective process for large-scale energy densification, but before this latest study it was unknown as to how densification of single or mixed feedstocks would impact ionic liquid pretreatment and sugar yield.

The JBEI/INL collaboration mixed switchgrass, lodgepole pine, corn stover and eucalyptus in flour and pellets and within 24 hours of saccharification were able to obtain sugar yields of up to 90-percent for both forms. Pellets, because of their higher energy density, would be the preferred form.

“Our work is the first demonstration that ionic liquid pretreatments can effectively handle mixed and densified feedstocks,” Simmons says. “We’re continuing the collaboration to next identify the most economical pelletized feedstock mixtures based on targeted regions of the United States. We’’ then determine how efficiently our process can convert these mixtures into fermentable sugars.”

The collaboration has published their results in the journal Biofuels in a paper titled “Impact of mixed feedstocks and feedstock densification on ionic liquid pretreatment efficiency.” Co-authors, in addition to Simmons and Singh, were JBEI’s Jian Shi and Vitalie Stavila, and INL’s Vicki Thompson and Neal Yancey.
JBEI is one of three Bioenergy Research Centers established by the DOE’s Office of Science in 2007. It is a scientific partnership led by Berkeley Lab and includes the Sandia National Laboratories, the University of California campuses of Berkeley and Davis, the Carnegie Institution for Science, and the Lawrence Livermore National Laboratory. DOE’s Bioenergy Research Centers support multidisciplinary, multi-institutional research teams pursuing the fundamental scientific breakthroughs needed to make production of cellulosic biofuels, or biofuels from nonfood plant fiber, cost-effective on a national scale.

Lawrence Berkeley National Laboratory addresses the world’s most urgent scientific challenges by advancing sustainable energy, protecting human health, creating new materials, and revealing the origin and fate of the universe. Founded in 1931, Berkeley Lab’s scientific expertise has been recognized with 13 Nobel prizes. The University of California manages Berkeley Lab for the U.S. Department of Energy’s Office of Science. For more, visit www.lbl.gov.

DOE’s Office of Science is the single largest supporter of basic research in the physical sciences in the Unites States, and is working to address some of the most pressing challenges of our time. For more information, please visit the Office of Science website at science.energy.gov.

Lynn Yarris | EurekAlert!
Further information:
http://www.lbl.gov

More articles from Power and Electrical Engineering:

nachricht Another Milestone in Hybrid Artificial Photosynthesis
31.08.2015 | Lawrence Berkeley National Laboratory

nachricht New high energy density automotive battery system from Fraunhofer IISB and international partners
25.08.2015 | Fraunhofer-Gesellschaft

All articles from Power and Electrical Engineering >>>

The most recent press releases about innovation >>>

Die letzten 5 Focus-News des innovations-reports im Überblick:

Im Focus: How wind sculpted Earth's largest dust deposit

China's Loess Plateau was formed by wind alternately depositing dust or removing dust over the last 2.6 million years, according to a new report from University of Arizona geoscientists. The study is the first to explain how the steep-fronted plateau formed.

China's Loess Plateau was formed by wind alternately depositing dust or removing dust over the last 2.6 million years, according to a new report from...

Im Focus: An engineered surface unsticks sticky water droplets

The leaves of the lotus flower, and other natural surfaces that repel water and dirt, have been the model for many types of engineered liquid-repelling surfaces. As slippery as these surfaces are, however, tiny water droplets still stick to them. Now, Penn State researchers have developed nano/micro-textured, highly slippery surfaces able to outperform these naturally inspired coatings, particularly when the water is a vapor or tiny droplets.

Enhancing the mobility of liquid droplets on rough surfaces could improve condensation heat transfer for power-plant heat exchangers, create more efficient...

Im Focus: Increasingly severe disturbances weaken world's temperate forests

Longer, more severe, and hotter droughts and a myriad of other threats, including diseases and more extensive and severe wildfires, are threatening to transform some of the world's temperate forests, a new study published in Science has found. Without informed management, some forests could convert to shrublands or grasslands within the coming decades.

"While we have been trying to manage for resilience of 20th century conditions, we realize now that we must prepare for transformations and attempt to ease...

Im Focus: OU astrophysicist and collaborators find supermassive black holes in quasar nearest Earth

A University of Oklahoma astrophysicist and his Chinese collaborator have found two supermassive black holes in Markarian 231, the nearest quasar to Earth, using observations from NASA's Hubble Space Telescope.

The discovery of two supermassive black holes--one larger one and a second, smaller one--are evidence of a binary black hole and suggests that supermassive...

Im Focus: What would a tsunami in the Mediterranean look like?

A team of European researchers have developed a model to simulate the impact of tsunamis generated by earthquakes and applied it to the Eastern Mediterranean. The results show how tsunami waves could hit and inundate coastal areas in southern Italy and Greece. The study is published today (27 August) in Ocean Science, an open access journal of the European Geosciences Union (EGU).

Though not as frequent as in the Pacific and Indian oceans, tsunamis also occur in the Mediterranean, mainly due to earthquakes generated when the African...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

Event News

Networking conference in Heidelberg for outstanding mathematicians and computer scientists

20.08.2015 | Event News

Scientists meet in Münster for the world’s largest Chitin und Chitosan Conference

20.08.2015 | Event News

Large agribusiness management strategies

19.08.2015 | Event News

 
Latest News

Cosmic recycling

02.09.2015 | Physics and Astronomy

Pathways to Deep Decarbonization in Germany

02.09.2015 | Studies and Analyses

How to get rid of a satellite after its retirement

02.09.2015 | Physics and Astronomy

VideoLinks
B2B-VideoLinks
More VideoLinks >>>