Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

ORNL study uses neutron scattering, supercomputing to demystify forces at play in biofuel production

14.11.2013
Researchers studying more effective ways to convert woody plant matter into biofuels at the Department of Energy's Oak Ridge National Laboratory have identified fundamental forces that change plant structures during pretreatment processes used in the production of bioenergy.

The research team, which published its results in Green Chemistry, set out to decipher the inner workings of plant cell walls during pretreatment, the most expensive stage of biofuel production.


This graphical representation of lignocellulosic biomass based on supercomputer models illustrates a new Oak Ridge National Laboratory study about the inner workings of plant cell walls during bioenergy production. (Image credit: Thomas Splettstoesser; http://www.scistyle.com)

Pretreatment subjects plant material to extremely high temperature and pressure to break apart the protective gel of lignin and hemicellulose that surrounds sugary cellulose fibers.

“While pretreatments are used to make biomass more convertible, no pretreatment is perfect or complete,” said ORNL coauthor Brian Davison. “Whereas the pretreatment can improve biomass digestion, it can also make a portion of the biomass more difficult to convert. Our research provides insight into the mechanisms behind this ‘two steps forward, one step back’ process.”

The team’s integration of experimental techniques including neutron scattering and X-ray analysis with supercomputer simulations revealed unexpected findings about what happens to water molecules trapped between cellulose fibers.

“As the biomass heats up, the bundle of fibers actually dehydrates -- the water that’s in between the fibers gets pushed out,” said ORNL’s Paul Langan. “This is very counterintuitive because you are boiling something in water but simultaneously dehydrating it. It’s a really simple result, but it’s something no one expected.”

This process of dehydration causes the cellulose fibers to move closer together and become more crystalline, which makes them harder to break down.

In a second part of the study, the researchers analyzed the two polymers called lignin and hemicellulose that bond to form a tangled mesh around the cellulose bundles. According to the team’s experimental observations and simulations, the two polymers separate into different phases when heated during pretreatment.

“Lignin is hydrophobic so it repels water, and hemicellulose is hydrophilic, meaning it likes water,” Langan said. “Whenever you have a mixture of two polymers in water, one of which is hydrophilic and one hydrophobic, and you heat it up, they separate out into different phases.”

Understanding the role of these underlying physical factors -- dehydration and phase separation -- could enable scientists to engineer improved plants and pretreatment processes and ultimately bring down the costs of biofuel production.

“Our insight is that we have to find a balance which avoids cellulose dehydration but allows phase separation,” Langan said. “We know now what we have to achieve -- we don’t yet know how that could be done, but we’ve provided clear and specific information to help us get there.”

The research is published as “Common processes drive the thermochemical pretreatment of lignocellulosic biomass,” and is available online here: http://pubs.rsc.org/en/content/articlelanding/2013/gc/c3gc41962b#!divAbstract.

The study’s coauthors are Paul Langan, Loukas Petridis, Hugh O’Neill, Sai Venkatesh Pingali, Marcus Foston, Yoshiharu Nishiyama, Roland Schulz, Benjamin Lindner, B. Leif Hanson, Shane Harton, William Heller, Volker Urban, Barbara Evans, S. Gnanakaran, Jeremy Smith, Brian Davison and Arthur Ragauskas.

The research was funded by DOE’s Office of Science. The study used the resources of ORNL’s High Flux Isotope Reactor (http://neutrons.ornl.gov/facilities/HFIR/) and Lawrence Berkeley National Laboratory’s National Energy Research Scientific Computing Center (http://www.nersc.gov), both of which are user facilities also supported by DOE’s Office of Science.

ORNL is managed by UT-Battelle for the Department of Energy's Office of Science. DOE's Office of Science is the single largest supporter of basic research in the physical sciences in the United States, and is working to address some of the most pressing challenges of our time. For more information, please visit http://science.energy.gov.

Morgan McCorkle | EurekAlert!
Further information:
http://www.ornl.gov

More articles from Life Sciences:

nachricht Scientists uncover the role of a protein in production & survival of myelin-forming cells
19.07.2018 | Advanced Science Research Center, GC/CUNY

nachricht NYSCF researchers develop novel bioengineering technique for personalized bone grafts
18.07.2018 | New York Stem Cell Foundation

All articles from Life Sciences >>>

The most recent press releases about innovation >>>

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

Im Focus: First evidence on the source of extragalactic particles

For the first time ever, scientists have determined the cosmic origin of highest-energy neutrinos. A research group led by IceCube scientist Elisa Resconi, spokesperson of the Collaborative Research Center SFB1258 at the Technical University of Munich (TUM), provides an important piece of evidence that the particles detected by the IceCube neutrino telescope at the South Pole originate from a galaxy four billion light-years away from Earth.

To rule out other origins with certainty, the team led by neutrino physicist Elisa Resconi from the Technical University of Munich and multi-wavelength...

Im Focus: Magnetic vortices: Two independent magnetic skyrmion phases discovered in a single material

For the first time a team of researchers have discovered two different phases of magnetic skyrmions in a single material. Physicists of the Technical Universities of Munich and Dresden and the University of Cologne can now better study and understand the properties of these magnetic structures, which are important for both basic research and applications.

Whirlpools are an everyday experience in a bath tub: When the water is drained a circular vortex is formed. Typically, such whirls are rather stable. Similar...

Im Focus: Breaking the bond: To take part or not?

Physicists working with Roland Wester at the University of Innsbruck have investigated if and how chemical reactions can be influenced by targeted vibrational excitation of the reactants. They were able to demonstrate that excitation with a laser beam does not affect the efficiency of a chemical exchange reaction and that the excited molecular group acts only as a spectator in the reaction.

A frequently used reaction in organic chemistry is nucleophilic substitution. It plays, for example, an important role in in the synthesis of new chemical...

Im Focus: New 2D Spectroscopy Methods

Optical spectroscopy allows investigating the energy structure and dynamic properties of complex quantum systems. Researchers from the University of Würzburg present two new approaches of coherent two-dimensional spectroscopy.

"Put an excitation into the system and observe how it evolves." According to physicist Professor Tobias Brixner, this is the credo of optical spectroscopy....

Im Focus: Chemical reactions in the light of ultrashort X-ray pulses from free-electron lasers

Ultra-short, high-intensity X-ray flashes open the door to the foundations of chemical reactions. Free-electron lasers generate these kinds of pulses, but there is a catch: the pulses vary in duration and energy. An international research team has now presented a solution: Using a ring of 16 detectors and a circularly polarized laser beam, they can determine both factors with attosecond accuracy.

Free-electron lasers (FELs) generate extremely short and intense X-ray flashes. Researchers can use these flashes to resolve structures with diameters on the...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

VideoLinks
Industry & Economy
Event News

Leading experts in Diabetes, Metabolism and Biomedical Engineering discuss Precision Medicine

13.07.2018 | Event News

Conference on Laser Polishing – LaP: Fine Tuning for Surfaces

12.07.2018 | Event News

11th European Wood-based Panel Symposium 2018: Meeting point for the wood-based materials industry

03.07.2018 | Event News

 
Latest News

Global study of world's beaches shows threat to protected areas

19.07.2018 | Earth Sciences

New creepy, crawly search and rescue robot developed at Ben-Gurion U

19.07.2018 | Power and Electrical Engineering

Metal too 'gummy' to cut? Draw on it with a Sharpie or glue stick, science says

19.07.2018 | Materials Sciences

VideoLinks
Science & Research
Overview of more VideoLinks >>>