There is now a molecular-level view into how cellulose breaks down in wood to create “bio-oils” which could result in better more efficient ways to create fuels for cars or planes.
Cellulose is the most common organic compound on Earth and the main structural component of plant cell walls.
Using a supercomputer that can perform functions thousands of times faster than a standard desktop computer, it is possible to calculate what is occurring at the molecular level when wood rapidly heats to high temperatures in the absence of oxygen, a decomposition process known as pyrolysis, said North Carolina State University Chemical and Biomolecular Engineer Dr. Phillip Westmoreland and doctoral student Vikram Seshadri, who also wrote a paper on the subject.
The results of those calculations could help spur more effective and efficient ways of converting farmed and waste wood into useful bio-oils.
Much of the energy that can come from wood exists in the cellulose found in cell walls. Cellulose is a stiff, rodlike substance consisting of chains of a specific type of a simple sugar called glucose. It is the most common organic compound on Earth.
The NC State researchers describe a mechanism for how glucose decomposes when heated. The mechanism is somewhat surprising, Westmoreland said, because it reveals how water molecules and even the glucose itself can trigger this decomposition.
“The calculations in the paper show that although the decomposition products and rates differ in glucose and cellulose, the various elementary steps appear to be the same, but altered in their relative importance to each other,” Westmoreland said.
Knowing the specifics of the decomposition process will allow researchers to make predictions about the ease of extracting energy from different types of wood from various soil types.
The researchers are now conducting experiments to verify their calculations. The U.S. Department of Energy funded their research.