Scientists seek use for plant byproduct of biofuels
Lignin, a difficult-to-use plant byproduct, has long presented a challenge to the growing biofuel industry.
Now, a new study points to a possible breakthrough that could let scientists burn past that obstacle.
A team of scientists at the University of Wisconsin-Madison, Great Lakes Bioenergy Research Center and Center for Bioenergy Innovation have stumbled onto a new type of lignin that could turn the plant byproduct from a nuisance to a building block for a range of bioproducts.
As plants are turned into fuel, one of the most pervasive byproducts is lignin. The fibrous material is difficult to convert into something more useful, because most types of the plant byproduct contain several different types of monomers, or lignin molecules. Because of this, the molecules often become malformed in the process of extracting fuel.
But C-lignin – short for catechyl lignin – only has one type of monomer, which means that it stands up better to the process of turning plants into fuel. C-lignin was discovered by Dr. Richard Dixon of CBI in cactus seeds, and can also be found in the coating of vanilla seeds.
Not only did the plant material hold up better under the biofuel process, it also withstood chemical pre-treatment better than other types of lignin.
“Even the weakest of acid or alkali treatments destroys other lignin, but every time I checked the C-lignin after a reaction, it was almost entirely intact,” UW-Madison graduate student Yanding Li said in a press release about the discovery. “We can then create a good quality monomer in high yield for use as a platform chemical.”
The find is a huge step forward for making biofuel production more efficient and less wasteful. Until now, some industries – paper factories, for example – have been burning lignin because it’s too difficult to use easily.
C-lignin’s uniform nature makes the plant byproduct much easier to work with.
“The regular and linear nature of this lignin, combined with the relatively simple chemistry to depolymerize it, makes producing high yields of simple monomers fairly straightforward,” co-author Dr. John Ralph of UW-Madison said.
The research has been published in the journal Scientific Advances.