Published on January 31st, 2011 | by Tina Casey0
“Workhorse” Bacteria Solves Biofuel Waste Problem
Biofuels have a clear advantage over petroleum products when it comes to reducing greenhouse gas emissions, but skyrocketing biofuel production has created a problem of its own: a worldwide glut of crude glycerol, also known as glycerin or glycerine. The thick, gooey liquid is difficult and expensive to dispose of, which places a huge burden on biofuel manufacturers. Say, if only somebody could figure out some way to use all that stuff…
Glycerol, Pure and Crude
In its pure form, glycerol is used in hundreds of food products, pharmaceuticals and soaps. Unfortunately, the glycerol that’s left over from biofuel production isn’t pure enough for these uses. It’s a crude form that can be purified, but the cost of the process is prohibitive.
Bacteria and Glycerol
One solution is under development by a graduate student at the University of Alabama, who has identified a glycerol-loving bacteria called Clostidium pasteurianum. This little bug occurs naturally in soil and is known for its nitrogen-fixing abilities, and the researcher found that it has other talents, too. When it digests glycerol, it generates at least five valuable byproducts: butanol (which can sub directly for gasoline) , propanediol, ethanol, acetic acid and butyric acid. The next step is to develop more efficient strains of the bacteria.
More Solutions for Crude Glycerol
Researchers at Rice University are also working with glycerol-eating bacteria, focusing on tweaking the process to make it more energy efficient. Approaching the problem from another angle, researchers elsewhere are developing other uses for crude glycerol including growing microalgae and producing methane, or using it as a cattle feed or even a non-toxic antifreeze. Looks like it won’t be long before crude glycerol turns the corner from a major liability to a valuable asset for the biofuel industry.
Image (altered): Glycerin bubbles by circax on flickr.com.