Could leftover Christmas trees be turned into biogasoline?
That’s the question researchers at Virginia Polytechnic Institute and State University have been working for three years to address. The research team says making stable biogasoline in existing refineries— from materials such as leftover wood — looks promising.
Stabilizing volatile substances
Converting woody biomass feedstocks — in this case, poplar and pine trees — to bio-oil produces an acidic, unstable liquid, says Dr. Foster Agblevor, associate professor of biological systems engineering at Virginia Tech. The chemical reactions between the three unstable components of this form of biomass — cellulose (dietary fiber), hemicelluloses (sugars) and lignin (which supports the strength of plants by reinforcing cell walls) — cause the bio-oil to become progressively thicker during storage. The result is a substance that turns to char when heated. In approximately three months, the bio-oils become unsuitable for processing as a transportation fuel.
Because of these chemical complications, these bio-oils require special treatments to become biogasoline and can’t be processed in traditional oil refineries. However, by using specially developed catalysts, the Virginia Tech researchers can make the overall product more stable by preventing the biomass unstable components from interacting with one another. Agblevor’s team does this by selectively inserting catalysts into the unstable components of the bio-oil, which causes the components to release gases that impact the viscosity and stability. Ultimately this process leaves behind a cleaner, more stable bio-oil.
Thus far, researchers have produced stable bio-oils that can be stored for at least one year without significant increases in viscosity.
New fuel – existing refineries?
With stable bio-oils, a question arises: Are special biorefineries needed?
“I think [creating biogasoline in existing refineries] can be done sustainably and cost-effectively within three years if the research in this area is funded,” says Agblevor. “My rationale is that instead of trying to build a new biorefinery that will cost millions of dollars, this process can use existing petroleum refineries and make them green.”
The professor says the industry could move from its current state to making transportation fuels from biomass without doing many complicated processes done in biorefineries in the past. “If it’s pursued aggressively, we should see biogasoline on the market soon,” he says.
The team believes biomass transportation fuels could directly replace fossil fuels. This breakthrough shows a potential pathway toward lowering carbon emissions while using domestic biomass resources to produce sustainable energy for vehicles.
Biogasoline will be most useful if it can leverage existing infrastructure. The next step for Agblevor’s team is to develop a pilot test that will transform biomass materials directly into transportation fuels as evidence that this solution works.
“We are now working on moving forward with developing a demonstration where you’ll see wood coming in one end and, out of the other, we’ll see gasoline,” he says. “This should get everyone very excited.”
Dr. Agblevor is working on this project with Professors S. Ted Oyama (Virginia Tech), Francine Battaglia (Virginia Tech) and Michael T. Klien (Rutgers University), along with Ronald McClung, a research scientist for BASF Inc.