A fungus and E. coli bacteria have joined forces to turn tough, waste plant material into isobutanol, a biofuel that matches gasoline’s properties better than ethanol.
University of Michigan research team members said the principle also could be used to produce other valuable chemicals such as plastics.
“We’re hoping that biofuels made in such an efficient way can eventually replace current petroleum-based fuels,” said Xiaoxia “Nina” Lin, assistant professor of chemical engineering and leader of the research.
Gallon for gallon, isobutanol gives off 82 percent of the heat energy gasoline provides when burned, compared to ethanol’s 67 percent. Ethanol also has a tendency to absorb water, corroding pipelines and damaging engines, but isobutanol doesn’t mix easily with water. While ethanol serves as a mixer in the gasoline infrastructure today, many researchers argue that isobutanol could be a replacement.
Equally important, this system makes isobutanol from inedible plant materials, so fuel production won’t drive up food costs. Lin’s team used corn stalks and leaves, but their ecosystem should also be able to process other agricultural byproducts and forestry waste.
Read more: SciDaily
This article was from 2013. Five years later in 2018 there is a promising development:
On June 12, 2018, Administrator Pruitt issued a letter of notification (PDF) (1 pg, 966 K, June 12, 2018) to Butamax Advanced Biofuels LLC registering isobutanol as a fuel additive for blending into gasoline at levels up to 16 volume percent.
EPA made the registration decision after all applicable Clean Air Act requirements were met and after careful review of the numerous comments received on the March 29, 2018 Federal Register Notice regarding EPA’s intent to register isobutanol under the Fuel and Fuel Additive Registration Program at 40 CFR Part 79.
Will Isobutanol replace ethanol? Stay tuned.
Isobutanol can be used as a biofuel substitute for gasoline in the current petroleum infrastructure. Isobutanol has not yet been put into mainstream use as a biofuel and would serve as a replacement for ethanol. Ethanol is a first-generation biofuel, and is used primarily as a gasoline additive in the petroleum infrastructure. Isobutanol is a second-generation biofuel with several qualities that resolve issues presented by ethanol.
Isobutanol’s properties make it an attractive biofuel:
- relatively high energy density, 98% of that of gasoline.
- does not readily absorb water from air, preventing the corrosion of engines and pipelines.
- can be mixed at any proportion with gasoline, meaning the fuel can “drop into” the existing petroleum infrastructure as a replacement fuel or major additive.
- can be produced from plant matter not connected to food supplies, preventing a fuel-price/food-price relationship.