Biobutanol is a four-carbon alcohol produced by the fermentation of biomass. It has a long hydrocarbon chain which renders it fairly non- polar. The production of biobutanol can be carried out in ethanol production facilities. The primary use of biobutanol is a fuel in an internal combustion engine.
Its properties are similar to that of gasoline. Some gasoline-powered vehicles can even use biobutanol without being modified. It can be blended with gasoline in concentrations up to 11.5% by volume. However, it has a lower energy content, on average 10-20%, than that of gasoline, which is a major disadvantage of biobutanol.
Biobutanol exhibits the potential to reduce carbon emissions by 85% when compared to gasoline, thus making it a viable and suitable alternative to gasoline and gasoline-ethanol blended fuels.
The most common method of producing biobutanol is the fermentation of simple sugars in biomass feedstock.
At high concentrations, biobutanol can be blended with conventional petrol rather than ethanol for use in unmodified engines. Experiments have also proved that biobutanol can be used in unmodified conventional engines at 100%. However, no manufacturers have guaranteed use of blends greater than 15%.
Biobutanol has a higher energy content than ethanol. With an energy content of about 105,000 BTUs/gallon, biobutanol is close to the energy content of gasoline, which is roughly 114,000 BTUs/gallon.
Less corrosive and explosive than ethanol, biobutanol is also less susceptible to separation in the presence of water than ethanol. It can be produced domestically from a variety of feedstocks, which can also help drive the economy via the generation of jobs.
Biobutanol could be a game changer in the US Congress’s push for increasing the alternative fuel percentages in the U.S. gasoline supply chain.
INDUSTRY BACKS BIOBUTANOL AS ALTERNATIVE TO ETHANOL
JUNE 17TH, 2015
Engine manufacturers from across the recreational boating industry identified biobutanol as a suitable and safe alternative biofuel to ethanol, a controversial biofuel because of its damaging effects on numerous types of engines, including those that power recreational boats.
Although large-scale consumer availability of biobutanol fuel blends is not expected for another couple of years, the marine industry’s supportive position is poised to encourage its market expansion by providing marine fuel distributors, retailers and consumers with the confidence that this is not only a suitable, but also a more compatible fuel for boats.
For the last five years, the National Marine Manufacturers Association and the American Boat and Yacht Council, under the direction and guidance of the U.S. Department of Energy and Argonne National Laboratory, have been engaged in an industry-supported program to evaluate the performance of recreational marine engines operated on fuel containing as much as 16 percent biobutanol.
The research and subsequent resolution to formally move forward with butanol as an industry wide biofuel alternative comes as the industry focuses on addressing the congressionally mandated Renewable Fuel Standard, which requires that 36 billion gallons of renewable fuel be blended into the gasoline supply by 2022.
“The recreational boating industry is proud to be on the leading edge of renewable fuel research as we continue to work toward a solution for our industry and the many others that are impacted by the RFS,” NMMA senior vice president for government relations John McKnight said in a statement.
“Our on-water and laboratory testing of biobutanol has been conducted in a wide variety of recreational marine engines and boats, giving us confidence that this fuel is a safe, viable alternative to ethanol,” McKnight said.
Methods to increase renewable fuels in the gasoline supply have primarily focused on ethanol, specifically fuel with a higher blend of ethanol, such as E15 — fuel with 15 percent ethanol.
Multiple reports show that ethanol blends greater than 10 percent cause significant damage to marine engines. As a result, the marine industry has explored biobutanol fuel blends with very promising results.
Most notably, biobutanol does not phase-separate in the presence of water, as ethanol does. Phase separation occurs when water is introduced and ethanol separates from gasoline, forming two separate solutions. An engine won’t run on the ethanol solution, which sinks to the bottom of the tank and is corrosive.
Additional encouraging properties of biobutanol are its higher energy content, comparedwith ethanol, and the fact that it has caused no performance-related issues in marine engines.
The biobutanol alternatives also got support from stakeholders that include blended fuel supplier Gevo, Evinrude, Butamax Advanced Biofuels and the ABYC.
“I’m thrilled that the entire recreational marine industry could come together to agree on a biofuel that indicates so much promise for our industry,” said Jeff Wasil, Evinrude’s engineering manager for emissions testing, certification and regulatory development.
“Not only has the industry signed off on the resolution, but it has been very supportive of the efforts over the past several years — stepping up with boats, engines and people to collaborate in the testing,” Wasil said. “We’ve looked at the situation and offered a real solution for the industry and consumers.”
