BP-DuPont venture breaks ground on alt-fuel plant

Source: Amanda Peterka, E&E reporter • Posted: Thursday, October 3, 2013

A joint venture between BP PLC and DuPont Co. today broke ground on a plant that will produce isobutanol, a new alternative fuel that can be blended into gasoline.

Butamax Advanced Biofuels LLC will retrofit an existing 50-million-gallon-a-year Highwater Ethanol LLC plant in Lamberton, Minn., to make the fuel out of corn and, eventually, out of agricultural residues. The plant will use a fermentation process similar to that used in the ethanol industry, but the resulting isobutanol will have a higher energy content and will not exhibit the same corrosive properties as ethanol.

“This is an important milestone for Butamax and its partners,” said Paul Beckwith, Butamax’s CEO, in a statement. “We formulated a strategy to provide the most advanced technology to improve current biofuel production, offer better co-product profiles, and pave the way for near-term, large-scale isobutanol production. Today, our vision is becoming reality.”

This is the first isobutanol retrofit for Butamax, a company formed in 2003 to search for petroleum substitutes.

One other company in the country, Gevo Inc., is attempting to scale up isobutanol production to a commercial level; Gevo opened up a retrofitted ethanol plant last year but halted isobutanol production because of a bug in the system. Gevo resumed production in June.

Only slight modifications are needed to turn an ethanol plant into an isobutanol plant, involving adding yeast that has been modified to produce isobutanol rather than ethanol. The Butamax retrofit process will also involve installing new separation technology, an important byproduct in ethanol production.

Highwater Ethanol CEO Brian Kletscher said in a statement that the company had “investigated other options for corn oil recovery” but was most impressed with Butamax’s technology. Butamax has eight ethanol companies in an “early adopters” group that have expressed interest in retrofitting facilities for isobutanol production. In all, the facilities would have a capacity of 900 million gallons.

Many critics of expanded use of ethanol, including in the boating industry, have pinned their hopes on isobutanol as their renewable fuel of choice.

Because isobutanol contains less oxygen than ethanol, higher volumes can be used without concern — 10 percent ethanol is roughly equivalent to 16.1 percent isobutanol. The isobutanol blends also pack more energy than ethanol, though both are lower than straight gasoline.

With its four-carbon structure, isobutanol also stays mixed with gasoline in the presence of water, the testing found. Ethanol, a two-carbon atom, is hygroscopic — it attracts and holds water molecules, causing it to separate from gasoline when water is added.

U.S. EPA has said that isobutanol can count for credit under the renewable fuel standard, the federal mandate that requires refiners to blend 36 billion gallons of biofuel a year into the nation’s motor fuel supply by 2022. The agency, though, has yet to complete final approval for its use in cars (Greenwire, June 14).