Making the Grade

Isobutanol cleared by EPA
By Susanne Retka Schill | January 17, 2011

Gevo Inc. announced its isobutanol has successfully been registered with the U.S. EPA as a fuel additive. Under the renewable fuel standard, isobutanol now qualifies for 30 percent more renewable fuel value, or renewable identification numbers (RINs) than ethanol for obligated parties.

Gevo will soon begin the retrofit of the 22 MMgy corn ethanol plant in Luverne, Minn., to produce 18 MMgy of isobutanol, expected to be online in 2012. It entered a quiet period in mid-August after filing a registration with U.S. Securities and Exchange commission related to its initial public offering. The company will integrate a proprietary fermentation process that's designed to fit into existing ethanol production plants. Coined GIFT (Gevo Integration Fermentation Technology), the technology platform consists of two components: a yeast biocatalyst and a separations technology unit that bolts onto existing ethanol plants to produce isobutanol from grain crops such as corn, wheat, sorghum, barley and sugarcane, as well as nonfood-based cellulosic inputs.

With a higher energy density than ethanol and lower Reid Vapor Pressure, Gevo believes isobutanol will be an attractive blendstock. "We’ve taken another important step in commercializing our product in the near term, said Gevo CEO Patrick Gruber. "Along with the chemicals market, selling isobutanol as a low Reid Vapor Pressure biofuel blendstock is one of our most important opportunities."  Gevo’s isobutanol can be used directly as a specialty chemical, as a gasoline and jet fuel blendstock, and through conversion into plastics, fibers, rubber and other polymers.