NARA award. NARA includes a broad consortium of scientists from universities, government laboratories and private industry. The Washington State University (WSU)-led grant aims to address the need for a domestic biofuel alternative for US commercial and military air fleets. The NARA project envisions developing a new, viable, aviation fuel industry using wood and wood waste in the Pacific Northwest, where forests cover almost half of the region.

The project also will focus on increasing the profitability of wood-based fuels through development of high-value, bio-based co-products to replace petrochemicals that are used in products such as plastics.

Gevo, the only product development company in this consortium, believes that woody biomass can be used as a cellulosic feedstock to create petroleum replacements such as isobutanol. In July 2010, Gevo reported the successful production of isobutanol from fermentable sugars derived from cellulosic biomass. The company also successfully converted the cellulosic isobutanol into isobutylene and paraffinic kerosene (jet fuel).(Earlier post.)

Gevo uses synthetic biology and metabolic engineering to develop biocatalysts (fermentation organisms) to make only isobutanol via fermentation at high concentrations—i.e., without the typical expression of co-products. The initial generation biocatalyst operates on fermentable sugars from grain crops, sugar cane and sugar beets. Gevo has already produced renewable gasoline and jet fuel that meet or exceed all ASTM specifications. The company is now developing a new generation of biocatalysts that can use the mixed sugars from biomass to produce cellulosic isobutanol.

The NARA project is a critical next step in proving its effectiveness. Gevo intends to use its portion of the award to optimize its cellulosic yeast and fermentation process.

Gevo previously announced its progress to airline engine testing using starch derived isobutanol to jet fuel. Gevo expects to receive full fuel certification by 2013 from the American Society for Testing and Materials (ASTM) for its biojet fuel. (Earlier post.) Gevo also recently announced a toll-manufacturing alliance with Texas-based South Hampton Resources for the construction of a demonstration plant to make biojet fuel and other hydrocarbons from Gevo’s renewable isobutanol.

Other NARA members include Weyerhaeuser, Catchlight Energy, Oregon State University, Pennsylvania State University, and the University of Minnesota.

DLA contract. The Gevo contract is the first ATJ fuel contract awarded by the DLA. The contract stipulates that Gevo will supply the USAF with 7,000 gallons of ATJ fuel. The fuel will be shipped to Wright-Patterson Air Force Base, where the Air Force will finish lab testing and begin engine testing. DLA has the option to order up to an additional 4,000 gallons at the end of the contract.

The ATJ fuel is scheduled to be produced from isobutanol at Gevo’s hydrocarbon processing demonstration plant in Silsbee, Texas, in partnership with South Hampton Resources. The company plans to begin shipping product to the USAF in the first quarter of 2012.

Gevo ATJ. Gevo uses known chemistry and existing refinery infrastructure to convert isobutanol into aliphatic and aromatic hydrocarbons:

Bio-derived isobutanol (from starch or biomass) is dehydrated over an acidic catalyst to produce isobutylene, which is then further reacted to product mixtures of longer chain aliphatic hydrocarbons. A portion of this material is reacted separately to form high density aromatic compounds.

Hydrogen gas, a byproduct of the aromatization reaction, is used to remove unsaturated bonds in the aliphatic material.

The hydrocarbons then are blended in proportions that can meet all ASTM standards for fuels: isooctane is a dimer of dehydrated isobutanol and is a major component of the premium value alkylates, a key gasoline component; a trimer of the isobutylene (dehydrated isobutanol) is a jet fuel blend stock; a polymer of four and five isobutylenes can make a diesel blend stock.

The resulting kerosene is the same as that conventionally produced form butylenes, says Gevo CEO Patrick Gruber.