Renewable raw materials are assuming ever-growing importance for chemical makers. New commercial-scale projects, advances in processing of second generation feedstocks and novel catalyst development exemplify efforts to extend the role of renewables.
For instance, bio-based ethanol is advancing on several fronts.
Vivergo Fuels, Hull, U.K. — a joint venture formed in 2007 by AB Sugar, Peterborough, U.K. (45%), BP, London (45%), and DuPont, Wilmington, Del. (10%) — has spent 6 years and £350 million ($550 million) to create a "biorefinery of the future." Full production — 420 million L/yr (110 million gal/yr) of bioethanol and 500,000 t/yr of animal feed — is imminent at the plant in Hull (Figure 1).
At its rated output, the plant will deliver about one third of the U.K.'s forecast demand for biofuel for gasoline. Under the European Union's Renewable Energy Directive, the U.K. government is aiming to have renewable sources account for 10% of the amount of energy used in transport by 2020, more than doubling the current 4% level.
The plant mills locally sourced feed-grade wheat into wholemeal flour. This is converted into a slurry and then treated with enzymes to break down its starch into fermentable sugars. Next, yeast converts the sugars into alcohol. The resulting beer contains 12% ethanol and goes to a distillation tower, which provides a 96%-ethanol product. Dehydration increases this concentration to 99.7%, producing fuel-grade ethanol that can be blended at around 5% in gasoline.
Evaporation concentrates the wheat protein and fiber residue, which then are dehydrated to create dried distillers grains with solubles and wet distillers grain, which are suitable for animal feed.
DuPont is building a biorefinery of its own, too. It has just broken ground in Nevada, Iowa, for a commercial-scale plant to use corn stover, an agricultural waste, to produce ethanol ("Biorefinery Beckons"). The 30-million-gal/yr unit should go onstream in 2014.
Meanwhile, BP Biofuels, Tampa, Fla., has begun a $350-million expansion of its sugar-cane-based ethanol plant at Tropical, Edeia, Brazil. The project, which includes the building of a new sugar cane mill, will double current cane-processing capacity to 5 million t/yr. When fully operational late in 2014 or early 2015, the expanded plant will be able to produce 450 million L/yr of ethanol. It also will be able to export an estimated 340 GWh/yr of electricity to the Brazilian national grid.
"Since we started operating in May 2011, we have been improving our operational efficiency and this announcement marks a further milestone in delivering our biofuels strategy," notes Mario Lindenhayn, CEO of BP Biofuels Brazil.
February saw the first commercial shipments by Amyris, Emeryville, Calif., of Biofene from its new plant in Brotas, Brazil. Biofene is the company's brand of farnesene, a long-chain hydrocarbon that can be used in a broad range of specialty chemicals such as flavors and lubricants and fuel products such as renewable diesel and jet fuel.
Amyris relies on a fermentation process in which proprietary yeast strains convert a sugar source into target molecules such as Biofene. The process can use any fermentable sugar.
"This initial shipment marks the successful completion of our startup activities. We have operated multiple tanks without contamination or surprises through several production runs during the first month of operation. We are now focused on ramping up Biofene production and delivering product to our customers, from renewable diesel for bus fleets in Brazil to squalane emollient globally and soon a range of specialty chemical applications," says John Melo, president and CEO.
Swiss specialty chemicals company Firmenich, Geneva, already has partnered with Amyris, funding technical development aimed at producing a sustainable, cost-effective and reliable source of key ingredients for the flavor and frangrance market. Japanese specialty chemicals company Kuraray, Tokyo, is using Biofene to replace petroleum-derived chemicals in the production of certain classes of high-performance polymers for the tire industry. In addition, Amyris and Total, Paris, are carrying out joint research and development into the production and marketing of renewable fuels.