Cellulosic Biobutanol from Wheat Straw
25 June 2007
Scientists at the USDA Agricultural Research Services (USDA ARS) are exploring the production of cellulosic biobutanol from wheat straw using Clostridium Beijerinckii. The research is part of a larger, ongoing research project: Cost-Effective Bioprocess Technologies for Production of Biofuels from Lignocellulosic Biomass.
In work to be published in the Journal of Biotechnology, Nasib Qureshi, Badal Saha and Michael Cotta achieved a rate of production of wheat straw hydrolysate to butanol of 214% over that from glucose.
Wheat straw contains about 70% complex carbohydrate that can serve as a low cost feedstock for conversion to fuel ethanol.
Clostridium beijerinckii P260 can utilize five and six carbon sugars present in cellulosic biomass and convert them to butanol. The researchers pretreated wheat straw with dilute sulfuric acid and hydrolyzed it using commercial carbohydrases to lignocellulosic component sugars (glucose, xylose, arabinose, galactose, and mannose) prior to their conversion to butanol.
Hydrolysis, fermentation, and product recovery were combined in a single step using a 2.5-liter bioreactor. Fermentation performance was enhanced by simultaneously recovering products [Acetone-butanol (AB)] from the fermentation broth by gas stripping, thereby avoiding inhibition of the end product.
The reactor operated in a fed-batch mode, and fermentation lasted for more than 500 hours.
Resources:
Qureshi, N., Saha, B.C., Cotta, M.A. 2007. “Bioconversion of wheat straw to butanol (a superior liquid fuel): simultaneous saccharification, fermentation, and product recovery” [abstract]. Biotechnology for Fuels and Chemicals. Paper No. 4-16.
So...what are the implications of increasing biobutanol production 214%? Does this allow production at between $1-2.00/gallon?
What is the annual production potential from wheat straw as a feedstock?
Posted by: HealthyBreeze | 25 June 2007 at 02:46 PM
It took 21 days to make one batch. That's not economic.
Posted by: Steven | 25 June 2007 at 03:49 PM
No, it's "fed-batch" mode, meaning new reactants are introduced as products are removed. It would be interesting to know the total amount of product produced in 500 hours.
Posted by: BlackSun | 25 June 2007 at 03:58 PM
Since it uses 'waste' instead of grains, it's a step in the right direction. I'd like to know what the EROEI is.
Posted by: PeakVT | 25 June 2007 at 04:56 PM
Hmm. Butanol can transport through pipelines like oil can, while ethanol can't.
From the overall info I've seen, butanol seems far superior to ethanol. Butanol is less water soluble, has a higher energy content. If I remember correctly, you could put butanol in your regular ICE and not have any problems, where as if you wanted to use ethanol, you need a flex fuel car.
Butanol will probably get overlooked though. It's much more attractive to politicians to give welfare handouts to corn growers and then use the power of taxation to artificially make ethanol fuel reasonably priced.
Posted by: DB | 25 June 2007 at 09:25 PM
BioButanol isn't as far along as ethanol, and has biproducts like acetone, that may not be needed. We've been making booze longer than we've been making biofuel. Dupont seems to be betting heavily on BioButanol, and it's good to see them forming alliances with BP for viability.
I wonder how hard it will be in a couple years to convert the hundreds of corn ethanol plants (that are being built for tax dodge purposes) to biobutanol.
If we were going to do a Manhattan project for biomass, biobutanol is a strong contender for what we should be focusing on.
Posted by: HealthyBreeze | 26 June 2007 at 10:28 AM
The large scale Manhatten approach needs to apply to a diversity of solutions not just butanol or EVs. The approach is lots of teams each specializing in one or another renewable. H2 cannot be ruled out as an energy carrier once efficient production methods are developed.
As for biomass - cellulosic is the long term solution, corn merely transitional. And not far enough along is algal oil grown in salt water.
Posted by: gr | 26 June 2007 at 11:22 AM
We use a lot of fossil fuel from foreign sources now, and therefore like in the game of Monopoly, we will end up selling everything to them with the gas stations.
Hybrids, electric hybrids, lithium ion battery powered hybrids with plug in capability with end our hopeless situation, so we need an Apollo Project to manufacture on our own soil PHEVs including their batteries.
While some of us need to drive a long way, the bulk of us can get by most days "burning" domestic power from the plug. Gas prices would fall once domestic supply exceeds demand.
Posted by: Van | 26 June 2007 at 11:33 PM
Even though it's made from "waste", that shouldn't deter us from thinking that prices won't go up. "Waste" with a high market demand quickly becomes a "co-product".
Posted by: Doug | 27 June 2007 at 09:55 PM
Biobutanol also doesn't have the corn lobby behind it to push its adoption. But it does have BP/DuPont and apparently Boeing & Virgin.
It didn't get the impression from this research that it was considered a success or not. I would want to know what items have been identified that may be critical to the commercialization efforts that this research has impacted. Is it just basic groundwork?
Posted by: Doug | 27 June 2007 at 10:42 PM
I think the key question is, what is the absolute yeild and cost per gallon? Increasing the yeild 214% on a small base may not deliver what the market needs.
Posted by: HealthyBreeze | 29 June 2007 at 05:28 PM
Butanol is the fuel i want to see come available at the pumps. It is transportable via the existing distribution network (a huge plus), it can be used directly in my classic car (1968 Falcon), can be used dirctly in my motorcycle (Yamaha FZR 1000), and can be used in my daily driver (2005 Pontiac Vibe). All that remains is for it to become produceable via catalytic conversion. Using fermentation even in controlled environments is difficult and expensive (so i see). I am praying that this will come to be, even though i do not see the long term implications of this path (but i know He does).
Posted by: avid a g | 30 October 2007 at 09:05 AM
I am all for giving bio-fuels like butanol support so that they can be an additional energy source to stretch oil and natural gas supplies. I am against this whole campaign to hold down supplies of fossil fuel so that alternative energy can remain competitive. The ethanol boondogle is the easiest to see. It does nothing to lower the use of petroleum and raises the cost of gasoline and food.
This IS the primary inflationary factor in the US economy.
Hopefully butanol will not become another economic black hole like ethanol, solar, and windmills are.
Posted by: Witless | 05 January 2008 at 08:51 AM