Soon beer may be able to fuel you as well your car
Chemists at the University of Bristol have devised a method to turn alcohol into butanol which could be used to run vehicles.
Butanol is a good alternative to petrol but synthesizing it from sustainable sources is difficult. Bio-ethanol (or commonly known as bio-fuel when sold mixed with petrol), though, is one of the most widely known alternate fuel, but this is not an ideal replacement. It has issues such as lower energy density, it mixes too easily with water and can be fairly corrosive to engines.
The scientists who have been working on the project for years have already demonstrated the conversion in laboratory conditions with pure, dry ethanol. But, if this technology is to be scaled up, it needs to work with real ethanol fermentation broths. These broths contain a lot of water (about 90 percent) and other impurities, so the new technology has to be developed to tolerate that.
"The alcohol in alcoholic drinks is actually ethanol - exactly the same molecule that we want to convert into butanol as a petrol replacement. So alcoholic drinks are an ideal model for industrial ethanol fermentation broths - ethanol for fuel is essentially made using a brewing process,” said Professor Duncan Wass.
"If our technology works with alcoholic drinks (especially beer which is the best model) then it shows it has the potential to be scaled up to make butanol as a petrol replacement on an industrial scale."
A laboratory setup demonstrating the conversion. Source: University of Bristol
A catalyst— chemicals which can speed up and control a chemical reaction—was used to convert ethanol into butanol. This catalyst is the key finding of the team from the University. In demonstrating that catalysts work with a ‘real’ ethanol mixture, the team has demonstrated a key step in scaling this technology up to industrial application.
"We wouldn’t actually want to use beer on an industrial scale and compete with potential food crops. But there are ways to obtain ethanol for fuel from fermentation that produce something that chemically is very much like beer - so beer is an excellent readily available model to test our technology," Professor Wass added.
The next step in terms of application is to build this into a large scale process and, based on previous processes, this could take as long as five years even if everything went well. From a scientific point of view, the team is now trying to understand what makes their catalysts so successful."Turning beer into petrol was a bit of fun, and something to do with the leftovers of the lab Christmas party, but it has a serious point. Beer is actually an excellent model for the mixture of chemicals we would need to use in a real industrial process, so it shows this technology is one step closer to reality," Professor Wass said.