Scientists at a UK university have developed a membrane-based extraction method which could make biofuels cost-competitive with petroleum-based transport fuels.
The Livingston Group at Imperial College London, in collaboration with bp, has developed an extraction method which is said to use less than 25% of the energy of current processes and produces ten times more biofuel with over 99.5% purity.
The research group’s findings have been published in the peer reviewed Energy & Environmental Science journal.
Lead author Professor Andrew Livingston of Imperial’s Department of Chemical Engineering commented on the new process: ‘Because they are expensive, biofuels are usually combined with petrol or diesel to make them “go further”.
‘Our new technology could help to drive down the cost of biofuels so that they eventually replace fossil fuels in transport and aviation – a much happier situation for the environment and one we are all working towards.’
Biofuels are produced by fermenting waste biomass and recovering the fuel from the fermented solution using an extractant. However, as the Imperial College research team highlighted, ‘both biofuels and extractants are toxic to the necessary microorganisms in the solution, so can inhibit production and increase energy consumption.
The researchers selected a thin-film composite membrane which blocks the transport of extractant and water, allowing only the biofuel to pass through. They found that this protected the microorganisms and enabled continuous production, resulting in a ten-fold increase in productivity compared with conventional techniques.