New membrane could pave way for cheap, efficiently made biofuels

In the United Kingdom, Livingston Group at Imperial College London in collaboration with bp developed a membrane-based extraction system which uses less than 25 percent of the energy of current processes and produces ten times more biofuel with over 99.5 percent purity.

In their labs at Imperial, researchers investigated the performance of several thin-film composite membranes and settled on one which can block the transport of extractant and water, allowing only the biofuel to travel through. They found that this protected the microorganisms and enabled continuous production, resulting in a ten-fold increase in productivity compared with conventional techniques.

They tested the membrane with three different extractant solvents to further fine-tune the best operating conditions. They found that the 2-ethyl-1-hexanol extractant exhibited a five times faster recovery rate, which reduced the energy consumption of the process to less than one quarter of conventional recovery systems.

Lead author Professor Andrew Livingston of Imperial’s Department of Chemical Engineering said: “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.”