Sweating alcohol from carbon dioxide
Cyano Biofuels does commercial manufacture of algae based biofuel
When the US company Algenol first knocked on the doors of Cyano Biotech with a proposal for the commercial manufacture of algae based biofuel, Dan Kramer found the idea to be “absurd”. Today, the molecular biologist is building an (algae) greenhouse that is to simulate field production. Florida is witnessing a joint project with Algenol for a 16 hectare trial area. Besides carbon dioxide and sunlight, also an organism is absolutely essential for this production, an organism that had already played a crucial role in changing the conditions for life on Earth about three billion years ago: cyanobacteria, better known as blue algae.
Then as today these tiny bacteria utilise sunlight for photosynthesis and emit oxygen as a waste product. This mass production of oxygen cranked up the chemical conversion of the Earth’s oxygen free shroud into an oxygen rich atmosphere needed for the development of life outside of water. Today, blue algae could change fundamentally the highly criticised production of fuel from biomass.
How? Through ethanol synthesis, explained Dan Kramer, Managing Director of Cyano Biofuels GmbH. This already takes place in the bacteria as a completely natural process with an alcohol forming enzyme. Kramer and his colleagues have supplemented this bacteria with another enzyme, pyruvate desoxycarbolase, from the Zymomonas mobilis bacteria, also used in the production of tequila – that boosts the natural process of ethanol synthesis. In so called bioreactors – in this case hoses – blue algae are “fed” carbon dioxide in highly concentrated salt water. Up to 570 liters of ethanol are cultured out of one tonne of carbon dioxide. Under the action of sunlight the algae synthesise alcohol and “sweat” it out. Condensing on the walls of the bioreactor, the ethanol is collected and finally concentrated.
Kramer expects the new biofuel to enter economical production in three to five years, equivalent to at least four litres of fuel per square metre and year. And, Kramer added, there are many other advantages. Compared with oil based fuels, the CO2 footprint is about 80% less, according to studies by an American university. Even when compared with more sustainable production methods, e.g. with sugar cane, cellulose, or algal oil, the direct synthesis in cyanobacteria achieves far better results. The most common production method today with sugar cane returns about 750 litres per thousand square metres per year after two harvests. The present values obtained with the cyano method indicate a yield at least ten times this amount – and that, added Kramer, without the consumption of natural resources and foods and without the exploitation of agricultural land. And that, at the same time, an enormous amount of carbon dioxide “disappears” will also benefit the atmosphere, which the bacteria were once so busy in creating.
by Rico Bigelmann
Link: www.cyano-biofuels.com