Waste is worth its weight in gold

Lignin, a waste product of the pulp and paper industry that is overlooked in the production of biofuels, could turn out to be a key ingredient. How? Scientists have found a solution.

In order to reduce our dependence on fossil fuels, we must turn to biofuels (produced from plants) and chemical compounds. However, the cost-effective production of 'green' fuel from biomass is quite a challenge for scientists today. Most biomass comes from non-edible plants like trees, grass and algae, which contain sugars that can be fermented to produce fuel.

However, biomass also contains lignin, an organic polymer that is a component of wood (more specifically, bark), giving it stiffness. Because it is difficult to process, it is usually omitted from biofuel production. 

Researchers at the Federal Polytechnic University of Lausanne have succeeded in turning a troublesome polymer into an invaluable component of biofuels. They achieved this by combining it with a common chemical compound to break it down into useful molecules in 80%.

Lignin is an extremely complex polymer, filling every free space in plant cells. In principle, it can be assumed that biomass is predominantly made up of lignin, and its molecular structure allows for a 30% higher energy density compared to that obtained from sugars, traditionally used in biofuel production.

The main problem is the extraction of lignin and its transformation. Due to its instability, lignin is usually quickly destroyed during extraction attempts and many scientists have not been able to split it and use it as a component in the production of fuels and chemical compounds.

That was until. An international team of scientists, led by Jeremi Luterbacher of the Federal Polytechnic University of Lausanne, has proved that they can easily do what researchers from all over the world have been breaking their heads over. In the process, they are using formaldehyde, one of the most widely used chemical compounds and, in addition, also one of the cheapest to produce.

Formaldehyde was found to stabilise lignin and prevent its degradation, thus providing the possibility of using it in the production of substitutes in the petrochemical industry. This gave results up to seven times better than when lignin without formaldehyde was used in the same process.

Elaborated based on www.phys.org