Renewable energy branches out
4 Dec 2017 by Evoluted New Media
A team from the US have found a way to convert one of the World’s most abundant polymer – lignin –into a renewable biomass source.
A team from the US have found a way to convert one of the World’s most abundant polymer – lignin –into a renewable biomass source.
Lignin is found in every plant, making up wood, stems and cell walls and if it can be chemically converted into biofuels, it would provide a huge boost in renewable energy. The components of lignin can also have a range of other applications in industries such as pharmaceuticals and plastics. Currently there are two ways it is processed, either with high heat in the absence of oxygen or in acid with high heat. However, the resulting products are often unstable and reactive and easily re-polymerise.
Igor Slowing, from the US Department of Energy (DOE) and co-author of the study published in Journal of Materials Chemistry A, said: “It’s kind of a horrible mess, really. We need to be able to deconstruct lignin in a way that is economically feasible and into stable, readily useful components.”
With other scientists at the Ames Laboratory at the DOE, Slowing experimented on a number of chemical reactions that decompose lignin models at low temperatures and pressures. Although there are methods to salvage byproducts via a stabilisation process, the researchers combined the decomposition and stabilisation process using a phosphate modified cerium (IV) oxide (ceria).
Slowing said: “Our process does the breaking of lignin-like material and the stabilisation in a single step in very mild conditions. The interesting thing is that though there are two different types of chemical processes happening in a single material, they appear to be working synergistically, and are able to do that at a lower temperature."
In a separate experiment, Slowing and his team processed a related material, phenol, into useful precursors for nylon production. This involved using a catalyst made of ceria and palladium doped with sodium, significantly increasing the reactivity. Additionally, the researchers eliminated the use of hydrogen, produced from the steam-treatment of natural gas, using an energy-conserving alcohol-based hydrogenation process instead.
Slowing added: “Both of these results were very promising, and our next step is to combine the two experiments into one, and achieve lignin deconstruction using hydrogen from a renewable source."
