It’s not Easy Being Clean
(February 10th, 2016) Waste doesn’t need to be burnt or burrowed – it can be turned into something useful. Portuguese scientists have discovered a way to make green detergents from agricultural and forest residues.
If you think about cleaning products, the vast majority of commercially available detergents may well be able to leave your kitchen sparkling but can be extremely dangerous for the environment: not only are they synthesised from non-renewable products but they’re also not biodegradable, with a high risk of contaminating water sources. While some progress has been made in this area to limit pollution - by replacing synthetic surfactants with biological versions - the process still has a high environmental impact when it comes to the production of vegetable oils used in their manufacture.
Now, a team from Portugal has developed a way to turn the entire operation just a little bit greener. Frederico Ferreira, based at Instituto Superior Tecnico, Cesar Fonseca, currently at Aalborg University in Denmark and PhD student Nuno Faria have created a potentially new way to synthesise these biosurfactants from lignocellulosic waste. “The idea supporting this project came from the interest in developing novel biofuels from lignocellulosic residues - agricultural, forest and municipal residues,” explain the authors.
The original concept stemmed from Faria’s PhD thesis. By focussing on the conversion of lignocellulosic sugars into glycolipids with biosurfactant properties, it soon became apparent that the process could be used towards more practical applications, like green detergents. “We consider this a two-fold green idea,” explain the authors, “since these biosurfactants are produced from renewable raw materials, such as wastes, and the molecules themselves are non-toxic and biodegradable.”
The process starts in a similar manner to the production of biofuels, such as second generation bioethanol (also known as lignocellulosic ethanol), but it takes a different turn when it gets to the bioconversion process. Instead of the common baker’s yeast to produce ethanol, this process uses Pseudozyma yeast to produce glycolipids, more specifically mannosylerythritol lipids (MEL). “At the moment, the process at laboratory scale takes approximately ten days, from biomass deconstruction, bioconversion in bioreactors and product recovery”.
Attempting to increase the versatility of their project, the team is already testing whether other raw materials can be used in the process. They’ve also established national and international partnerships to develop potential applications in other fields. The process of synthesis will need to be further refined but it’s easy to see how these glycolipids can be used in the pharmaceutical or cosmetic industry, among others.
Despite the progress, commercialisation is not exactly around the corner. “We still need to further progress on process intensification and scale-up, to reach an industrial scale; product certification for specific applications, and find the appropriate entry point in the market for the most suitable applications,” explain the authors.
For the team, the icing on the cake was when their project – Green Detergents - was announced winner of the “Green Project Awards Portugal ’15”, in the category “Research and Sustainable Development”, sponsored by Grupo Jerónimo Martins. The researchers were awarded a EUR 20,000 prize as a contribution to further technology development as well as activities to bring it closer to commercialisation. In addition, this award has allowed them to focus on disseminating their results as a way to increase social awareness about the need for a future sustainable economy.