A New Spin On Nanocellulose

Scientists in Switzerland have developed an approach for producing cellulose nanofibers starting from vegetable food waste such as pomace left over from carrot juice production. But along the way, the team led by Roland Hischier of the Swiss Federal Laboratories for Materials Science & Technology (Empa) performed a life-cycle assessment to compare environmental impact, performance, and economic data against those for other nanocellulose preparation methods. The assessment helped the team select the processes in the new method to ensure it will be commercially competitive (ACS Sustainable Chem. Eng. 2015, DOI: 10.1021/acssuschemeng.5b00209). Cellulose nanofibers are biodegradable materials derived from renewable resources such as cotton, coconuts, and wood pulp that are being developed as alternatives to carbon or glass fibers for food packaging, medical applications, and organic-based displays. Because nanocellulose is only just beginning to be commercialized, the production methods are still being worked out. Hischier and his colleagues looked at energy use, choice of starting material, water and solvent use, and waste trade-offs. They selected enzymes over chemical acid hydrolysis to depolymerize and isolate the cellulose, identified an approach to functionalize the fiber surface with a polymer coating, and chose a wet-spinning method over commonly used electrospinning to orient the fibers and spin them into yarn. The team also looked at other details, such as whether carrot pomace was best burned for energy production, used as a fertilizer, or as a source of nanocellulose.