Izuru Kawamura and Noriko Kanai team (Kawamura laboratory, Yokohama National university,) released in April, 2020 that cellulose nanofibers were successfully derived from spent coffee grounds(SCGs). Cellulose nanofibers which are made out from cellulose in plant cell walls are five times tougher and lighter than iron, and have good insulation. It is expected that SCGs cellulose nanofibers can be used as materials and filters for buildings and as parts of cars.*
Although only 10% of cellulose can be extracted and used from spent coffee grounds to cellulose nanofibers, it is said to be a high potential material because 450,000 tons of coffee grounds are consumed every year in Japan. Most of SCGs have been wasted, but this study demonstrates that they can be used as sustainable and eco-friendly resources by collecting them properly and efficiently.
* N. Kanai, T. Honda, N. Yoshihara, T. Oyama, A. Naito, K. Ueda, I. Kawamura, “Cellulose nanofibers isolated from spent coffee grounds and their composite films with poly(vinyl alcohol): a new non-wood source” (2020) Cellulose 27, 5017-5028.