Nanocellulose from citrus processing waste using water and electricity only
Abstract Along with a water-soluble fraction rich in pectin, the hydrodynamic cavitation of citrus processing waste carried out in water directly on a semi-industrial scale affords an insoluble fraction consisting of a new nanocellulose of high quality. Lemon and grapefruit nanocellulose powders isolated upon filtration and mild drying consist, respectively, of 100-500 nm wide cellulose nanorods, and of 500-1,000 nm wide ramified microfibrils extending for several μm. The process is general and can be applied to any citrus processing biowaste. These findings establish a long-sought technically viable route to a material whose numerous potential applications in fields ranging from biomedicine to composite production have been limited by the harsh conditions required for the extraction of nanocellulose via acid or enzymatic hydrolysis following pretreatment of lignocellulosic biomass with acid-chlorite or alkali.
