Method for preparing oxidized cellulose nanofibres from coffee grounds and nanofibres thereby obtained

Method for producing oxidized cellulose nanofibres from coffee grounds, comprising the following steps of : dispersing the coffee grounds in an aqueous solution comprising one or more of HClO, HClO2 and the salts thereof, dispersing the processed coffee grounds in an aqueous solution comprising one or more nitroxide radicals and one or more alkali salts or alkali earth salts of HBr, adding an aqueous solution comprising one or more of HC1O, HC1O2 and the salts thereof, and a base so as to maintain the pH of the dispersion in the range between 10 and 11.5, adding a strong acid until bringing the pH into the range between 1 and 3, filtering, dispersing the filtered oxidized cellulose in a basic aqueous solution at a pH between 7 and 12, defibrating the dispersed oxidized cellulose, adding to the filtered oxidized cellulose dispersion a strong acid until reaching a pH between 1 and 3, obtaining oxidized cellulose nanofibres, filtering.