Production and characterization of cellulose nanoparticles from nopal waste by means of high impact milling

Apart from its dietary use, Opuntia ficus-indica (OFI), also known as nopal, is widely used in diverse non-food areas given its multiple properties and health benefits. In Mexico City, each year de-thorning process of nopal generates around 40,000 tons of waste. This waste contains a huge amount of hemicellulose and cellulose that can be used as a new biodegradable nanocomposite. Therefore, the aim of this work was to purify nopal thorns to obtain cellulose nanoparticles by high impact milling or high-energy ball milling. Confocal laser scanning microscopy (CLSM) showed that thorns have two main polysaccharides arranged in parallel fibers: cellulose and lignin. Size of the obtained cellulose nanoparticles were ranged from 24 to 122 nm. Crystallinity, as well as the type of cellulose obtained, were analyzed by means of XRD to evaluate its potential use as nanocomposite.