Nanocrystalline cellulose isolated from discarded cigarette filters

We report the isolation of nanocrystalline cellulose (NCC) produced from discarded cigarette filters (DCF). The DCF were processed into cellulose via ethanolic extraction, hypochlorite bleaching, alkaline deacetylation, and then converted into NCC by sulfuric acid hydrolysis. The morphological structures of the isolated NCC established with TEM showed that the nanocrystals were needle-like with a mean length of 143 nm. FEGSEM showed the morphological transition of the micro-sized DCF to self-assembled NCC while EDX revealed the presence of Ti (as TiO2) in DCF, which was retained in the NCC. A NCC sample was freeze-dried and showed a specific surface area of 7.78 m2/g. The crystallinity of the NCC film and freeze-dried samples were 96.77% and 94.47%, respectively. Crystallite sizes of the freeze-dried (8.4 nm) and film (7.6 nm) samples correlated with the mean width (8.3 nm) of the NCC observed under TEM.