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Cellulose nanofibrils (CNF) were prepared from kenaf core (KC) using acidified-chlorite bleaching method and followed by disintegration using high speed blender. The effects of disintegration time and acid treatment on the defibrillation of holocellulose were studied. Hemicellulose was found to facilitate defibrillation, as CNF without any acid treatment was fully defibrillated after 30 min. The adsorption kinetics of CNF toward cationic dye cannot be accurately determined due to its quick adsorption performance, in which the equilibrium is achieved immediately after 1 min of contact time. The effects of acid treatment on holocellulose, pH, adsorbent dosage, temperature and dye concentration were studied and optimized. Adsorption data were fitted to both Langmuir and Freundlich models where Langmuir model was found to be the better model to describe the adsorption process. Maximum adsorption capacity was found to be 122.2 mg/g at pH 9, 20 °C for the non-acid treated CNF. The CNF can be regenerated by desorption at low pH where, as much as 70 % of dye adsorbed can be desorbed after 6 cycles of adsorptiondesorption cycle.

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A highly porous cellulose nanofibril aerogel loaded with graphene oxide–iron(iii) nanocomposites was produced and used for the treatment of methylene blue in aqueous solution.

In this study, lignin has been extracted from oil palm empty fruit bunch (EFB) fibers via an organosolv process. The organosolv lignin obtained was defined by the presence of hydroxyl-containing molecules, such as guaiacyl and syringyl, and by the presence of phenolic molecules in lignin. Subsequently, the extracted organosolv lignin and graphene nanoplatelets (GNP) were utilized as filler and reinforcement in photo-curable polyurethane (PU), which is used in stereolithography 3D printing. The compatibility as well as the characteristic and structural changes of the composite were identified through the mechanical properties of the 3D-printed composites. Furthermore, the tensile strength of the composited lignin and graphene shows significant improvement as high as 27%. The hardness of the photo-curable PU composites measured by nanoindentation exhibited an enormous improvement for 0.6% of lignin-graphene at 92.49 MPa with 238% increment when compared with unmodified PU.