Extraction and Characterisation of Cellulose Nanocrystals Structures from Waste Office Paper

Abstract

The increase of consumption of paper has led to environmental issues due to the landfill and incineration activities. Subsequently, one of the major cellulosic waste materials includes thewaste office paper (WOP). This wastage undergoes a value-added process, which is by having it converted into cellulose nanocrystals (CNC) that is prepared byanenvironmentally friendly and cost-effective method. Hence, this study is performed to synthesise CNC from WOP by acid hydrolysis method with the optimum acid concentrationchosenbased on the selected parameters. Until present time,limited research has been carried outon the preparation of CNC from WOP. Furthermore, the process ofpreparing CNC from WOP is easier andit is more energy and time efficient due to the minimumamount of lignin,compared to other cellulosic wastes. The alkali pretreatment and acid hydrolysis methodswere conducted before further analysis by using X-ray Diffraction (XRD) in order to establish the crystallinity index (CrI) and Fourier-transform infrared (FTIR) spectroscopy, which show the confirmation of non-cellulosic materials that has been removed by alkali treatment with the 5 wt %concentration. In addition, via the Scanning Electron Microscopy (SEM), it was found that the surface morphology of the alkali-treated WOP was smoother than the untreatedones. From the result obtained, the optimum acid concentration is 30 wt %,with 90 minutes of hydrolysis time and 45°C temperature with the highest CrI and crystallite size of 36.35% and 32.92 nm, respectively. The extraction of CNC from WOP provides possible applicationas reinforcement in the nanocomposite industry. Thus, the use of WOP can be considered as green material, where it alignswith the sustainable design and development.