Study of the extraction of nanocellulose using deep eutectic solvent
Deep eutectic solvents (DESs) are a green alternative to acid hydrolysis in the extraction of nanocellulose. The drawbacks of acid hydrolysis method such as high toxicity, non-biodegradability and high cost of starting materials can be eliminated by using DES. These factors have motivated researchers to conduct studies to find the most effective methods of extracting nanocellulose using DESs. The aim of this research is to find the effectiveness of DES in extracting nanocellulose from corn husk and the optimal values for the range of parameters being investigated. The reason corn husk was chosen as the raw material for the extraction of nanocellulose is due to the lack of extensive research on corn husk as a raw material for nanocellulose. Corn husk is extremely easy to obtain due to it being widely grown and used hence making it an attractive candidate of raw material for nanocellulose. The effect of molar ratio of the DES composition, solid-to-solvent ratio and reaction temperature on the morphology and thermal stability of the nanocellulose will also be investigated. The corn husk will be dried and milled before being washed with distilled water to remove any water-soluble impurities. The corn husk should then be filtered and dried. With the pretreatment completed, the corn husk is then immersed in the DES under controlled parameters and allowed to react. This procedure is repeated for multiple times as the parameters are changed. The morphology and the thermal stability of the samples will be analyzed using scanning electron microscope (SEM) and thermogravimetric analysis (TGA), respectively. Under optimal conditions, the nanocellulose produced should have a diameter of approximately 5 nm and a thermal degradation temperature of approximately 350°C. The yield obtained is also expected to be in the range of 50-60%.