Effect of Alkali Treatment on the Structure and Properties of Natural Cellulose Fibers from Areca Cathechu Shells

Natural cellulose fibers with high cellulose and lignin content and elongation as high as 45% similar to that of coir were extracted from the shells of Areca cathechu for potential use for composite, textile and other applications. Areca shells are removed to obtain the nuts and are disposed as waste with no significant value. The shells are lignocellulosic in nature and have antioxidant properties and usefulfor medical applications. Some attempts have been made to utilize the shells as reinforcement for composites, conversion into carbon etc. In this research, we have subject areca shells to extensive alkali treatment to obtain cellulose rich fibers. Alkali treatment resulted in compositional, structural and morphological changes to the fibers depending on the concentration of alkali and treatment time. Tensile strength increased from 23 to 59 MPa and elongation from 34% to 45%. Although, there was no major change in the composition of the fibers, the diameter of the fibers decreased by about 50% and thermal stability showed substantial improvement. Morphological changes included increase in pores and surface appearance. Fibers obtained in this research show potential for composite and other applications. Using areca nut shells for fibrous applications could lead to substantial value addition and eventual use of the shells as sustainable sources for materials and products.