Synthesis of Industrial Raw Material from Cellulosic Agricultural Wastes: Focus on Carboxymethyl Cellulose

Abstract

Agricultural wastes such as sugarcane bagasses, maize cob, palm kernel cake, palm oil empty fruit bunches, banana pseudo stem and orange mesocarp have been known to be potential sources of cellulose. From these cellulose sources sodium carboxymethylcellulose (NaCMC), a water soluble cellulose derivative and an essential raw material in the food, cosmetic, pharmaceutical and detergent industries could be synthesized. Importantly, orange mesocarp generated from orange peel is an abundant agricultural by-product which consists of about 62.5% cellulose. It is significantly considered as one of the alternative secondary resources for cellulose. In this work, cellulose was extracted from orange mesocarp and then converted to NaCMC. The orange mesocarp was dried and ground to pass 20 mesh screen. Cellulose was extracted using 8% NaOH at 100oC for 3.5 hrs and bleached using 3.85% NaOCl at 30oC for 3 hrs. Carboxymethylcellulose (CMC) was consequently synthesized from the extracted cellulose by alkalization followed by etherification. The physicochemical properties of the NaCMC were determined in terms of the degree of substitution, viscosity and with the use of FTIR spectroscopy. The NaCMC resulted from this work has a viscosity of 14.0cP at 29.8oC and DS 1.02 and therefore was categorized as technical grade with medium viscosity. After optimization and scaling up of the production process the NaCMC synthesized will be a useful and cheap raw material for the industries. K eywords: Agricultural wastes, industrial raw material, orange mesocarp, sodium carboxymethylcellulose.