Bio-adsorption of methylene blue dye using chitosan-extracted from Fenneropenaeus indicus shrimp shell waste

Abstract

The cationic dye “Methylene blue” is widely used in textiles industry, pharmaceuticals, paper industries, and ink manufacturing etc, The washed off dyes discharged directly in water bodies and cause major damage to the environment. The molecule of dye is very stable, so that it is very difficult to decompose naturally. Therefore, it is essential to remove the dye by purifying, and prevent the environment from pollution. The –NH2 and -OH functional groups of Chitosan can induce the adsorbing capacity of dyes by its low surface area, porosity and high crystalline nature. Chitosan is an environment friendly, non-toxic, easily available, biodegradable, renewable biopolymer, and harmless to biota. Extraction of chitosan from the “Fenneropenaeus indicus” (Shrimp) shell and its utilization in wastewater treatment controls the environmental problems and contributes to solid waste management. In this study, the possible use of “Fenneropenaeus indicus” (Shrimp) shell chitosan for the bio-adsorption of MB dye was investigated by a batch adsorption method using different adsorbent doses with respect to experimental duration. The maximum amount of dye adsorption was obtained at a minimum dose of 4gram chitosan, with experimental time of 4 hours. The Fenneropenaeus indicus shell chitosan was found to be a better adsorbent since it removes about 93.23% of methylene blue dye from sample water. Further, characterization of functional groups was also done and the changes of groups were observed from both control and treated samples.