Characterization of decrystallized chitosan and its application in biosorption of textile dyes.

Decrystallized chitosan was produced from shrimp shells with a low degree of crystallinity (10%) and a high anionic dye binding capacity. Raw, mixed dye wastewater from a textile factory was efficiently decolorized using decrystallized chitosan that was more efficient than using normal chitosan and activated carbon. Decolorization reached 90% within 10 min and could be carried out from pH 4.5 to 8.1. Decrystallized chitosan can be regenerated by 2 M H2SO4 and was reusable more than 10 times. It is, therefore, an attractive candidate for the removal of dyes from textile wastewater.