Document Type: Research Article
birjand university of medical sciences
Untreated wastewater disposal containing synthetic dyes produces serious problems in the environment. Industrial wastewater containing dye requires treatment by a suitable process before discharging into the environment. The present study has been performed as batch experimental study. Nanochitosan was synthesized from the Persian Gulf shrimp shell. The effect of the various parameters including pH, initial concentration of the RB29 dye, the equation contact time, and the adsorbent dosage as well as isotherm, thermodynamic and kinetic of the adsorption process were evaluated. The results of this study demonstrated that the maximum adsorption capacity of the nanochitosan, which occurred in pH=4, adsorbent dosage of 0.2 g/L, the concentration of 50 mg/L of RB29 dye and during 90 minutes, was 113.22 mg/g. Temkin and Dubinin-Radushkeish isotherms and pseudo second order kinetic equations have shown better results for describing the adsorption process. The entropic changes (ΔS°) and enthalpy changes (ΔH°) were 36.65J/mole K and 6.43 kJ/mole respectively. Also the Gibbs free energy (ΔG) was negative. Therefore nanochitosan can be used as a suitable low cost adsorbent for removal of RB29 dye from aqueous solutions.