Investigation of removal efficiency of Cr (VI) from industrial wastewater using chitosan and synthesized chitosan nanoparticles

Chromium (VI) is present in the effluents from different industries which maycause serious environmental problems. The aim of this study was to synthesis ofchitosan nanoparticles and their comparison with chitosan for removal of Cr (VI)ions from industrial waste water. The Synthesizing of the nanoparticle adsorbentswas successfully done by the crosslinking method. The nanoparticles sizes weredetermined between the ranges of 50-100 nm. The effect of the pH solution,adsorbents dosage, initial concentration of chromium ion and contact timefor the absorption of Cr (VI) were investigated by means of atomic absorptionspectroscopy. Maximum adsorption of chitosan nanoparticles and chitosan were44 & 16 mg/g, respectively (p <0.001). The optimum conditions for removal ofCr (VI) were determined to be pH=5 for nanochitosan solution, 1gr/L of theinitial concentration of metal ion, adsorbents dosage of 0.125 g/L and the3-hour contact time. The results showed that nanochitosan possesses a higherabsorption capacity for Cr (VI) compared to the chitosan, which related to theincrease in the nanochitosan effective surface.