Effects of adsorption interferents on removal of Reactive Red 195 dye in wastewater by chitosan.

Reactive Red 195, which is an azoic anionic dye characterized by the presence of five sulfonic groups and one azoic group, is efficiently removed using chitosan. The increasing chitosan dose had a dramatic positive impact on the achieved color removal, there was approximately a linear relationship between chitosan dose and color removal of dye before color removal reach maximum. Also, the increase of dye concentration led to the increase of chitosan dosage in order to get the same color removal. 92 mg/L of chitosan dosage was sufficient to achieve complete remove of dye at initial concentration of dye at 200 mg/L. For the higher concentrations of dye, high dosages were necessary to reach complete color removal. On the other hand, the use of adsorption interferents (Fe^{2+}, Na^+, HCO_3^- and others) can be interesting, addition of ions had effect on the color removal of Reactive Red 195. Comparing with blank, addition of chemical species approximately decreased the color removal except Na^+ and combination of Fe^{2+} + HCO_3^-. However, comparing with Fe^{2+} alone and HCO_3^- alone, combination of Fe^{2+} + HCO^-_3 increased the color removal. [ABSTRACT FROM AUTHOR]