Development of novel cross-linked chitosan for the removal of anionic Congo red dye.

The research results summarize the potential of novel cross-linked chitosan for the removal of Congo red dye from an aqueous phase. Synthesized materials were characterized by FTIR, XRD, TGA, DSC and SEM. The effects of several process conditions like effect of adsorbent dose, contact time, initial solution pH and temperature were investigated. Equilibrium adsorption data was best fitted to Sips Isotherm model and maximum dye uptake was 1597 (mg/g) for diammonium tartrate modified chitosan (DMC) while 1447 (mg/g) for urea diammonium tartrate modified chitosan (UDMC). The adsorption kinetic data was well followed by pseudo-second-order kinetic model. The thermodynamic parameters (Gibbs energy, enthalpy and entropy) suggested the feasible and endothermic nature of Congo red adsorption over both adsorbents. The analyzed results indicated the promising ability of novel cross-linked chitosan for the removal of Congo red from aqueous phase and it can be extended to use in the treatment of textile wastewater. [ABSTRACT FROM AUTHOR]