Adsorption, Kinetics and Thermodynamics of Reactive Dyes on Chitosan Treated Cotton Fabric

Abstract

The adsorption performance, kinetics, and thermodynamic parameters of reactive dyes on chitosan-treated cotton fabric are described in this research. The batch experiment was carried out to investigate the influence of pH, time, temperature, dye concentration, and material to liquid ratio of Remazol Red RR and Remazol Yellow RR, two widely used reactive dyes. The adsorption of red and yellow dyes was observed at λmax 517 and 419 nm respectively. For both Remazol Red RR and Remazol Yellow RR reactive dyes with starting dye concentrations of 0.0667 and 40 mg/L, the greatest dye adsorption was reported at pH 11 (0.0009 and 0.1284 mg/g) and pH 4 (0.0004 and 0.1038 mg/g). The adsorption performance was investigated using the Langmuir and Freundlich isotherms. The adsorption behaviours of the two reactive dyes closely matched to the Langmuir adsorption isotherm (R2>0.98) than Freundlich isotherm (R2>0.92). The pseudo-second-order kinetic model (R2>0.99) was followed by the dyeing kinetics of modified cotton sample. Thermodynamic investigation was covered with enthalpy change (ΔH⁰), Gibbs free energy (ΔG⁰) and entropy change (ΔS⁰) where all the values were reported positive confirming that the adsorption process was non-spontaneous, endothermic and the higher affinity of reactive dye on chitosan treated cotton.

Grafting of cotton fabrics with diallyldimethylammonium chloride

“…This result may be explained by the fact that the anionic reactive dyes were successfully adsorbed onto the treated substrates by the ionic interaction in the modi ed cotton with the cationic monomer (DADMAC), which supplied cationic sites (-N + R4 groups) onto the substrate. The anionic reactive dye was adsorbed at the active sites, which were the quaternary ammonium groups (cationic groups) (Roy et al 2023). It can be seen from the results that the modi ed cotton fabrics showed saturation adsorption at 8.53 mg/g, 10.5 mg/g, and 11.89 mg/g for RB 171, RR 195, and RY 184, respectively.…”

Functionalization of Technical Textiles with Chitosan

“…The stainability of the chitosan-functionalized fabrics is attributed to the presence of primary amino groups in chitosan, which can form covalent bonds with reactive dyes, or build electrostatic interactions with the dye anions in their protonated form (NH3) + [33]. Several experiments have been previously reported using reactive red dyes to stain chitosan-functionalized textiles, but using more intense reaction conditions with temperatures between 40 and 60 °C and reaction times of 30-160 min [25,34,35], showing similar effects. The conditions used here with a mild dyeing temperature of 50 °C and a very short reaction time of 5 min have The results show that staining with Remazol Brillant Red F3B is suitable for use in the detection of chitosan on both CO/PES mixed and pure PES textiles: chitosan-functionalized samples were stained, whereas the references were not.…”