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

Manindra Nath Roy , Md. Tofazzal Hossain, Md. Zahid Hasan , Khairul Islam, Md. Rokonuzzaman, Md. Azharul Islam , Shahjalal Khandaker , M Mahbubul Bashar

Article
2023 / Volume 6 / Pages 211-232
Received 23 March 2023; Accepted 04 May 2023; Published 15 May 2023
https://doi.org/10.31881/TLR.2023.030

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.

Keywords
reactive dye, chitosan, surface modification, cotton fibre, adsorption isotherm, dyeing kinetics, thermodynamic properties