Fabrication of eco-friendly Chitosan/Polypyrrole composite for the removal of Anionic dye from wastewater: Optimization and Modeling studies

A hetero-structured composite with remarkable adsorption performance has drawn more attention owing to its splendid performance in environmental applications. The porosity, stability, and specific surface area of Chitosan can be improved by customizing it with the appropriate bio-polymeric adsorbents, which can also exhibit strong adsorption potential. In the Present study, Chitosan (host) was fabricated via in-situ chemical oxidative polymerization strategy in different ratio. The performance of synthesized composites was tested for the adsorption of Tartrazine dye in a batch mode. Results showed a maximum adsorption efficiency of 99.02 +/- 1.980% for CS/Ppy-1:1 and 96.70 +/- 1.934% for CS/Ppy-1:2 for the removal of Tartrazine dye under an optimum condition (Initial concentration that is 100 mg/L (CS/Ppy-1:1) and 75 mg/L (CS/Ppy-1:2), pH = 5, Temperature = 25 C-degrees, Adsorbent dose = 10 mg). The adsorption isotherm and kinetic fitted well with the Langmuir model and pseudo-second-order respectively. The thermodynamic study revealed that the adsorption of dye is a spontaneous process. Further, Regeneration investigations showed over 65 +/- 0.142% regeneration efficiency with 0.1 M NaOH solution, confirming that the desorption was impeccable. The electrostatic force of interaction, hydrogen bonding, surface complexation, and pi - pi stacking interactions were all implicated in the dye adsorption mechanism on the CS/Ppy composite. Also, the proposed system treats one of the most complex azo dyes using the efficient binary composite and shows successful regeneration/recyclability of adsorbent upto four successive cycles making it a potential adsorbent for large scale upgradation.(GRAPHICS)