Effective removal of metal ions using MoS₂ functionalized chitosan Schiff base incorporated with C₃N₄ nanoparticle from aqueous solutions

In the present work, a novel pyrazole-based chitosan Schiff base material was prepared using 5-(4-Methoxyphenoxy)-3-methyl-1-phenyl-1H-pyrazol-4-carboxaldehyde and was modified using MoS₂-C₃N₄, where the nanoparticles get embedded within the polymeric matrix. Further composite material was analyzed and characterized using various analytical techniques such as XRD, SEM, FTIR, EDS, BET and TGA. The adsorbent material was analyzed for the adsorptive take-up process with a metal ion concentration ranging from 20 to 100 mgL⁻¹ and the adsorption occurred due to the interaction between the metal ions and the chitosan Schiff base. The maximum adsorption capacity obtained for the material was 333.3 and 200.02 mg/g for Cu(II) and Cr(VI) respectively. The adsorptive mechanism was found to possess pseudo-second-order kinetics and with a Langmuir adsorption isothermal fit following the monolayer accumulation process. Further, the evaluated thermodynamic study was evaluated to check the thermodynamic parameters which showed the adsorption phenomenon to be spontaneous and showed endothermicity in nature. A regeneration and reusability study was achieved for the composite material using convenient stripping solutions.