Graphitic C3N4 incorporated chitosan-poly(vinyl alcohol) blend nanocomposites for the removal of Cu(II) and Cr(VI) ions from aqueous solutions

A novel adsorbent material for the effective removal of hazardous metal ions from aqueous solutions was developed through modifications to chitosan. The process involved the use of vanillin to create cross-linked chitosan, which was then combined with thiourea-based graphitic carbon nitride (g-C3N4) to form a gel matrix. The resulting composite material was thoroughly characterized using various techniques, including Fourier transform infrared spectroscopy, thermogravimetric analysis, scanning electron microscopy, energy dispersive X-ray spectroscopy, and X-ray diffractometry. To assess its efficacy, adsorption experiments were conducted to determine the capability of the synthesized compounds to adsorb Cu(II) and Cr(VI) ions. The observed results found that the adsorption process was found to follow pseudo-second-order kinetics and the Langmuir isotherm model. Through thermodynamic studies, it was revealed that the adsorption process was both endothermic and spontaneous in nature. Furthermore, desorption studies confirmed that the material could be regenerated, making it reusable. This characteristic allowed for the effective recovery of the adsorbate species and highlighted the potential for reusing the adsorbent material multiple times.