Fabrication of chitosan-alginate-polyvinylpyrrolidone for efficient removal of Cr(VI) from wastewater in experiment and adsorption mechanism

This study synthesized chitosan-alginate-polyvinylpyrrolidone and applied it for Cr(VI) removal. Characterization was carried out using FTIR, TGA, N₂ adsorption, ¹H NMR, and FE-SEM. FTIR spectra show peaks at 1415 cm^− 1, 1323 cm^− 1, 1029 cm^− 1, and 448 cm^− 1, which are COO, C-N, C-O, and N-C = O groups. The surface area of CsAgPVP was 20.42 m²/g. The pore size of CsAgPVP was 5.36 nm. Field emission shows the C, O, N, and Na. The optimum conditions CsAgPVP dor adsorption Cr(VI) were 50 ppm, 360 min, and pH 4. It uses adsorption isotherm and kinetic to show the Langmuir model and pseudo-second-order. The CsAgPVP adsorption process is assumed homogeneous and considered as chemisorption. Adsorption capacity shows 208.67 mg/g. It uses a regeneration study of removal percentage up to 90% in the fourth cycle. The removal percentage in real sample mine wastewater and waste acid laboratories was 80% and 72%.