Peruvian Starch-Based Magnetic Hydrogel for Crystal Violet Dye Removal in Aqueous Media

Alviz-Meza A.; Carranza-Oropeza M.V.; Huaccallo-Aguilar Y.; Álvarez-Torrellas S.; Garcia-Rodriguez J. · Proceedings - 2025 IEEE Latin American Conference on Nanotechnology, LANANO 2025 (2025) · DOI: 10.1109/lanano68466.2025.11512537

Resumen

This study deals with the synthesis and performance of a magnetic hydrogel prepared from the starch of the native Amarilla Reyna Peruvian potato. The hydrogel was successfully synthesized by grafting polyacrylic acid onto starch, followed by crosslinking with N, N'-methylenebisacrylamide and a further in situ magnetization with iron oxides. The performed characterization of the material involved FTIR, SEM-EDS, and Hg intrusion porosimetry techniques. Also, the hydrogel was tested in the Crystal Violet (CV) dye removal from aqueous solution by adsorption, assessing kinetic, equilibrium, and thermodynamic studies. From the equilibrium adsorption studies of CV, an outstanding equilibrium adsorption capacity (qe) value of 1000 mg g-1 was obtained. The experimental data of CV adsorption best fit the pseudo-first-order kinetic model and the Langmuir adsorption model, for kinetic and equilibrium studies, respectively. Thermodynamics revealed an exothermic and spontaneous process driven by an electrostatic physisorption mechanism. The hydrogel achieved over 88% CV removal efficiency across five consecutive adsorption cycles, indicating stability and straightforward magnetic recovery of the synthesized material. These results suggested that this biodegradable, affordable hydrogel can be an effective alternative for removing cationic dyes from water.

Instituciones: Universidad Nacional Mayor de San Marcos