Synthesis and Characterization of Alginate/Bentonite Hydrogels

MORANT, MÓNICA ALEJANDRA; HORST, MARÍA FERNANDA; GIAROLI, MARÍA CAROLINA; RODRÍGUEZ, MARIO HUMBERTO; NINAGO, MARIO DANIEL

MACROMOLECULAR SYMPOSIA

WILEY

Lugar: New York; Año: 2022 vol. 406

1022-1360

The use of bentonite for organic dyes removal in the water system is aneconomical and highly efficient alternative against the usually appliedpurification methods. However, during the post-treatment stage bentoniteswells and forms highly stable colloidal suspensions, being difficult toseparate from the aqueous system. In this work, calcium alginate hydrogelsbeads with 5 and 10% w/w of bentonite are synthetized and their capacity toadsorb methylene blue, as model dye, from aqueous media is evaluated.Structure and mechanical properties of hydrogels beads are determined,showing that hydrogels beads with bentonite present higher viscosity andhardness. Regarding methylene blue adsorption capacity, the effect thecontact time (0–32 h) and the initial cadmium ion concentration (0.2–3.0mg L−1 ) are studied employing hydrogel beads. The equilibrium adsorptiontime is reached at 300 min for all studied hydrogels and experimental data arefitted well with a pseudo-second order kinetic model. As conclusion,alginate/bentonite hydrogel beads are accepted as a promising candidate toremove methylene blue dye from aqueous solutions.