Synthesis and characterization of a novel double network hydrogel based on gellan‐gum crosslinked by octavinyl polyhedral oligomeric silsesquioxane for heavy metal removal

Abstract

In this study, we demonstrated a new design technique for producing DNNH based on gellan-gum crosslinked by octavinyl polyhedral oligomeric silsesquioxane. Incorporating OV-POSS nanoparticles as cross-linkers into the first and second networks created strong coordination contacts and improved mechanical performance with 90% water. pH and contact time affect DNNH swelling, Ni(II), and Pb(II) removal. The resulting hydrogels were characterized by FT-IR, SEM, XRD, and TGA analyzes. The capacity of the hydrogel to adsorb Ni(II) and Pb(II) is 213.66 and 132.55 mg/g, respectively, according to the adsorption isotherm model. The usefulness of kinetic and isotherm investigations, notably the pseudo-second-order model and the Langmuir model, for the adsorption of the aforementioned contaminants, was proven. Ni(II) and Pb(II) adsorption is spontaneous and endothermic, according to the study. The hydrogel's adsorption-desorption reusability was renewed five times. As a consequence, the generated hydrogel is recognized as a good adsorbent for aqueous Ni(II) and Pb(II) adsorption.

Magnetic, Biocompatible and Biodegradable Carboxymethyl Cellulose‐Based Hydrogel for Cationic Dye Adsorption

“…As can be seen, there is a high MB and CV adsorption rate during the initial 40 min of the process, followed by a slow adsorption rate. This is attributed to the higher adsorption sites on the hydrogel's surface at the beginning of the process [49,50] . At higher concentrations of MB and CV, it takes longer to reach equilibrium.…”

“…This is attributed to the higher adsorption sites on the hydrogel's surface at the beginning of the process. [49,50] At higher concentrations of MB and CV, it takes longer to reach equilibrium. Based on pseudo-first-order and pseudo-secondorder kinetic models, both models showed a good fitting (Table 2).…”