Removal of Fe (II) Ions from Aqueous Solutions Using Highly Biopolymer Nanocomposite: A Green Adsorbent Surface

Biopolymers are characterized by their three-dimensional polymeric networks, high hydrophilic properties, affordability, physical and chemical stability, non-toxicity, and exceptional ability to absorb water and other substances. In this work, the adsorption capacity of an inexpensive, biodegradable adsorbent, poly (AAC-co-AM) hydrogel, prepared by the free radical polymerization method, was studied for the removal of heavy metals such as Fe (II) ions. Several analyses of the hydrogel were performed, including FESEM, TEM, and XRD. The effects of various conditions on the adsorption process were investigated, such as hydrogel weight, Fe (II) ion concentration, equilibrium time, and adsorption isotherms. Iron ion adsorption increased from ۷۷.۲۵% to ۹۷.۹۱% as the weight of the hydrogel increased from ۰.۰۱ to ۰.۱ g/۵۰ mL. However, the adsorption capacity decreased from ۲۹.۱۴ to ۲۳۳.۳۳ mg/g at a fixed Fe (II) ion concentration of ۳۰ mg/L, an equilibrium time of ۱ hour, the temperature of ۲۵ °C, and a stirring speed of ۱۵۰ rpm. As the equilibrium time increased, both the adsorption efficiency and removal percentage rose. In addition, increasing the weight of the poly (AAC-co-AM) hydrogel led to an increase in the removal percentage. The results revealed that the adsorption efficiency of poly (AAC-co-AM) hydrogel was ۵۵.۶۲ mg/g with a removal percentage of ۹۲.۷۸% at pH ۷, a dose of ۰.۱ g/۵۰ mL, an equilibrium time of ۱ hour, an Fe (II) ion concentration of ۳۰ mg/L, and the temperature of ۲۵ °C. Beyond this, the adsorption efficiency began to decrease. Finally, the adsorption equilibrium was studied using the Langmuir and Freundlich isotherms. The data were best described by the Freundlich model.

کلیدواژه ها:

Hydrogel ، heavy metals ، Polymer ، Adsorption ، Removal ، Isotherm