۲-Acrylamide-۲-Methylpropane Sulfonic Acid Hydrogels; Preparation, Characterization, and Removal of Heavy Metals Pb۲+ and Cu۲+ from Wastewater

The aim of the study was the preparation and characterization of ۲-Acrylamide-۲-methylpropane sulfonic acid (AMPS) hydrogel with the intent to remove Lead (Pb۲+) and Copper (Cu۲+) heavy metals from wastewater. AMPS hydrogels were prepared by the free radical polymerization method at ۷۰℃ for six hours. Potassium persulfate (KPS) was used as an initiator, and N,N'-Methylene-bis-acrylamide as a crosslinking agent. The swelling properties of hydrogels were studied in diverse conditions, such as temperature, ion strength, and pH. NaOH neutralized AMPS in ۵۰%, ۶۵%, and ۷۵% w/w. AMPS monomer showed absorption by UV spectrophotometer at ۲۲۹ nm. After neutralization, absorption was established at ۲۰۳, ۲۱۳, and ۲۰۰ nm for ۵۰%, ۶۵%, and ۷۵% w/w solution, respectively. This study showed a robust, complex formation between SO۳- and Na+. The maximum swelling of AMPS hydrogels was determined as ۱۶۰۰۰% in ۶۵% w/w NaOH and pH=۷. The swelling behavior of hydrogels was studied at ۲۵°C, ۵۰°C, and ۷۵°C. The maximum swelling was ۲۲۰%, which was seen at ۷۵°C. To evaluate the effect of ionic strength on hydrogel swelling, NaCl and KCl were used in different mol concentrations. In this research, the swelling properties in ۰.۰۰۰۰۱M were more than ۰.۰۰۱M. FT-IR and TGA were used to characterize the structural and thermal properties. Atomic Absorption spectroscopy was performed to evaluate the removal of the heavy metals (Cu۲+ and Pb۲+) in wastewater. Morphologic investigation was studied by the Scanning electron microscopy (SEM) micrographs.

کلیدواژه ها:

Bifunctional Hydrogel ، Swelling properties ، Atomic absorption ، Water Remediation ، neutralization ، Scanning Electron Microscopy (SEM)