Magnetic Nanocomposite Hydrogel based on Arabic Gum for Remediation of Lead(II) from Contaminated Water

A new organic/inorganic biosorbent hydrogel consisting in Arabic gum (AG), Polyamidoxime(PAO) and CuFe۲O۴ was synthesized by grafting copolymerization method. The first step was the preparation of CuFe۲O۴ magnetic nanoparticles by the coprecipitation method. Next, using a crosslinker and a radical initiator, acrylonitrile was grafted onto Arabic gum (AG) in the existence of CuFe۲O۴ nanoparticles to produce Arabic gum-g-polyacrylonitrile/CuFe۲O۴ (AG-g-PAN/CuFe۲O۴ ) nanocomposite hydrogel. In the last step, the acrylonitrile groups in the nanocomposite hydrogel were modified using hydroxylamine hydrochloride to obtain Arabic gum-g- polyamidoxime/CuFe۲O۴ (AG-g-PAO/CuFe۲O۴) nanocomposite hydrogel. X-ray diffraction (XRD), scanning electron microscopy image (SEM), Fourier transformed infrared (FT-IR), energy-dispersive X-ray analysis (EDX), Caron-Hydrogen-Nitrogen (CHN) analysis, zeta potential, and Brunauer-Emmett-Teller (BET) analyses. vibrating sample magnetometer (VSM) and thermogravimetric analysis (TGA) were used to characterize the produced nanocomposite. The adsorption effectiveness of AG-g-PAO/CuFe۲O۴ for the removal of Pb(II) from aqueous solutions was investigated under various experimental settings, including starting Pb(II) concentration, contact time, adsorbent dose, and pH. The Langmuir isotherm model accurately categorised the experimental adsorption data, and the maximum adsorption capacity (Qmax) of the produced biosorbent for Pb(II) was determined to be ۱۹۲.۳۰ mg/g. The pseudo-second-order model suited the adsorption kinetic data well. Additionally, after three consecutive cycles, the AG-g-PAO/CuFe۲O۴ can be successfully reused without a significant loss in adsorption performance.