Decontamination of arsenic(V)-contained liquid phase utilizing Fe₃O₄/bone char nanocomposite encapsulated in chitosan biopolymer

The application of a novel nanocomposite synthesized through the combination of Fe₃O₄ nanoparticles and bone char particles for the adsorption of As(V) ions in the aquatic medium was investigated. As-prepared nanocomposite was immobilized by using chitosan biopolymer. The characterization of the nanocomposite was performed via SEM, XRD, FT-IR, and BET together with the determination of zero-point charge of the adsorbent surface. As results, the obtained experimental data were fitted well with pseudo-first-order kinetic model (R² = 0.997) and Langmuir isotherm model (R² = 0.990) with the maximum adsorption capacity of about 112 μg/g. Increasing the dosage of nanocomposite and initial solute concentration led to increasing the adsorption capacity of As(V) ions, while decreasing the solution temperature resulted in the enhanced adsorption process. According to the results of thermodynamic study, the adsorption of As(V) ions onto the nanocomposite was spontaneous and exothermic in nature.