Acrylic acid-grafted polyaniline fibers for nickel ion removal from water: synthesis, characterization and adsorption kinetics

The ability of polyaniline-grafted acrylic acid (AA-g-PANI) to adsorb Ni was investigated in this study. AA-g-PANI as an efficient adsorbent in an aqueous solution to remove Ni ions was prepared using irradiation-induced grafting. The AA-g-PANI was characterized using Fourier transform infrared spectroscopy and field-emission scanning electron microscope to confirm the formation of new acrylic acid groups onto polyaniline. The efficiency of grafted sample on the adsorption of Ni ion was done using the batch method, whereas the metal ion content in the solution before and after adsorption was measured using atomic adsorption spectrometry. The adsorption and kinetics study of the process is analyzed using variables, such as the effects of the initial concentration of the metal ion, contact time, pH of solution, and adsorbent dosage. The kinetic data were well suited to the pseudo-second-order kinetic model, which resembled the AA-g-PANI chemical adsorption. The highest adsorption capacity for AA-g-PANI was 18.12 mg g−1 can be reached at equilibrium concentrations of 100 mg L−1 at room temperature. While the best adsorption capacity for effect of dosage is 12.92 mg g−1 and 15.53 mg g−1 for effect of pH.