Separation of Ni (II) Ions using Maghemite Nanoparticle Enriched with Pistachio Nut Shell Activated Carbon

In this research, the applicability of maghemite (?-Fe3O4) nanoparticle enriched with pistachio nut shell activated carbon (PCNS-AC) for the separation of Ni (II) ions from aqueous solution was investigated. The ?-Fe3O4 nanoparticles were synthesized using a sol-gel method. The ?-Fe3O4 nanoparticles of the adsorbent were characterized by surface area Brunauer, Emmett and Teller (BET), scanning electron microscopy (SEM), transmission electron microscopy (TEM), and Fourier transform infrared (FTIR) spectroscopy and the zero point charge (pHZPC). The adsorption isotherm data were analyzed using the Langmuir, Freundlich, Redlich-Peterson, and Koble-Corrigan models. The best fit for the equilibrium process was the Koble-Corrigan model. The kinetic studies indicate that the adsorption follows the pseudo-second-order kinetics. The rate of adsorption improves with increasing temperature, and the process is endothermic with ?H value of 196.87 kJ mol-1. The activation energy of the adsorbent was calculated to be 519.62 kJ mol-1. The results also reveal that ?-Fe3O4-PCNS-AC from agriculture biomass can be an attractive option for metal removal from industrial effluent.