Unlocking the magnetic potential of Fe2O3 nanoparticles by single-step synthesis of cobalt-infused nanomaterials for chromium removal
Bachir Yaou Balarabe, Primerose Bomokayi, Irédon Adjama, Abdoulkadri Ayouba Mahamane, Michael O. Daramola, Samuel A. Iwarere
Abstract
Abstract The study optimized the chromium removal capacity of Fe 2 O 3 nanoparticles through the infusion of cobalt using a single-step synthesis method. This approach not only enhanced their magnetic properties but also employs less-chemical synthesis techniques, ultimately yielding highly magnetic CoFe 2 O 4 nanoparticles and less impurities. The prepared materials underwent comprehensive testing, encompassing examinations of their optical properties, structure, chemical composition, and surface characteristics using various analyticals methods. In a span of 90 min under visible light exposure, CoFe 2 O 4 nanoparticles exhibit the ability to remove more that 90% of chromium. This was corroborated through analysis using Inductively Coupled Plasma-Optical Emission Spectroscopy (ICP-OES). Moreover, the study illustrates that increased temperatures amplify the endothermic process of chromium adsorption. Positive ΔH°, negative ΔS°, and heightened Cr(IV) adsorption are linked to the temperature effects on solubility, mobility, and dissolved oxygen. Both Langmuir (R 2 = 0.95, R L = 0.055) and Freundlich models (R 2 = 0.98, n = 0.69) suggest favorable adsorption. The efficient Cr(IV) adsorption by CoFe 2 O 4 nanocomposite is attributed to a rapid reaction rate and substantial capacity, following pseudo-second order kinetics (rate constant 0.01 g mg −1 min −1 , R 2 = 0.99). Graphical abstract