Sorption Studies of Chromate by Iron Oxide from Drinking Water

Chromium is well-thought-out heavy metal which is one of the enormously lethal due to its cancer-causing nature. In this study, iron oxide is used as adsorbent for chromate removal from aqueous solution as a function of pH, time, temperature, concentration of adsorbate and media dosage. The influence of pH on Cr (VI) sorption by iron oxide reveals that adsorption is significantly increased as pH is decreased from 8 to 2. The sorption rate is detected to be higher in the beginning and then it remains constant after 120 min of equilibrium time. The removal of Cr (VI) is found to be greater at higher temperature, which confirms the endothermic nature of Cr (VI) adsorption by iron oxide. Whereas, the kinetic investigations confirm that the chromate adsorption follows the pseudo second order with kinetic energy in the range of 8.4–83.7 kJ mol−1.

Photocatalytic Iron Oxide Micro-Swimmers for Environmental Remediation

Harvesting energy from photochemical reactions has long been studied as an efficient means of renewable energy, a topic that is increasingly gaining importance also for motion at the microscale. Iron oxide has been a material of interest in recent studies. Thus, in this work different synthesis methods and encapsulation techniques were used to try and optimize the photo-catalytic properties of iron oxide colloids. Photodegradation experiments were carried out following the encapsulation of the nanoparticles and the Fenton effect was also verified. The end goal would be to use the photochemical degradation of peroxide to propel an array of swimmers in a controlled manner while utilizing the Fenton effect for the degradation of dyes or waste in wastewater remediation.

Quantum Mechanical Study of γ-Fe2O3 Nanoparticle as a Nanocarrier for Anticancer Drug Delivery

Using density functional theory (DFT), noncovalent interactions and four mechanisms of covalent functionalization of melphalan anticancer drug onto γ-Fe2O3 nanoparticles have been studied. Quantum molecular descriptors of noncovalent configurations were investigated. It was specified that binding of melphalan onto γ-Fe2O3 nanoparticles is thermodynamically suitable. Hardness and the gap of energy between LUMO and HOMO of melphalan are higher than the noncovalent configurations, showing the reactivity of drug increases in the presence of γ-Fe2O3 nanoparticles. Melphalan can bond to γ-Fe2O3 nanoparticles through NH2 (k 1 mechanism), OH (k 2 mechanism), C=O (k 3 mechanism) and Cl (k 4 mechanism) groups. The activation energies, the activation enthalpies and the activation Gibbs free energies of these reactions were calculated. Thermodynamic data indicate that k 3 mechanism is exothermic and spontaneous and can take place at room temperature. These results could be generalized to other similar drugs.