Ricerc@Sapienza

This study deals with the simulation of two alternative processes for the coupled production of metallic iron nanoparticles and the necessary reducing agent: hydrated hydrazine and sodium borohydride. After carrying out a sensitivity analysis to identify the optimal operating conditions for each process, the results have been interpreted in the light of energy and exergy analysis.

The effect of soil composition on the reduction of hexavalent chromium (Cr(VI)) by zero valent iron nanoparticles was studied. A model was proposed, to investigate both the effect of manganese oxide and the simultaneous effect of manganese dioxide and soil organic matter on the kinetic of Cr(VI) reduction. Fe(0) nanoparticles consumption by the reaction with dissolved oxygen, water and soluble Cr(VI) was taken into account.

This work deals with the treatment of a tannery wastewater by a mixed-iron coated olive stone bio-sorbent particles. Olive stones were used as the support to zero-valent iron and magnetite nanoparticles to develop a new material for the removal of chromium, organic matter and total phenols from the wastewater. The optimal operating conditions were determined in batch reactors, after which the process was scaled-up using fixed-bed columns in series.

The aim of this work was to investigate the optimization of iron nanoparticles production by spinning disk reactor. The influence of the two main operating parameters, i.e. rotational velocity and feed injection point position was investigated through evaluating the particle size distribution, the X-Ray powder diffraction spectra and metallic iron percentage production. Results showed that increasing both rotational velocity and the distance of reagents injection feed points from the disk centre led, to the production of metallic iron nanoparticles characterized by lower mean size.

The aim of this work was to investigate the aggregation of metallic iron nanoparticles in a Rushton equipped agitated vessel open at the atmosphere. The particles were synthetized using oxygen-free reagent solutions and subsequently were suspended in water in an open lab-scale agitated vessel. The particle size distribution, zeta-potential, pH and Fe(0) content were monitored over the time, up to the complete oxidation of the particles.

The aim of this work was to investigate the performances of a spinning disk reactor for the removal of nitrate from aqueous solutions, by using iron nanoparticles as reducing agent. The influence of three operating parameters, i.e. rotational velocity, feed injection point position and recirculation flow-rate was investigated through evaluating the nitrate reduction efficiency and kinetics. Increasing the rotational velocity led to a better nitrate reduction efficiency and faster kinetics.

This article proposes the aqueous system Cu-Fe(0)/NO3 ? mathematical modelling through a classical shrinking core model, taking into account the presence of dissolved oxygen in the reaction medium and considering it in the model equation. In this work the nitrate reduction to ammonia was assumed to occur onto the lab-made bimetallic nano zero-valent iron (nZVI) surface, simultaneously with the nZVI consumption due to the oxidation carried out by dissolved oxygen.