Retention potential of contaminants by (nano)magnetite in batch and microfluidic systems

(Nano)magnetite (Fe3O4) has been suggested to be a significant reductant for contaminants due to its great adsorption capacity and ability to retain metals on its high specific surface. Its use has become an emerging technology for the treatment of contaminated land and water with a great potential to become an effective and low-cost alternative to conventional remediation techniques. We have taken advantage of a concept of the circular economy, exploiting an existing waste from the steel industry that HYMAG’IN company has transformed into magnetite, to study the immobilisation of As, Sb, and U in batch sorption systems and provide new insights into a new ‘green’ route for the decontamination of water. Moreover, given that polymeric coatings can maximize the adsorption capacity, we additionally, mimic those systems in a micro-scale format via the use of bionanocomposite and microfluidics to study time-dependent Sb reduction by nanomagnetite aggregates. Synchrotron X-ray Absorption Spectroscopy (XAS) is applied for the first time to such experimental systems to shed light into the role of nanomagnetite aggregates into the immobilization of Sb, as a novel remediation strategy.