Optimisation of the Flame Spheroidisation Process for the Rapid Manufacture of Fe3O4-Based Porous and Dense Microspheres

Jesús Molinar-Díaz; John Luke Woodliffe; Elisabeth Steer; Nicola A Morley; Paul D Brown; Ifty Ahmed

doi:10.3390/molecules28062523

Optimisation of the Flame Spheroidisation Process for the Rapid Manufacture of Fe₃O₄-Based Porous and Dense Microspheres

Molecules. 2023 Mar 9;28(6):2523. doi: 10.3390/molecules28062523.

Authors

Jesús Molinar-Díaz¹, John Luke Woodliffe¹, Elisabeth Steer², Nicola A Morley³, Paul D Brown^{1

2}, Ifty Ahmed¹

Affiliations

¹ Advanced Materials Research Group, Faculty of Engineering, University of Nottingham, University Park, Nottingham NG7 2RD, UK.
² Nanoscale and Microscale Research Centre, University of Nottingham, University Park, Nottingham NG7 2RD, UK.
³ Department of Materials Science and Engineering, University of Sheffield, Sheffield S1 3JD, UK.

Abstract

The rapid, single-stage, flame-spheroidisation process, as applied to varying Fe₃O₄:CaCO₃ powder combinations, provides for the rapid production of a mixture of dense and porous ferromagnetic microspheres with homogeneous composition, high levels of interconnected porosity and microsphere size control. This study describes the production of dense (35-80 µm) and highly porous (125-180 µm) Ca₂Fe₂O₅ ferromagnetic microspheres. Correlated backscattered electron imaging and mineral liberation analysis investigations provide insight into the microsphere formation mechanisms, as a function of Fe₃O₄/porogen mass ratios and gas flow settings. Optimised conditions for the processing of highly homogeneous Ca₂Fe₂O₅ porous and dense microspheres are identified. Induction heating studies of the materials produced delivered a controlled temperature increase to 43.7 °C, indicating that these flame-spheroidised Ca₂Fe₂O₅ ferromagnetic microspheres could be highly promising candidates for magnetic induced hyperthermia and other biomedical applications.

Keywords: calcium ferrites; ceramics; flame spheroidisation; magnetic hyperthermia; magnetic particles; magnetite; porous microspheres.

Abstract

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