Magnetophoresis of Superparamagnetic Nanoparticles Applied to the Extraction of Lanthanide Ions in the Presence of Magnetic Field

Abstract

Magnetic migration (magnetophoresis) and extraction of Dy 3+ ions by magnetite (Fe 3 O 4 ) nanoparticles functionalized with diethylenetriaminepentaacetic acid (MagNP@DTPA) were probed , using an analytical balance and an external weighing device comprising a miniature neodymium (Nd 2 Fe 14 B) magnet and a Lego ® system. Contrary to our expectation, when the paramagnetic Dy 3+ ions were captured by the superparamagnetic nanoparticles, the overall magnetization decreased, due to the anti-ferromagnetic dipolar interactions between the lanthanide ion and the superparamagnetic core. This finding allowed to monitor, in real time, the lanthanide extraction process (nanohydrometallurgy) and the nanoparticles migration in the magnetic field.

Superparamagnetic Maghemite-Based CdTe Quantum Dots as Efficient Hybrid Nanoprobes for Water-Bath Magnetic Particle Inspection

“…During the hybrid nanoprobe formation, just to guarantee that there is no free CTAB, it was centrifuged per 5 min in 10 000 rpm. At the end of this process, we used a magnetic gradient to separate the unreacted iron oxide nanoparticles (bigger magnetic response) from the hybrid nanoprobe (lower magnetic response) using a magnetophoretic technique 30 In the first part of the Figure 9, the magnetic stripes in the original card, used as a proof body (A), is not visible under any light, but after applying a drop of the hybrid nanoprobe onto the magnetic stripe (B), the code bar patterns are clearly revealed, both using MghNPs@QDG, (C), and MghNPs@ QDR, (D). This test corroborates the potential use of the magneto-fluorescence nanoparticles in water-bath MPI tests, as well as for capturing magnetic information, processing magnetic codes and images for many industrial applications.…”

“…It should be noted that the most common magnetic materials are based on iron oxide nanoparticles constituted by magnetite (Fe 3 O 4 ) and maghemite (γ-Fe 2 O 3 ). They exhibit strong superparamagnetic behavior in the presence of a magnetic field and their colloidal suspensions (also referred as ferrofluids) play an important role in biotechnology, medicine − as well as in the recent advances in mineral processing based on magnetic nanohydrometallurgy. − Although maghemite has a slightly smaller (∼25%) magnetic moment as compared with magnetite, it is more stable in air and has the advantage of exhibiting a much lower optical absorption in the visible region. In fact, in magnetite there are O 2– → Fe­(III) charge-transfer and Fe­(II) → Fe­(III) intervalence transitions spanning all the visible region, imparting a typical black color.…”

Green Processing of Strategic Elements Based on Magnetic Nanohydrometallurgy

“…63 The subject is related to magnetophoresis, an emerging area of investigation, aiming the use of superparamagnetic nanoparticles in separation processes, by analogy to electrophoresis. However, magnetophoresis is not completely understood yet, and has been the subject of many recent studies, [64][65][66][67][68] particularly focusing on theoretical aspects.…”

“…We have already proposed a rather simple and didactic approach, based on external weighing in the presence of a magnetic field, using an analytical balance, 61,63 and a versatile LEGO  toy setup. The typical arrangement involved a non magnetic assembly positioned on the balance plate, using a diamagnetic cantilever (nuclear magnetic resonance, NMR, or electron paramagnetic resonance, EPR, tube) to support the sample tube, as shown in Figure 5.…”

Inversion Algorithm of Fiber Bragg Grating for Nanofluid Flooding Monitoring

“…Magnetophoretic mobility not only contains information about the susceptibility of individual particles, but also reflects the particle size and viscosity of the fluent medium. The generated magnetic force is a function of magnetization saturation, particle volumes, and magnetic induction, as per below [31]:…”