Production of Micrometer-Sized Composite Polymer-Magnetic Spheres Using as Precursor Metallurgical Wastes

Abstract

Micrometer-sized composite polymer-magnetic spheres consisting of a magnetic-spherical core with a polystyrene shell were produced. The magnetic-spherical core was produced by plasma thermal conversion of waste powders precursor (iron oxide) generated during the conventional process of steel production. Precursor powders were projected into an Ar-He plasma plume using industrial thermal-spray equipment. The results are a total conversion of the precursor powders into magnetic-spherical particles with diameters in the micrometer size range. The surfaces of the magnetic-spheres were functionalized by a chemistry hydrolysis method using 3-aminopropyltrimethoxysilane (APTMS) and creating superficial amine structures that improved the adherence of the final polystyrene shells that was polymerized by adapting the miniemulsion process. The products at the different synthesis steps were characterized by diverse techniques, such as: X-ray diffraction (XRD), scanning electron microscopy (SEM), field emission scanning electron microscopy (FE-SEM), X-ray energy dispersive spectroscopy (EDS), Fourier Transformed Infrared spectroscopy (FTIR) and the magnetic properties were investigated with a vibrating sample magnetometer.

Production and Incorporation of Calcium Hydrolyzed Nano-particles in Alkali-Activated Mine Tailings

“…The EDS semiquantitative chemical composition indicates the silicon (Si) as primary element of composition in this gold mine tailings, where aluminum (Al), and iron (Fe) are the majority secondary elements, and magnesium (Mg), calcium (Ca), potassium (K), and sodium (Na) are present in minor quantities. The quantitative X-ray diffraction data from this gold MTs was also reported in a previous research work [53], the results indicates that the main crystalline mineral phase is namely quartz (SiO2) - [51,54], following by muscovite (KAl2(FOH)2 or (KF)2(Al2O3)3(-SiO2)6) [51], magnetite (Fe3O4) [36,55], albite (Na(AlSi3O8)) [51,54,56], C-A-S-H (Ca3Al(Al3SiO10)(OH)2) [53], N-A-S-H (Na17.6(Al16Si56O144)(H2O)38.4) [53]. Additionally, a percentage of amorphous phase was also identified [53].…”

“…The primary crystalline phases are quartz (SiO2) [36,51,67], albite (Na(AlSi3O8)) [ 51,54,56], muscovite (KAl2(FOH)2 or (KF)2(Al2O3)3(-SiO2)6) [51]. However, some additional crystalline phases were detected in low quantities; these phases are magnetite (Fe3O4) [36,55], portlandite [Ca(OH)2] [36], [68][69][70][71], calcite (CaCO3) [68,69], zeolite [36,69,72,73], C-S-H [68,72,74], and C-A-S-H [70]. The quantification of amorphous phases in each AAMs specimen was also determined.…”

Effect of the Class C Fly Ash on Low-Reactive Gold Mine Tailing Geopolymers

“…Quartz is less reactive than the other aluminosilicate constituents during the alkali activation processes; however, it provides some chemical reactivity in an alkaline environment, and once finely ground, can provide nucleation sites for dispersed formation of hydration products [ 28 , 29 ]. In addition, other phases, such as muscovite [ 20 ], magnetite [ 27 , 30 , 31 ], and albite [ 27 , 29 ] were present in very low percentage. Sodium aluminum silicate hydrate (N-A-S-H) [ 28 ], and calcium aluminum silicate hydrate (C-A-S-H) [ 28 ] were also identified.…”

Spectrally encoded microspheres for immunofluorescence analysis

“…146 Sometimes, however, unusual precursors, such as metallurgical wastes are used to synthesize the magnetic-spherical core with a PS shell. 147 Particular interest today is directed to novel Janus particles combining fluorescent and magnetic properties 148 or composite colloids with anisotropic structures, e.g. Fe 3 O 4 − PS-SiO 2 .…”

“…Silicone magnetic spheres are also designed for replacing magnetic PS spheres in applications where either large magnetic forces or minimal autofluorescence is required 146 . Sometimes, however, unusual precursors, such as metallurgical wastes are used to synthesize the magnetic‐spherical core with a PS shell 147 …”