[M-TT42] Frontiers in Geochemistry

[MTT42-08] On-site Magnetic Separation of Heterogeneous Geological Particles

*Chiaki Uyeda¹ (1.Institute of earth and Space Science Graduate School of Science Osaka University)

Keywords:magnetic separation, material analysis, on-site analysis

A principle to perform chemical analysis of a solid sample in a non-descrutive manner was proposed based on its translation caused by a magnetic force. The field was generated by a permenent magnetic circuit;note that most solids, whihc are diamagnetic or weakly paramagnetic materials, were not considered to cause dynamic motions at a low field intensity.Here the practicability of the aforementioned technique was examined on single mg-size particles with various diamagnetic susceptibility (χ_dia), whihc was reproduced from its velocity v , assuming a classical energy conservation law, and practicability of identifying its material was confirmed; identification is performed by collating the meausred χ_dia with a list of published values. Th origin of χ_dia of a material is mainly attributed to its configuration of electron orbitals; hence, by using these parameters, a reliable material identification is possible which derive from its intrinsic structure. The experimental v did not depennd on particle mass m ; unlike the conventional magnetization measurements, χ_dia was obtained without measuring m. Similar m-independent property, as seen in the translations, was previously observed in the period of magnetic oscillation of mg-size silica-chips, and was obtained without measuring m. The m-independent properties appeared in the two motions because they were driven by body forces which were proportional to m, and in principle, magnetization of a very small sample is detected even if m of particle is difficult to obtain. Reliability of chemical analysis based on field-induced motions increases by parallelly consulting χ_dia . By realizing the proposed measurements in nm-size particles, extent of structural reconstruction in the surface layers, which generally proceed with reduction of particle diameter, are estimated from the anomalies observed in χ_dia values.[1]Uyeda et al., (2010) J. Phys. Soc. Jpn. 79, 064709, [2] Hisayoshi, et al, (2016) Sci. Rep 6, 38431. [3]Uyeda et al, (2019) Sci. Rep 9, 3931.