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arXiv · 2107.02770

Neutron Imaging of Paramagnetic Ions: Electrosorption by Carbon Aerogels and Macroscopic Magnetic Forces

T. A. Butcher·L. Prendeville·A. Rafferty·P. Trtik·P. Boillat·J. M. D. Coey
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Abstract

The electrosorption of Gd$^{3+}$ ions from aqueous 70 mM Gd(NO$_3$)$_3$ solution in monolithic carbon aerogel electrodes was recorded by dynamic neutron imaging. The aerogels have a bimodal pore size distribution consisting of macropores and mesopores centered at 115 nm and 15 nm, respectively. After the uptake of Gd$^{3+}$ ions by the negatively charged surface of the porous structure, an inhomogeneous magnetic field was applied to the system of discharging electrodes. This led to a convective flow and confinement of Gd(NO$_3$)$_3$ solution in the magnetic field gradient. Thus, a way to desalt and capture paramagnetic ions from an initially homogeneous solution is established.

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T. A. Butcher, L. Prendeville, A. Rafferty, P. Trtik, P. Boillat, J. M. D. Coey. 2021-07-06. Neutron Imaging of Paramagnetic Ions: Electrosorption by Carbon Aerogels and Macroscopic Magnetic Forces. https://doi.org/10.1021/acs.jpcc.1c06031

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