TY - JOUR
T1 - Electrochemical measurement of solubility product of metal oxides in liquid metals by coulometric titration of oxygen
AU - Gregori, Giacomo
AU - Aerts, Alexander
AU - Gladinez, Kristof
AU - Rosseel, Kris
AU - Doneux, Thomas
AU - Lim, Jun
N1 - Score=10
PY - 2022/11/10
Y1 - 2022/11/10
N2 - We propose a new electrochemical method for the measurement of the solubility product of the oxide of a metal impurity, in a liquid metal solvent that is less easily oxidized than the metal impurity. When a known amount of oxygen is continuously added into the liquid metal by coulometric titration, the dissolved metal impurity reacts with the added dissolved oxygen, forming a metal oxide. By measuring the concentration of dissolved oxygen in the liquid metal solvent during the titration, the solubility product of the impurity metal oxide in the liquid metal solvent can be derived. From this solubility product, using thermochemical data of the known chemical species involved in the oxidation reaction, i.e. Sieverts’ constant of dissolved oxygen in the liquid metal solvent and the Gibbs free energy of formation of the impurity metal oxide, the elemental solubility of the metallic impurity element in the liquid metal solvent can be derived as well. In this work, we validate the method by measuring the solubility product of magnetite (Fe3O4) in molten lead-bismuth eutectic alloy (LBE), in the temperature range of 723–826 K.
AB - We propose a new electrochemical method for the measurement of the solubility product of the oxide of a metal impurity, in a liquid metal solvent that is less easily oxidized than the metal impurity. When a known amount of oxygen is continuously added into the liquid metal by coulometric titration, the dissolved metal impurity reacts with the added dissolved oxygen, forming a metal oxide. By measuring the concentration of dissolved oxygen in the liquid metal solvent during the titration, the solubility product of the impurity metal oxide in the liquid metal solvent can be derived. From this solubility product, using thermochemical data of the known chemical species involved in the oxidation reaction, i.e. Sieverts’ constant of dissolved oxygen in the liquid metal solvent and the Gibbs free energy of formation of the impurity metal oxide, the elemental solubility of the metallic impurity element in the liquid metal solvent can be derived as well. In this work, we validate the method by measuring the solubility product of magnetite (Fe3O4) in molten lead-bismuth eutectic alloy (LBE), in the temperature range of 723–826 K.
KW - Liquid metals
KW - Lead-bismuth eutectic
KW - Coulometric titration
KW - Solubility product
KW - Solubility
UR - https://ecm.sckcen.be/OTCS/llisapi.dll/overview/52004983
U2 - 10.1016/j.electacta.2022.141202
DO - 10.1016/j.electacta.2022.141202
M3 - Article
SN - 0013-4686
VL - 432
JO - Electrochimica Acta
JF - Electrochimica Acta
M1 - 141202
ER -