Selective transfer of cations between two electrolytes using the intercalation properties of Chevrel phases

A device based on an electrochemical transfer junction (constituted by MxMo6S8 or MxMo6Se8) placed between two tanks allows the transfer of cations by application of current density controlled between electrodes placed in tanks. The transfer protocol was tested on different mixed electrolytes containing cations directly engaged in the batteries industry (M2+ = Co2+, Ni2+, Cd2+, Zn2+, Mn2+, Cu2+). Good performances of the process are provided until 1.6 mA cm−2. The electrolysis through an electrochemical transfer junction made of Chevrel phases represents a suitable method for the selective extraction of cations with appreciable selectivity rates with an appropriate choice of the host lattice (sulfide or selenide). Remarkable separations between Co/Ni, Zn/Mn with Mo6S8 and Cd/Zn, Cd/Ni, Cd/Co and Zn/Ni, with Mo6Se8 were observed.