METHOD FOR PROCESSING IRON GROUP METAL ION-CONTAINING LIQUID, AND PROCESSING UNIT

摘要

PROBLEM TO BE SOLVED: To improve the permeability rate of a cation exchange membrane for an iron group metal ion to increase treatment efficiency when an iron group metal ion in an iron group metal ion-containing liquid is removed by making the iron group metal ion in the iron group metal ion-containing liquid permeate a cation exchange film to move to an electrodeposition solution and removing an iron group metal in the electrodeposition solution onto a cathode through electrodeposition.SOLUTION: A liquid containing an iron group metal ion and an electrodeposition solution containing a ligand that forms a complex with the iron group metal ion are introduced into an electrodialysis tank having a plurality of cation exchange membranes provided therein, and the iron group metal ion in the iron group metal ion-containing liquid is made to permeate the cation exchange films to move to the electrodeposition solution, thereby removing the iron group metal ion. The electrodeposition solution containing the iron group metal ion is introduced from the electrodialysis tank to an electrodeposition tank having an anode and cathode provided therein to electrodeposit an iron group metal onto the cathode, thereby removing the iron group metal ion from the electrodeposition solution. The electrodeposition solution having the iron group metal ion removed therefrom is made to circulate in the electrodialysis tank.SELECTED DRAWING: Figure 1