PURPOSE: To enable reaction and refinning of two liquids, by flowing two liquids to the specified electrolytic cell having the electrodes separated with the diaphragm.

CONSTITUTION: One liquid out of two liquids flows to the electrolytic cell E from the cell 21 with the pump P1, it is circulated from the outlet 12 to the cell 21, and another liquid flows in the disphragm 9 from the inlet 6' with the pump P2 from the cell 20 and it is circulated in the cell 20 via the outlet 5'. With this state, DC current flows to the electrodes 7, 8. Thus, ions produced in either one of two lquids migrate to another liquid through the diaphragm and become nex liquid of substance through electrochemical reaction and stored in the cell 20, for example. Further, either one of two liquids can be refined through the migration of ions and if two are of the same type, the concentration can be incrased.