Method for electrolyzing alkaline water

Abstract

Provided is an alkaline water electrolysis method capable of reducing or preventing degradation in cathode and anode performance even in an operation of repeated cycles of frequent starting and stopping, and/or even in an operation involving a significant output variation. The present invention provides an alkaline water electrolysis method including repeated cycles of intermittent operation, including an electrolysis step of performing alkaline water electrolysis including storing an electrolytic solution () in a circulation tank (), feeding the electrolytic solution () in the circulation tank () to an anode chamber () and to a cathode chamber (), returning an electrolytic solution generated in the cathode chamber () and an electrolytic solution generated in the anode chamber () to the circulation tank (), mixing together these electrolytic solutions in the circulation tank (), and recirculating the mixed electrolytic solution to the anode chamber () and to the cathode chamber (), and a step of adding a catalyst activation material formed of a metal salt soluble in the electrolytic solution () prior to starting of the electrolysis step; and in the electrolysis step, a metal component in the catalyst activation material is deposited on a surface of the cathode.