Asahi Kasei Kabushiki Kaisha

Yousuke Uchino

Yasuhide Noaki

Jun Ohno

Yusuke Suzuki

Shinji Hasegawa

Kenji Nakagawa

Norikazu Fujimoto

Keiji Miyoshi

Hisanao Aoki

An object of the present disclosure is to suppress mixing of gases generated during an operation when supply of electric power is stopped, to thereby shorten the time required for restarting after the electric power is stopped. An electrolysis system of the present disclosure includes an electrolyzer including an electrolytic cell in which an anode and a cathode are overlapped with each other having a diaphragm interposed therebetween, and a liquid surface level control unit which is operated when an electric conduction to the electrolyzer is stopped to adjust a liquid surface level of an electrolytic solution in the electrolytic cell.

Electrolysis system and method of use of the same

An alkaline water electrolyzer includes at least two outer frames, a gasket, and a diaphragm. The at least two outer frames are stacked so as to overlap at least in part in a circumferential direction. The gasket is sandwiched between the two outer frames. The gasket can be in contact with the outer frames over the entire circumferential direction. In an inner peripheral surface of the gasket, a slit is formed along the circumferential direction. The gasket has a first protrusion portion. The first protrusion portion protrudes over the entire circumferential direction at a position overlapping the slit when viewed from a thickness direction of the slit. A diaphragm is caught in the slit of the gasket. A volume ratio of volume of the first protrusion portion, to volume between a bottom of the slit and an end of the diaphragm, is between 0.5 and 100 inclusive.

Alkaline water electrolyzer

A method of producing hydrogen using a water electrolysis system comprising at least an electrolyzer and a purifier for removing oxygen in a hydrogen gas generated in the electrolyzer. The method includes controlling a concentration of oxygen in a hydrogen gas to be introduced to the purifier to be constantly less than 0.5 volume % when the electrolyzer is operated at least under a current density of 0.5 kA/mor greater; and further controlling Ob/Oa to be less than 10.0, where Oa represents the concentration of oxygen in the hydrogen gas to be introduced to the purifier when the electrolyzer is operated under a current density of 2.0 kA/m, and Ob represents the concentration of oxygen in the hydrogen gas to be introduced to the purifier when the electrolyzer is operated under a current density of 0.2 kA/m.

Method of producing hydrogen

Provided are a gasket and an electrolyzer capable of preventing an electrolyte or a gas from leaking from a diaphragm. An annular gasket includes first and second surfaces which respectively contact a frame near a positive electrode and a frame near a negative electrode and a slit portion which is opened inward and is provided in the entire periphery of the gasket so as to accommodate an edge of an ion-permeable diaphragm.

Gasket and electrolyser

A bipolar alkaline water electrolysis unit incorporated in an electrolytic cell for electrolyzing an electrolytic solution of alkaline water to obtain oxygen and hydrogen, the bipolar alkaline water electrolysis unit including an oxygen generating anode, a hydrogen generating cathode, a conductive partition wall that separates the anode and the cathode from each other, and an outer frame that surrounds the conductive partition wall, wherein a gas and electrolytic solution passage is provided at an upper portion of the conductive partition wall and/or the outer frame, and an electrolytic solution passage is provided at a lower part of the conductive partition wall and/or the outer frame.

Growing community of inventors

Tokyo, Japan

Yousuke Uchino