Abstract: Provided is an alkaline water electrolyzer in which leakage of aqueous alkali solutions is prevented. The alkaline water electrolyzer 10 includes an anode chamber frame 11 defining an anode chamber 12; a cathode chamber frame 17 defining a cathode chamber 18; a porous diaphragm 16 disposed between the anode and cathode chamber frames 11 and 17 and partitioning the anode and cathode chambers 12 and 18; an anode gasket 15 disposed on the anode chamber frame 11; and a cathode gasket 21 disposed on the cathode chamber frame 17, wherein when the anode and cathode chamber frames 11 and 17 are fastened, the porous diaphragm 16 is held between the anode and cathode chamber frames 11 and 17 via the anode and cathode gaskets 15 and 21 and the anode and cathode gaskets 15 and 21 are in contact with each other around the peripheral edge of the porous diaphragm 16 by compressing the anode and cathode gaskets 15 and 21.

Abstract: Provided is an alkaline water electrolyzer in which leakage of aqueous alkali solutions is prevented. The alkaline water electrolyzer 10 includes an anode chamber frame 11 defining an anode chamber 12; a cathode chamber frame 17 defining a cathode chamber 18; a porous diaphragm 16 disposed between the anode and cathode chamber frames 11 and 17 and partitioning the anode and cathode chambers 12 and 18; an anode gasket 15 disposed on the anode chamber frame 11; and a cathode gasket 21 disposed on the cathode chamber frame 17, wherein when the anode and cathode chamber frames 11 and 17 are fastened, the porous diaphragm 16 is held between the anode and cathode chamber frames 11 and 17 via the anode and cathode gaskets 15 and 21 and the anode and cathode gaskets 15 and 21 are in contact with each other around the peripheral edge of the porous diaphragm 16 by compressing the anode and cathode gaskets 15 and 21.

Abstract: Provided is a method of preventing reverse current flow through an ion exchange membrane electrolyzer, which method is capable of preventing a reverse current from being generated after stopping operation of the ion exchange membrane electrolyzer. A method of preventing reverse current flow through an ion exchange membrane electrolyzer 100, the ion exchange membrane electrolyzer 100 having an anode chamber 107 housing an anode, a cathode chamber 110 housing a cathode, an anode solution-supplying manifold 121 to feed anode solution to the anode chamber 107, and a cathode solution-supplying manifold 124 to feed cathode solution to the cathode chamber 110.

Abstract: Provided are an elastic cushion member and an ion exchange membrane electrolyzer using the same, which elastic cushion member can be installed even in an ion exchange membrane electrolyzer having such a small gap between an electrode and an electrode current collecting plate that a conventional elastic cushion member cannot be arranged therein. An elastic cushion member (10) has a pair of corrosion-resistant metal thin plates (11) arranged at a distance in parallel fashion and a fixing member (12) which fixes the pair of corrosion-resistant metal thin plates (11) and comprises a metal elastic body (13) wound between the pair of corrosion-resistant metal thin plates (11). The fixing member (12) is attached to the pair of corrosion-resistant metal thin plates (11) in a manner that enables detachment of the fixing member therefrom. The metal elastic body (13) is preferred to be a metal coil body.

Abstract: A diaphragm includes a porous supporting body and a polymer porous membrane. When one of surfaces of the porous membrane is defined as a surface A, the other surface opposite to the surface A is defined as a surface B, a section of the porous membrane parallel to the surfaces A and B is defined as a section C, an average pore diameter on the surface A is defined as an average pore diameter DA, an average pore diameter on the surface B is defined as an average pore diameter DB, and an average pore diameter on the section C is defined as an average pore diameter DC, the average pore diameters DA and DB are substantially equal to each other, and the average pore diameter DC is larger than each of the average pore diameters DA and DB.

Abstract: Provided is a cell for ion exchange membrane electrolysis obtained by improving the performance in electrolysis of an existing bipolar cell for ion exchange membrane electrolysis, in which a cathode partition wall and a rigid cathode being connected together by a plurality of intermediating V-shaped springs, by a simple method. It is a cell for ion exchange membrane electrolysis which is separated by an ion exchange membrane (7) into an anode chamber (1) having a rigid anode (1a) and an anode partition wall (1b) and a cathode chamber (2) having a rigid cathode (2a) and a cathode partition wall (2b), the rigid cathode (2a) and the cathode partition wall (2b) being connected together by a plurality of intermediating V-shaped springs (3).

Abstract: Provided are an anode for an ion exchange membrane electrolyzer which enables an aqueous solution of an alkali metal chloride to be electrolyzed at a lower voltage than a conventional anode and allows the concentration of an impurity gas included in an anode gas to be reduced and an ion exchange membrane electrolyzer using the same. The anode is an anode for an ion exchange membrane electrolyzer to be used in an ion exchange membrane electrolyzer that is separated by an ion exchange membrane into an anode chamber and a cathode chamber. The anode for an ion exchange membrane electrolyzer comprises at least one perforated flat metal plate 1 (expanded metal 1) and the thickness of the perforated flat metal plate 1 (expanded metal 1) ranges from 0.1 to 0.5 mm and the ratio of the short way SW to the long way LW (SW/LW) ranges from 0.45 to 0.55. The short way SW is preferably not more than 3.0 mm.

Abstract: An alkaline water electrolysis diaphragm includes: a polymer porous layer containing at least one polymer compound selected from polyether sulfone having a contact angle of 20 to 90° and polysulfone having the contact angle of 20 to 90°; and an organic fiber fabric layer coupled to the polymer porous layer. The polyether sulfone having the contact angle of 20 to 90° is at least one polymer compound selected from the group made of polyether sulfone, hydrophilic polyether sulfone, cationic polyether sulfone, and cationic hydrophilic polyether sulfone. The polysulfone having the contact angle of 20 to 90° is at least one polymer compound selected from the group made of polysulfone, hydrophilic polysulfone, cationic polysulfone, and cationic hydrophilic polysulfone.