A differential pressure type high pressure water electrolysis apparatus has a flow passage forming member for supplying water to an anode. In the flow passage forming member, there are formed a water receiving section for receiving water supplied from the exterior, a distributing path for distributing the water that has flowed into the water receiving section, a converging path into which a surplus supplied amount of water flows, and a water discharging section for receiving the water inside the converging path and discharging it to the exterior. The positions of the distributing path and the converging path are offset from an opposing position where a seal member faces toward a pressure resistant member that surrounds the seal member from the exterior.

A platform technology that uses a novel membrane electrode assembly, including a cathode layer, an anode layer, a membrane layer arranged between the cathode layer and the anode layer, the membrane conductively connecting the cathode layer and the anode layer, in a CO.sub.x reduction reactor has been developed. The reactor can be used to synthesize a broad range of carbon-based compounds from carbon dioxide and other gases containing carbon.

A membrane-electrode-gasket assembly for alkaline water electrolysis, the assembly including: a separating membrane having first and second membrane faces; a first electrode arranged in contact with the first membrane face; and an insulating gasket holding the membrane and the electrode as one body, the gasket including: first and second faces for contacting with anode- and cathode-side frames respectively; a slit part opening toward an inner side of the gasket and receiving the entire peripheries of the membrane and the electrode; first and second parts facing with each other across the slit part; and a continuous part arranged on an outer periphery side of the slit part, uniting the first and second parts into one body, and sealing an outer periphery end of the slit part, wherein the first and second parts sandwich therebetween to hold the entire peripheries of the membrane and the electrode received in the slit part into one body.

A method of removing carbon dioxide from an atmosphere and generating hydrogen includes capturing carbon dioxide from the atmosphere in an alkaline capture solution, sending the alkaline capture solution to a series of electrolyzers in a CO.sub.2-rich path, wherein each electrolyzer cell raises the acidity of the input CO.sub.2-rich solution to produce an acidified CO.sub.2-rich solution, removing carbon dioxide from the acidified CO.sub.2-rich solution at a carbon removal unit to produce a CO.sub.2-poor solution, sending the CO.sub.2-poor solution to the series of electrolyzers in a return path, wherein each electrolyzer raises the alkalinity of the return CO.sub.2-poor solution to produce a basified CO.sub.2-poor solution, wherein a difference in pH between the CO.sub.2-rich solution and the CO.sub.2-poor solution within each electrolyzer is less than 3, and returning the basified CO.sub.2-poor solution to the carbon dioxide capture unit operation.

An expanded ion-exchange membrane electrolysis cell comprises an anode plate, a cathode plate, at least one bipolar electrode plate, a first ion-exchange membrane plate, a second ion-exchange membrane plate, a plurality of hydrogen chambers and a plurality of oxygen chambers. Wherein, a hydrogen outlet channel, an oxygen outlet channel and a water inlet channel are formed in the expanded ion-exchange membrane electrolysis cell. The hydrogen outlet channel is coupled to each of the plurality of hydrogen chambers, and the oxygen outlet channel and the water inlet channel are coupled to each of the plurality of oxygen chambers to provide the expanded ion-exchange membrane electrolysis cell capable of diverting gas and liquid after electrolyzing water.

Disclosed herein are various layered, carbon-containing materials for use in reducing carbon dioxide. In certain embodiments, the materials comprise single wall carbon nanotubes (SWNTs).

A hydrogen supply system includes an electrochemical hydrogen pump which includes: an electrolyte membrane; an anode provided on a first surface of the electrolyte membrane; a cathode provided on a second surface of the electrolyte membrane opposite to the first surface; and a current adjuster adjusting a current amount flowing between the anode and the cathode, and which performs a hydrogen supply operation by allowing a current to flow between the anode and the cathode using the current adjuster so as to boost the pressure of hydrogen which is supplied to an anode side at a cathode side and to supply the pressure-boosted hydrogen to a hydrogen demander; and a dew point adjuster adjusting a dew point of a mixed gas in which a hydrogen-containing gas which is discharged from the anode side and a hydrogen-containing gas which is supplied from an outside are mixed together.

Various embodiments may include an electrolyzer for electrochemical utilization of carbon dioxide comprising: an electrolysis cell defining an anode space and a cathode space; an anode; a cathode; a first cation-permeable membrane disposed between the anode space and the cathode space; and a layer comprising an anion-selective polymer disposed between the first membrane and the cathode. The anode directly adjoins the first cation-permeable membrane and the layer covers at least part of the cathode but not all of the cathode.

A membrane electrode assembly for an electrochemical cell, in particular a co-electrolysis cell for CO.sub.2 reduction reaction, can overcome the problem of parasitic CO.sub.2 pumping from cathode to anode side and, at the same time, maintain good Faradaic efficiency towards CO.sub.2 reduction reaction in a co-electrolysis system where pure or diluted gaseous CO.sub.2 is used. The assembly includes an MEA, having an anode, a cathode, a polymer ion exchange membrane between cathode and anode, an additional ion exchange polymer film between the cathode and the polymer ion exchange membrane and a discontinuous interface formed between the additional polymer film located at the cathode side and the ion exchange membrane.

An electrolytic cell for generating hydrogen through the electrolysis of water, including an anodic compartment and a cathodic compartment separated by a solid polymeric electrolyte alkaline membrane. The anodic compartment includes a positive electrode or anode at least partially submerged in a layer of water, and the cathodic compartment includes a negative electrode or cathode. The cell is arranged between a first closing plate and a second closing plate. A tie-rod, provided in the central portion of the first closing plate, passes through the first closing plate, the cell and the second closing plate. A central collector for conveying the hydrogen generated in the cathodic compartment is arranged coaxially to the tie-rod and is in communication with the cathodic compartment through an opening formed in the tie-rod.