There is disclosed an electrolyser (10, 20, 50) for operation at supercritical conditions, in which chambers (200, 210, 520) for retaining respective fluid reaction products are separated by a porous wall which permits a flow of electrolyte fluid therethrough and which inhibits a reverse flow of the respective reaction product. A controller is to control flow control equipment to maintain supercritical conditions for the electrolyte fluid. There is also disclosed a method of operating an electrolyser, and methods of manufacturing compound porous electrodes for such electrolysers.

There is disclosed an electrolyser (10, 20, 50) for operation at supercritical conditions, in which chambers (200, 210, 520) for retaining respective fluid reaction products are separated by a porous wall which permits a flow of electrolyte fluid therethrough and which inhibits a reverse flow of the respective reaction product. A controller is to control flow control equipment to maintain supercritical conditions for the electrolyte fluid. There is also disclosed a method of operating an electrolyser, and methods of manufacturing compound porous electrodes for such electrolysers.

An electrolyser (100) for continuous electrolysis of gaseous carbon dioxide, CO.sub.2, includes an anode with an anode catalyst layer, a cathode with a cathode catalyst layer formed as a gas-diffusion electrode, GDE, an ion-conducting separator layer arranged between the anode and the cathode, an anode compartment formed in contact with the anode, and a cathode compartment formed in contact with the cathode. A flow of gaseous CO.sub.2 is directed through the cathode compartment and a flow of anolyte is directed through the anode compartment to perform electrolysis of said CO.sub.2. From time to time, one of (i) a liquid flow containing alkali or alkali-earth metal cations, or (ii) a gaseous flow comprising at least one of isopropanol vapor, ethanol vapor, gaseous ammonia, N.sub.2H.sub.4, HCl, sulfur dioxide and nitrous oxide is directed through the cathode compartment, thereby activating the GDE.

An electrolyser (100) for continuous electrolysis of gaseous carbon dioxide, CO.sub.2, includes an anode with an anode catalyst layer, a cathode with a cathode catalyst layer formed as a gas-diffusion electrode, GDE, an ion-conducting separator layer arranged between the anode and the cathode, an anode compartment formed in contact with the anode, and a cathode compartment formed in contact with the cathode. A flow of gaseous CO.sub.2 is directed through the cathode compartment and a flow of anolyte is directed through the anode compartment to perform electrolysis of said CO.sub.2. From time to time, one of (i) a liquid flow containing alkali or alkali-earth metal cations, or (ii) a gaseous flow comprising at least one of isopropanol vapor, ethanol vapor, gaseous ammonia, N.sub.2H.sub.4, HCl, sulfur dioxide and nitrous oxide is directed through the cathode compartment, thereby activating the GDE.

An electrochemical system includes a first stack, a first tank for storing high-pressure gas output from the first stack, a check valve disposed in a flow path connecting the first stack and the first tank, a first pressure sensor and a second pressure sensor connected respectively to the upstream and the downstream of the check valve, and a control unit. The control unit determines that an electrolyte membrane has been damaged when the pressure difference between the upstream and the downstream of the check valve exceeds a predetermined pressure.

An electrochemical system includes a first stack, a first tank for storing high-pressure gas output from the first stack, a check valve disposed in a flow path connecting the first stack and the first tank, a first pressure sensor and a second pressure sensor connected respectively to the upstream and the downstream of the check valve, and a control unit. The control unit determines that an electrolyte membrane has been damaged when the pressure difference between the upstream and the downstream of the check valve exceeds a predetermined pressure.

A system and methods for electrolysis of saline solutions are provided. An exemplary system provides a tandem electrolysis cell. The tandem electrolysis cell includes a common enclosure that has two chambers. A first chamber is separated from a second chamber by a cation selective membrane. A common anode and a first cathode (cathode A) are disposed in the first chamber. The first cathode and the common anode are configured to electrolyze a saline solution to hydrogen and oxygen. A second cathode (cathode B) is disposed in the second chamber. The second cathode and the common anode are configured to electrolyze a brine solution in the first chamber to form chlorine and water in the second chamber to form hydrogen and hydroxide ions.

A modular electrolyzer system including a power module and a generator module wherein the power module and the generator module are integrated with a hydrogen collection component and a steam delivery component, the hydrogen collection component and the steam delivery component being disposed on a structural base.

An electrochemical cell has a first reaction chamber having a first electrode, a second reaction chamber having a second electrode, a membrane-electrode assembly having an ion-exchange membrane, and a photovoltaic system for absorbing solar energy and producing an output voltage between a first output terminal selectively couplable to the first electrode and a second output terminal selectively couplable to the second electrode. The ratio between a photosensitive area of the photovoltaic system and an active area of the first and second electrodes is less than or equal to fifty. A plurality of photovoltaic cells is selectively couplable between the first and second output terminals. An electronic control unit couples the photovoltaic cells as a function of at least one among one or more user-settable parameters, one or more signals received from an external control unit, one or more signals received from one or more sensors included in the electrochemical cell.

An electrochemical cell has a first reaction chamber having a first electrode, a second reaction chamber having a second electrode, a membrane-electrode assembly having an ion-exchange membrane, and a photovoltaic system for absorbing solar energy and producing an output voltage between a first output terminal selectively couplable to the first electrode and a second output terminal selectively couplable to the second electrode. The ratio between a photosensitive area of the photovoltaic system and an active area of the first and second electrodes is less than or equal to fifty. A plurality of photovoltaic cells is selectively couplable between the first and second output terminals. An electronic control unit couples the photovoltaic cells as a function of at least one among one or more user-settable parameters, one or more signals received from an external control unit, one or more signals received from one or more sensors included in the electrochemical cell.