Tandem electrolysis cell

A system for electrolyzing seawater, comprising:

• a tandem electrolysis cell, comprising:
• a common enclosure comprising two chambers, wherein a first chamber is separated from a second chamber by a cation selective membrane;
• a common anode disposed in the first chamber, wherein the common anode is operated continuously;
• a first cathode (cathode A) disposed in the first chamber, wherein the first cathode and the common anode are configured to electrolyze a saline solution to hydrogen and oxygen in a first electrolysis reaction;
• a second cathode (cathode B) disposed in the second chamber, wherein 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 in a second electrolysis reaction, wherein the common anode is positioned between cathode A and cathode B;
• a controller to open valves, during the first electrolysis reaction, and close valves, during the second electrolysis on:
• a saline inlet port on the first chamber;
• an alkali inlet port on the first chamber;
• a first hydrogen outlet port proximate to cathode A on the first chamber;
• and
• an oxygen outlet port proximate to the common anode on the first chamber, the oxygen outlet port attached to in the first chamber;
• and
• the controller to open valves, during the second electrolysis reaction, and close valves, during the first electrolysis reaction on:
• a water inlet port on the second chamber;
• an alkali outlet port on the second chamber;
• a second hydrogen outlet port on the second chamber;
• and
• a chlorine outlet port proximate to the common anode on the first chamber, the chlorine outlet port attached to the first chamber,
• wherein the common anode is positioned between the oxygen outlet port and the chlorine outlet port;
• and
• an atmospheric water producer, wherein the atmospheric water producer comprises:
• a solar panel to generate electricity;
• a battery to store the electricity, wherein the battery powers the tandem electrolysis cell;
• a cooling system powered by the battery, wherein the cooling system harvests atmospheric moisture;
• and
• a water storage tank to collect the harvested atmospheric moisture, wherein the water storage tank provides the water to the second chamber.

A method for using a tandem electrolysis cell (TEC) to form hydrogen, oxygen, chlorine, and sodium hydroxide, comprising:

• determining if a sodium ion concentration in a first chamber of the TEC is below a threshold,
• and, if so, opening valves on:
• a saline inlet port on the first chamber;
• an alkali inlet port on the first chamber;
• a first hydrogen outlet port proximate to a first cathode (cathode A) on the first chamber;
• and
• an oxygen outlet port proximate to a common anode on the first chamber, the oxygen outlet port being attached to the first chamber;
• and
• closing valves on:
• a water inlet port on a second chamber;
• an alkali outlet port on the second chamber;
• a second hydrogen outlet port on the second chamber;
• and
• a chlorine outlet port proximate to the common anode on the first chamber, the chlorine outlet port being attached to the first chamber;
• and
• while the sodium ion concentration remains below the threshold, iterating:
• flowing saline water into a half-cell of the first chamber comprising cathode A;
• forming hydrogen at cathode A and oxygen at the common anode;
• and
• monitoring the sodium ion concentration in the first chamber;
• and
• determining if a pH in the second chamber of the TEC is below a threshold, and, if so,
• opening valves on:
• the water inlet port on the second chamber;
• the alkali outlet port on the second chamber;
• the second hydrogen outlet port on the second chamber;
• and
• the chlorine outlet port proximate to the common anode on the first chamber;
• and
• closing valves on:
• the saline inlet port on the first chamber;
• the alkali inlet port on the first chamber;
• the first hydrogen outlet port proximate to cathode A on the first chamber;
• and
• the oxygen outlet port proximate to the common anode on the first chamber;
• and
• while the pH remains below the threshold, iterating:
• flowing fresh water into a half-cell of a second chamber comprising a second cathode (cathode B);
• forming hydrogen and hydroxide ions at cathode B and oxygen at the common anode;
• and
• monitoring the pH in the first chamber,
• wherein the common anode is positioned between cathode A and cathode B, and between the oxygen outlet port and the chlorine outlet port.