An electro-chemical activation (ECA) system includes an anode chamber, a cathode chamber, and a neutralization chamber. The anode chamber includes an anode configured to convert water having an alkaline-metal chloride into an anodic electrolyte that includes hypochlorous acid. The cathode chamber includes a cathode configured to convert water into a cathodic electrolyte. The neutralization chamber includes a neutralization cathode configured to remove protons from the anodic electrolyte after it leaves the anode chamber. The ECA system is configured to recirculate the anodic electrolyte back through the anode chamber and the neutralization chamber at least one more time to produce a concentrated chlorine solution. The ECA system is further configured to recirculate the cathodic electrolyte back through the cathode chamber at least one additional time to produce a concentrated alkaline solution.

In an aspect a method of recovering hydrogen, the method comprises reacting a hydrocarbon to form a carbon compound and hydrogen in the presence of a catalyst, wherein the carbon compound comprises at least one of carbon dioxide or carbon monoxide; separating the carbon compound from the hydrogen; directing the carbon compound to a cathode side of an electrochemical cell and directing water to an anode side of the electrochemical cell; electrolyzing the water on the anode side to form oxygen and protons; applying a voltage to a membrane and electrode assembly in the electrochemical cell to cause the protons to traverse through a proton exchange membrane from an anode to a cathode on the cathode side; and reacting the protons with the carbon compound to form an organic product.

A method for making an aqueous hypochlorous acid (HClO) solution includes electrolyzing a solution of sodium chloride to produce a solution of sodium hypochlorite; and producing the aqueous hypochlorous acid solution by adjusting a pH of the solution of sodium hypochlorite to a value within a range of 3 to 8 by adding a selected weak acid to the solution of sodium hypochlorite to produce a buffer including the selected weak acid and a salt of the selected weak acid.

A system optionally including a carbon oxide reactor. A method for carbon oxide reactor control, optionally including selecting carbon oxide reactor aspects based on a desired output composition, running a carbon oxide reactor under controlled process conditions to produce a desired output composition, and/or altering the process conditions to alter the output composition.

CO.sub.2 reaction methods may include: supplying CO.sub.2-containing gas to a first accommodation part (AP) of an electrochemical reaction cell (ERC) from a first supply unit, the ERC including the first AP, a second AP, a cathode in the first AP, and an anode in the second AP; supplying an electrolytic solution containing H.sub.2O to the second AP; controlling ERC temperature to 60 to 150° C. so discharged gas and discharged solution discharged from the first and second APs are 60 to 100° C.; supplying current to the electrodes, reducing the CO.sub.2 at the reduction electrode and discharge gas from the first AP, and oxidizing H.sub.2O and discharge the solution containing O.sub.2 and CO.sub.2 from the second AP; separating O.sub.2 and CO.sub.2 gas from the discharged solution; combusting the O.sub.2 to produce CO.sub.2, and discharging mixed-CO.sub.2 gas containing combustion CO.sub.2 and CO.sub.2; and supplying the mixed-CO.sub.2 gas to the first AP.

A system for producing gas streams for use in synthetic fuel production through CO2 capture and water splitting is disclosed. The system includes a CO2 capture device configured to receive a CO2-containing stream and including an aqueous alkaline solution. The alkaline solution includes hydroxide and/or carbonate ions. The CO2 capture device generates a carbon-rich solution when the alkaline solution absorbs CO2. The carbon-rich solution includes carbonate and/or bicarbonate ions. The system also includes an electrolyzer fluidically coupled to the CO2 capture device, and defining a volume including an anode region having an anode, and a cathode region having a cathode. The volume includes an electrolyte solution having a pH gradient generated by an electric current, causing the electrolyte solution to be acidic in the anode region and alkaline in the cathode region. The carbon-rich solution is received into the electrolyzer. The electrolyzer generates hydrogen, oxygen, and CO2 streams.

An electrochemical reaction device of an embodiment includes: an electrochemical reaction cell 1 that includes: a first electrode having a first flow path, a second electrode having a second flow path, and a separating membrane sandwiched between the first electrode and the second electrode; a liquid tank that contains a liquid to be treated supplied to the second flow path of the second electrode; a first pipe that connects an inlet of the second flow path and the liquid tank; a second pipe that connects an outlet of the second flow path and the liquid tank; and a backflow suppression mechanism that is provided in the second pipe to prevent backflow of the liquid to be treated flowing in the second pipe or reduce a backflow speed.

An electrolysis system includes: an oxygen consumption device that consumes, using hydrogen, oxygen gas in exhaust gas; a valve device that is configured to switch a supply destination of the hydrogen-containing gas output from a solid oxide electrolysis stack to either one of the oxygen consumption device or a generating device; and a control device that controls the valve device according to the oxygen concentration in the exhaust gas output from the oxygen consumption device to switch the supply destination of the hydrogen-containing gas.

Device for obtaining electrolysis products from an alkali metal chloride solution where a cathode circuit contains a circulation pump with an overflow device for the return flow of pump liquid, which continuously secures the forced circulation of the catholyte via a heat exchanger, a cathode compartment and a capacitive separator for separating the hydrogen from the catholyte. In the discharge of the hydrogen from the capacitive separator for separation of the hydrogen from the catholyte, a cooled humidity separator is installed, the condensate collection container of which is connected via a dosage pump with the freshwater feed to the mixing device of the freshwater flow with the gaseous oxidant mixture.

A method includes providing raw water into a first filter assembly to remove solids from the raw water to form a filtrate, providing the filtrate from the first filter assembly into a second filter assembly to electrochemically remove ionics from the filtrate to form purified water, and providing the purified water to an electrolyzer to generate hydrogen by electrolyzing the purified water.