There are provided processes for preparing lithium hydroxide that comprise submitting an aqueous composition comprising a lithium compound to an electrolysis or an electrodialysis under conditions suitable for converting at least a portion of the lithium compound into lithium hydroxide. For example, the lithium compound can be lithium sulphate and the aqueous composition can be at least substantially maintained at a pH having a value of about 1 to about 4.

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.

Provided is an operation support apparatus comprising: a production efficiency acquisition unit which acquires production efficiency of an electrolysis tank; a determination unit which determines whether the production efficiency of the electrolysis tank acquired by the production efficiency acquisition unit is below a predetermined production efficiency threshold value; and an identification unit which identifies, if it is determined by the determination unit that the production efficiency of the electrolysis tank is below the production efficiency threshold value, a first factor for which the production efficiency of the electrolysis tank has fallen below the production efficiency threshold value.

Provided is an operation support apparatus comprising: a production efficiency acquisition unit which acquires production efficiency of an electrolysis tank; a determination unit which determines whether the production efficiency of the electrolysis tank acquired by the production efficiency acquisition unit is below a predetermined production efficiency threshold value; and an identification unit which identifies, if it is determined by the determination unit that the production efficiency of the electrolysis tank is below the production efficiency threshold value, a first factor for which the production efficiency of the electrolysis tank has fallen below the production efficiency threshold value.

A brine electrolysis system for producing pressurized chlorine and hydrogen gases. In its basic configuration, the brine electrolysis system may comprise: two liquid storage tanks for storing two liquid reactants; a tank having two interior spaces separated by a diaphragm for receiving the liquid reactants; two pumps for regulating the flow of the liquid reactants from the liquid storage tanks to the interior spaces of the tank, two open-bottom cylinders for storing and dispensing two gases; an electrolysis stack assembly for converting the liquid reactants into two gases; and two submersible pumps for pumping each liquid reactant into an electrolysis stack assembly. Each open-bottom cylinder may comprise a float sensor for determining the amount of fluid entering its cylindrical space. The system may further comprise controllers for regulating ionic concentrations within the two interior spaces. Dispense lines and valves may be utilized to release the gases.

A neutralization cell is provided which may be used to increase a pH level of a chlorine solution. The neutralization cell includes a neutralization anode, a neutralization cathode, an inlet, and an outlet. The neutralization anode and the neutralization cathode are positioned to divide the neutralization cell into a middle area between the neutralization anode and the neutralization cathode, an anode area on a side of the neutralization anode furthest from the neutralization cathode, and a cathode area on a side of the neutralization cathode furthest from the neutralization anode. The inlet directs the chlorine solution into the neutralization cell by directing an incoming flow of the chlorine solution into the anode area. The outlet directs the chlorine solution out of the neutralization cell by directing an outgoing flow of the chlorine solution from the cathode area.

A method of operating an electrochemical cell including introducing an aqueous solution into the electrochemical cell, applying a current across an anode and a cathode to produce a product, monitoring the voltage, dissolved hydrogen, or a condition of the aqueous solution, and applying the current in a pulsed waveform responsive to one of the measured parameters is disclosed. An electrochemical system including an electrochemical cell including an anode and a cathode, a source of an aqueous solution having an outlet fluidly connectable to the electrochemical cell, a sensor for measuring a parameter, and a controller configured to cause the anode and the cathode to apply the current in a pulsed waveform responsive to the parameter measurement is disclosed. Methods of suppressing accumulation of hydrogen gas within the electrochemical cell are also disclosed. Methods of facilitating operation of an electrochemical cell are also disclosed.

An electrochemical cell including a first chamber having an anode, a second chamber having a cathode, at least one ionic connection between the first chamber and the second chamber, such that liquid electrolyte from the first chamber is prevented from mixing with liquid electrolyte in the second chamber is provided. The first chamber and the second chamber can be arranged in parallel and positioned remotely from each other. An electrochemical system including the electrochemical cell, and first and second sources of saline aqueous solutions is also provided. Water treatment systems are also provided. A method of operating an electrochemical cell including introducing first and second saline aqueous solutions into first and second chambers of the electrochemical cell, and applying a current across the anode and the cathode to generate first and second products, respectively is also provided. A method of facilitating operation of an electrochemical cell is also provided.

Disclosed herein is a spatially decoupled redox flow water electrolyzer, that has a hydrogen-producing catholyte section formed from a catholyte tank, having a cathode, and a hydrogen generation compartment, where the catholyte tank and the hydrogen generation compartment are fluidly connected to one another by a fluid pathway, so as to facilitate the circulation of a liquid catholyte from the catholyte tank to the hydrogen generation compartment and back to the catholyte tank and an oxygen-producing anolyte section formed from an anolyte tank, having an anode, and an oxygen producing compartment, where the anolyte tank and the oxygen producing compartment are fluidly connected to one another by a fluid pathway, so as to facilitate the circulation of a liquid anolyte from the anolyte tank to the oxygen producing compartment and back to the anolyte tank, an anion-exchange membrane is disposed between the catholyte and anolyte tanks and a current collector attached to the catholyte and anolyte tanks. In use, the hydrogen generation compartment contains a catalyst capable of catalysing hydrogen production when brought into contact with a cathodic redox mediator when the cathodic redox mediator is in a reduced state and the oxygen generation compartment contains a catalyst capable of catalysing oxygen production when brought into contact with an anodic redox mediator when the anodic redox mediator is in an oxidised state.

Disclosed herein is a spatially decoupled redox flow water electrolyzer, that has a hydrogen-producing catholyte section formed from a catholyte tank, having a cathode, and a hydrogen generation compartment, where the catholyte tank and the hydrogen generation compartment are fluidly connected to one another by a fluid pathway, so as to facilitate the circulation of a liquid catholyte from the catholyte tank to the hydrogen generation compartment and back to the catholyte tank and an oxygen-producing anolyte section formed from an anolyte tank, having an anode, and an oxygen producing compartment, where the anolyte tank and the oxygen producing compartment are fluidly connected to one another by a fluid pathway, so as to facilitate the circulation of a liquid anolyte from the anolyte tank to the oxygen producing compartment and back to the anolyte tank, an anion-exchange membrane is disposed between the catholyte and anolyte tanks and a current collector attached to the catholyte and anolyte tanks. In use, the hydrogen generation compartment contains a catalyst capable of catalysing hydrogen production when brought into contact with a cathodic redox mediator when the cathodic redox mediator is in a reduced state and the oxygen generation compartment contains a catalyst capable of catalysing oxygen production when brought into contact with an anodic redox mediator when the anodic redox mediator is in an oxidised state.