A composite membrane that is suitable for use in a molten alkaline water electrolyzer. In one embodiment, the composite membrane includes a porous support, the porous support being in the form of a matrix of metal oxide particles randomly arranged to form a plurality of tortuous pores. The composite membrane also includes molten electrolyte filling the pores of the porous support, the molten electrolyte having hydroxide ion conductivity. The molten electrolyte may be a single species of an alkali hydroxide or of an alkaline earth hydroxide. Alternatively, the molten electrolyte may be a eutectic or non-eutectic mixture of two or more species of alkali hydroxides or alkaline earth hydroxides. The composite membrane may further include one or more additives, such as a coarsening inhibitor, a crack attenuator, and a reinforcing material. The composite material may be used to make a molten alkaline membrane water electrolyzer with high electrical efficiencies.

A method for operating a water electrolysis device for produces hydrogen and oxygen from water. A throughflow direction is reversed by way of a suitable activation of valves (17, 18) in order to increase a service life of a PEM electrolyzer (1). This is effected periodically such that an equal throughflow in both directions is effected, by which the service life is increased.

A method is for producing seals on faces of electrochemical reactor components intended to be stacked in order to form an electrochemical reactor Each component is in the form of a plate and having a first face and an opposing second face. The first face is designed to receive a first seal and the second face is designed to receive a second seal. The method includes shaping the first seals on the first faces of the components, the first seals being at least partially polymerized; depositing the second seals on the second face of the components; and shaping the second seals by compressing a stack formed from the components alternating with molding plates. Each molding plate has a bearing face pressed against the first face of a component and includes a groove designed to receive, without deforming, the first seal previously formed on the first face of said component, and a molding face pressed against the second face of another component and having a molding surface for shaping the second seal deposited on the second face of said other component as a result of compressing the stack. The method also includes at least partially polymerizing the second seals.

The disclosure relates to methods for preparing lithium hydroxide. For example, such methods can comprise mixing a lithium-containing material with an acidic aqueous composition optionally comprising lithium sulfate and thereby obtaining a mixture; roasting the mixture under suitable conditions to obtain a roasted, lithium-containing material; leaching the roasted material under conditions suitable to obtain a first aqueous composition comprising lithium sulfate; submitting the first aqueous composition comprising lithium sulfate to an electromembrane process under suitable conditions for at least partial conversion of the lithium sulfate into lithium hydroxide and to obtain a second aqueous composition comprising lithium sulfate, the electromembrane process involving a hydrogen depolarized anode; optionally increasing concentration of acid in the second aqueous composition; and using the second aqueous composition comprising lithium sulfate as the acidic aqueous composition optionally comprising lithium sulfate for mixing with the lithium-containing material and to obtain the mixture.

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.

An electrochemical reaction device in an embodiment includes: a reaction unit including a first accommodation part to accommodate carbon dioxide and a second accommodation part to accommodate an electrolytic solution containing water; a reduction electrode to reduce the carbon dioxide; an oxidation electrode to oxidize the water; a power supply to pass current between the reduction electrode and the oxidation electrode; a pressure regulator to regulate a pressure in the first accommodation part; a reaction product detector to detect at least one of an amount and a kind of a substance produced at the reduction electrode; and a controller to control the pressure regulator based on a detection signal of the reaction product detector.

An electrochemical cell has a membrane located between two flow field plates. On a first side of the membrane, there is a porous support surrounded by a seal between the membrane and the flow field plate. There is a gap between the porous support and the seal at the surface of the membrane. On a second side of the membrane, there is a seal between the membrane and the flow field plate located inside of the gap in plan view. The electrochemical cell is useful, for example, in high pressure or differential pressure electrolysis in which the second side of the membrane will be consistently exposed to a higher pressure than the first side of the membrane.

Provided are an electrode for electrolysis having excellent durability against reverse current, and a method that enables production of the electrode for electrolysis at low cost. The electrode for electrolysis 130 includes a conductive substrate 132 on which a catalyst layer is formed, and a reverse current absorption body 134 that is coupled to the conductive substrate 132 in a detachable manner, wherein the reverse current absorption body 134 is formed from a sintered compact containing nickel. The method for producing the electrode for electrolysis 130 includes a sintered compact formation step of obtaining the sintered compact by sintering a raw material powder composed of any one of Raney nickel alloy particles containing nickel and an alkali-soluble metal element, metallic nickel particles, and a mixture of Raney nickel alloy particles and metallic nickel particles, and a coupling step of coupling the sintered compact to the conductive substrate 132.

Systems and methods for generating reactive oxygen species formulations useful in various oxidation applications. Exemplary formulations include singlet oxygen or superoxide and can also contain hydroxyl radicals or hydroperoxy radicals, among others. Formulations can contain other reactive species, including other radicals. Exemplary formulations containing peracids are activated to generate singlet oxygen. Exemplary formulations include those containing a mixture of superoxide and hydrogen peroxide. Exemplary formulations include those in which one or more components of the formulation are generated electrochemically. Formulations of the invention containing reactive oxygen species can be further activated to generate reactive oxygen species using activation chosen from a Fenton or Fenton-like catalyst, ultrasound, ultraviolet radiation or thermal activation. Exemplary applications of the formulations of the invention among others include: cleaning in place applications, water treatment, soil decontamination and flushing of well casings and water distribution pipes.

Disclosed herein are ion exchange membranes, electrochemical systems, and methods that relate to various configurations of the ion exchange membranes and other components of the electrochemical cell.