Abstract: The present invention relates to a method of redissociating Michael adducts of acrylic acid present in a liquid F in a redissociation apparatus comprising at least one separating column K, an evaporator V and a pump P, wherein, in the event of an unwanted rise in the viscosity of the residue R in the bottom space of the separating column K, the feed of the liquid F into the redissociation apparatus is stopped, the residue R in the bottom space of the separating column K is diluted and cooled with a solvent 1, and the bottom space of the separating column K is emptied.

Abstract: An electrode unit for an electrochemical device, comprising (i) a solid electrolyte which divides a space for molten cathode material, selected from the group consisting of elemental sulfur and polysulfide of the alkali metal anode material, and a space for molten alkali metal anode material, and (ii) a porous solid state electrode directly adjacent to the solid electrolyte within the space for the cathode material, with a non-electron-conducting intermediate layer S present between the solid state electrode and the solid electrolyte, wherein this intermediate layer S has a thickness in the range from 0.

Abstract: Provided herein is an apparatus for storing electric energy including at least one electrochemical cell having an anode space and a cathode space that are separated by a solid electrolyte, a first store for anode material that is connected to the anode space, and a second store for cathode material that is connected to the cathode space. The cathode space is also connected to a third store. The second and third stores are connected to one another by means of a gas conduit that opens into the upper region of the second and third stores. A conveying apparatus for gas having a reversible conveying direction is accommodated in the gas conduit. Further provided herein is a method of operating the apparatus.

Abstract: Provided herein is an apparatus for storing electric energy including at least one electrochemical cell having an anode space and a cathode space that are separated by a solid electrolyte, a first store for anode material that is connected to the anode space, and a second store for cathode material that is connected to the cathode space. The cathode space is also connected to a third store. The second and third stores are connected to one another by means of a gas conduit that opens into the upper region of the second and third stores. A conveying apparatus for gas having a reversible conveying direction is accommodated in the gas conduit. Further provided herein is a method of operating the apparatus.

Abstract: The invention relates to an electrode unit for an electrochemical device, comprising a solid electrolyte (3) and a porous electrode (7), the solid electrolyte (3) dividing a compartment for cathode material and a compartment for anode material and the porous electrode (7) being extensively connected to the solid electrolyte (3), with a displacer (23) being accommodated in the anode material compartment, where the displacer (23) is manufactured from a stainless steel or from graphite foil and bears resiliently against the internal geometry of the solid electrolyte (3) in such a way that the displacer (23) does not contact the solid electrolyte over its full area, or with the displacer comprising an outer shell (62) of stainless steel or graphite, and a core (64) of a nonferrous metal, the nonferrous metal being thermoplastically deformable at a temperature which is lower than the temperature at which the stainless steel is thermoplastically deformable, and where for production the shell (62) of stainless steel

Abstract: An electrode unit for an electrochemical device, comprising (i) a solid electrolyte which divides a space for molten cathode material, selected from the group consisting of elemental sulfur and polysulfide of the alkali metal anode material, and a space for molten alkali metal anode material, and (ii) a porous solid state electrode directly adjacent to the solid electrolyte within the space for the cathode material, with a non-electron-conducting intermediate layer S present between the solid state electrode and the solid electrolyte, wherein this intermediate layer S has a thickness in the range from 0.

Abstract: The present invention relates to sodium oxygen cells comprising (A) at least one anode comprising sodium, (B) at least one gas diffusion electrode comprising at least one porous support, and (C) a liquid electrolyte comprising at least one aprotic glycol diether with a molecular weight Mn of not more than 350 g/mol. The present invention further relates to the use of the invention sodium oxygen cells and to a process for preparing sodium supperoxide of formula NaO2.

Abstract: The present invention relates to sodium oxygen cells comprising (A) at least one anode comprising sodium, (B) at least one gas diffusion electrode comprising at least one porous support, and (C) a liquid electrolyte comprising at least one aprotic glycol diether with a molecular weight Mn of not more than 350 g/mol. The present invention further relates to the use of the invention sodium oxygen cells and to a process for preparing sodium supperoxide of formula NaO2.

Abstract: The invention relates to an electrode unit for an electrochemical device, comprising a solid electrolyte (3) and a porous electrode (7), the solid electrolyte (3) dividing a compartment for cathode material and a compartment for anode material and the porous electrode (7) being extensively connected to the solid electrolyte (3), with a displacer (23) being accommodated in the anode material compartment, where the displacer (23) is manufactured from a stainless steel or from graphite foil and bears resiliently against the internal geometry of the solid electrolyte (3) in such a way that the displacer (23) does not contact the solid electrolyte over its full area, or with the displacer comprising an outer shell (62) of stainless steel or graphite, and a core (64) of a nonferrous metal, the nonferrous metal being thermoplastically deformable at a temperature which is lower than the temperature at which the stainless steel is thermoplastically deformable, and where for production the shell (62) of stainless steel

Abstract: Process for preparing an alkali metal from a salt of the alkali metal which is soluble in a solvent, including a first electrolysis, a concentration, and a second electrolysis. The first electrolysis produces a product mixture. This product mixture is then concentrated to give a largely solvent-free alkali metal (poly)sulfide melt. A second electrolysis at a temperature above the melting point of the alkali metal is then performed in a second electrolysis cell comprising an anode space and a cathode space, separated by a solid electrolyte which conducts alkali metal cations. The alkali metal (poly)sulfide melt from the concentration step is fed to the anode space. Sulfur is removed from the anode space and liquid alkali metal is removed from the cathode space.

Abstract: The invention relates to an electrode unit for an electrochemical device for storing electrical energy, comprising a solid electrolyte (3) and a porous electrode (7), the solid electrolyte (3) dividing a compartment for cathode material and a compartment for anode material and the porous electrode (7) being extensively connected to the solid electrolyte (3) and the cathode material flowing along the porous electrode (7) during discharging. On the side remote from the solid electrolyte (3), the porous electrode (7) is covered towards the compartment for the cathode material with a segment wall (9), the segment wall (9) comprising inlet openings (15) in the direction of flow of the cathode material, through which the cathode material penetrates into the porous electrode (7), reacts chemically with the anode material in the porous electrode (7) and emerges back out of the porous electrode (7) through outlet openings (17) downstream in the direction of flow.

Abstract: A process for preparing aluminum oxide with a low calcium content, in which (1) crude alpha- and/or gamma-aluminum oxide with a total calcium content in the range from 50 to 2000 ppm, based on the crude alpha- and/or gamma-aluminum oxide, is mixed with an aqueous solution or suspension comprising the compounds selected from the group of inorganic acid, organic acid and complexing agent, (2) the mixture from step (1) is admixed with a flocculating aid, (3) in the mixture of step (2), the solids are separated from the liquid, (4) the solids separated are mixed with water in the presence or in the absence of a flocculating aid, (5) in the mixture of step (4), the solids are separated from the liquid, (6) optionally, steps (4) and (5) are repeated once or more than once, (7) optionally, the solids separated optionally after addition of further compounds, are dried.

Abstract: A process for preparing aluminum oxide with a low calcium content, in which (1) crude alpha- and/or gamma-aluminum oxide with a total calcium content in the range from 50 to 2000 ppm, based on the crude alpha- and/or gamma-aluminum oxide, is mixed with an aqueous solution or suspension comprising the compounds selected from the group of inorganic acid, organic acid and complexing agent, (2) the mixture from step (1) is admixed with a flocculating aid, (3) in the mixture of step (2), the solids are separated from the liquid, (4) the solids separated are mixed with water in the presence or in the absence of a flocculating aid, (5) in the mixture of step (4), the solids are separated from the liquid, (6) optionally, steps (4) and (5) are repeated once or more than once, (7) optionally, the solids separated optionally after addition of further compounds, are dried.

Abstract: A process for preparing magnesium compounds by precipitation, in which an aqueous solution or suspension of a magnesium compound is mixed with a precipitant and the corresponding magnesium compound is precipitated wherein the aqueous solution or suspension of a magnesium compound is obtained by reaction of an organomagnesium compound with an aldehyde or a ketone or another electrophile and subsequent aqueous workup of the reaction mixture at a pH of at most 10 or from a magnesium salt with a maximum calcium content and/or potassium content of 200 ppm, based on the magnesium salt used.