Abstract: The invention relates to a method for carrying out a chemical reaction, in particular for carrying out a gas-gas or gas-ions reaction, in which, in the absence of a substance catalytically active for the corresponding chemical reaction, an educt or educts is(are) introduced between at least two electric conductors, as well as at the electric conductors an optionally adjustable voltage is applied, through the electric field generated in this way the chemical reaction is initiated and/or the rate of the chemical reaction is increased as well as allowed to proceed and the substance quantity of the product(s) formed is maintained non-proportional to a charge quantity optionally flowing between the electric conductors.

Abstract: The invention relates to an electrolysis device, comprising at least one horizontal electrolytic cell with a housing (6) and an anode (8) that has a membrane or a diaphragm (18), and a cathode (9) that has a gas diffusion electrode (17). The device further comprises supply (21) and discharge (23) means for gas (3) which lead to or away from the gas chamber (22) of the cathode (9), and supply (16; 19) and discharge (16; 20) means for electrolytes (1) which lead to or away from the first electrolytic chamber (4) and to or away from the second electrolytic chamber (5). The anode (8) and the membrane or the diaphragm (18) have at least one respective opening for the supply (19) of electrolytes (1) to the second electrolytic chamber (5), and at least one one further opening for the discharge (20) of electrolytes from the second electrolytic chamber.

Abstract: The invention relates to an electrolyte cell with an end anode and an end cathode and bipolar cell elements disposed between outer cell elements comprising these and electrically connected with them and connected in series one with the other, wherein each cell element comprises one or two gas diffusion electrode(s) of which one forms simultaneously the ceiling of the subjacent electrolyte chamber and the floor of the superjacent electrolyte chamber and the end anode and the anodes of the bipolar cell elements comprise a perforated, electrically well-conducting electrode structure, wherein each electrolyte chamber is charged with electrolyte and reaction gas, such as oxygen, and a particular mixture of electrolyte and the resulting product as well as residual reaction gas are drawn off from each electrolyte chamber, wherein the cell elements are combined in the form of a stack, that [sic] the end cathode and the cathodes of the bipolar cell elements comprise a perforated, electrically well-conducting support w

Abstract: An electrolytic cell comprising bipolar electrodes is employed for electrochemical deposition of copper, zinc, lead, nickel or cobalt. An interior space is provided between the cathode side and the anode side of a bipolar electrode. The electrolyte can flow substantially without an obstruction through the interelectrode space between adjacent electrodes. The current densities in the interelectrode space amount to 800 to 8000 A/m.sup.2. Gas is evolved on the anode side of the bipolar electrodes and causes liquid to flow along the anode side. In the middle of the height of the anode side that liquid flow has a vertical component having a velocity of 5 to 100 cm/second. Electrolyte solution flows from the upper edge portion of the anode side to a return flow space, in which the solution flows downwardly. From the return flow space the solution is returned to the lower portion of the interelectrode space.

Abstract: The anode comprises a substantially horizontal carrying bar, which is disposed outside the electrolyte and serves to supply electric current. Two substantially parallel metal surfaces (anode grids) are electrically conductively connected to the carrying bar and with at least one-half of their surface extending into the electrolyte. The carrying bar comprises a copper conductor, to which at least one vertical copper rod is joined. There is a direct electrically conducting connection between the copper conductor and the copper rod. The copper rod is surrounded by a titanium sheath and is an interference fit in that sheath. The copper rod provided with the titanium sheath is disposed between the two anode grids and is electrically conductively connected to said grids.

Abstract: The ammonium polysulfide is produced in at least one electrochemical cell, to which an aqueous ammonium sulfide solution is supplied as electrolyte. The cell comprises an anode, a gas diffusion cathode, and between the anode and the cathode an electrolyte chamber, where the cell voltage is 0.01 to 5V. The cathode has an electrically conductive, gas-permeable carbon layer, over which flows gas containing free oxygen, and which is in contact with the electrolyte. O.sub.2 -containing gas is introduced into the electrolyte chamber, thereby forming hydroperoxide anions (OOH.sup.-) in the electrolyte chamber. From the electrolyte chamber a solution containing ammonium polysulfide and a residual gas are withdrawn.

Abstract: The aqueous alkali chloride solution is coarsely purified first. In the succeeding fine purifier the solution, which contains calcium ions, magnesium ions and undissolved magnesium compounds, is passed through a plurality of purification stages (ion exchange stages), which contain cation exchange granulate. In the fine purifier the solution having a pH value of about 10 to 11 is passed through a first ion exchange stage and the solution coming from the first ion exchange is acidified to decrease its pH value by at least 0.5. The solution is subsequently passed through at least one second ion exchange stage and a solution which is virtually free of undissolved magnesium compounds is withdrawn from the fine purification means. The acidified solution fed to the second ion exchange stage has preferably a pH value of 5 to 10.

Abstract: For the production of a gaseous mixture contains chlorine dioxide and chlorine, alkali chlorate in an aqueous solution with acid is reacted in a reactor. The reactor comprises a plurality of superimposed reaction levels which are traversed by the solution from top to bottom. In the lower portion of the reactor the solution in which chlorate and acid have been depleted is reboiled in a reboiling chamber by an indirect heating at a temperature in the range from 100.degree. to 110.degree. C. The depleted solution is conducted from the reboiling chamber to a pressure chamber, in which a pressure of at least 1.2 bar is maintained. In the pressure chamber the solution is reboiled at temperatures from 110.degree. to 150.degree. C. and the vapors formed by the reboiling in the pressure chamber are conducted through the reboiling chamber for an indirect heating therein.

Abstract: Chlorine dioxide is increasibly used to bleach pulp and the like. Chlorine dioxide is produced in a reactor, which contains a plurality of superimposed bubble cap trays, which are provided with passages for the gas and with duct, which is independent of the gas passages and serves as an overflow for the liquid. In order to maintain a maximum ClO.sub.3 /acid ratio for the longest time possible, the reaction chamber above each bubble cap tray is divided into a large number of reaction compartments by vertical partitions, which define openings for the passage of the reaction liquid. Acid can be supplied to each compartment. The partitions can be used to define in each reaction chamber any desired number of reaction compartments, which are connected in parallel for the flow of acid and are connected in series for the flow of the chlorate solution.

Abstract: Alkali hydroxide, chlorine and hydrogen are produced from an aqueous alkali chloride solution by membrane electrolysis. A high-NaCl solid salt, which contains impurities, is dissolved in water in a salt dissolver. Precipitating chemicals are added to the salt solution to precipitate the impurities. The resulting mixture is fed to a thickener, from which precipitates and clarified raw brine are separately withdrawn. The clarified raw brine from the thickener is divided at a ratio between 2:1 and 20:1 into first and second partial streams. The larger first partial stream is mixed with the salt solution and the precipitating chemicals before entering the thickener and the resulting mixture is fed to the thickener. The second partial stream of the clarified raw brine is fed through a fine purifier to the electrolytic cell. Spent brine from the electrolytic cell is fed to the salt dissolver.

Abstract: In an electrode assembly for gas-forming electrolyzers, particularly for monopolar membrane electrolyzers comprising vertical plate electrodes and opposite electrodes and a membrane between the plate electrode and the opposite electrode, the distribution of current in the membrane is improved and the voltage drop is decreased in that the plate electrodes are provided on that surface which faces the membrane with ante-electrodes, which consist of apertured, electrically conducting surface structures, which are electrically conductively connected to the plate electrodes and extend in planes which are parallel to the plate electrodes.

Abstract: In an electrolytic cell having a membrane and vertical electrodes composed of a plurality of units,a. the electrode having one polarity is horizontally divided into a plurality of units,b. the electrode having the opposite polarity is vertically divided into a plurality of units, andc. the units of at least one of the two electrodes are adapted to be displaced by spring elements. Spacers are suitably provided between the units of that electrode which is not contacted by the membrane.

Abstract: In gas-forming electrolyzers, particularly membrane electrolyzers having vertically extending plate electrodes, each electrode plate is divided into horizontal strips and the entire active electrode surface is parallel to the counterelectrode and spaced from it as closely as possible. The top portions of each of the horizontal strips into which the electrode is divided define gas escape paths and extend away from the counterelectrode. To improve the degassing of the electrolyte the ratio of the distance G between the counterelectrode or membrane and the gas-defining line S at the lower edge of each electrode strip to the distance E between the counterelectrode or membrane and the breakaway edge K of the angled portion defining the gas escape path corresponds to a degassing capability F which is lower than 0.6.

Abstract: This invention relates to a process of producing oxyacids of chlorine or salts of such acids by an electrolysis of salt solutions which are contaminated with calcium and/or magnesium or of sea water. In such processes, deposits or crusts are formed on the electrodes in the course of time, particularly in the cells to which the sea water is supplied first. For this reason, the plant must be cleaned from time to time. By means of the invention, a formation of crusts is virtually prevented in that the electrolysis is carried out(a) in an initial phase with an electrolyte flowing at a velocity above 0.7 meter per second and up to 2.0 meters per second and(b) in a succeeding phase with an electrolyte flowing at a velocity of 0.3 meter per second to less than 0.7 meter per second,the velocity of flow being stated for electrolyte which is free from gas.

Abstract: In electrolytic apparatus comprising cell chambers through which is passed an electrolyte and in which sets of anode plates are provided, each of which are connected to current-feeding center pins, and the mutually staggered electrode plates protrude into the gaps between plates having the opposite polarity. To ensure a simple, quick and reliable installation and removal of the anode plates, the center pin is provided with contact straps, which are spaced apart in the longitudinal direction of the pin and serve to secure the anode plate. The contact straps are suitably spaced about 180.degree. apart and have at least one opening, which consists preferably of a tapped bore.The electrolytic apparatus is used in processes of producing alkali chlorate by the electrolytic decomposition of aqueous alkali chloride solutions.

Abstract: In the continuous production of chlorine dioxide wherein an alkali metal chlorate solution is reacted with hydrochloric acid in a reactor through which an air stream is passed countercurrent to the alkali metal chlorate solution, and there discharged from the reactor chlorine dioxide and alkali metal chloride solution, the improvement which comprises including chlorine gas in the air stream, thereby permitting the overall efficiency of the process to be increased at a given content of chlorine dioxide in the gas discharged from the reactor.

Abstract: This invention relates to a process of producing oxyacids of chlorine or salts of such acids by an electrolysis of salt solutions which are contaminated with calcium and/or magnesium or of sea water. In such processes, deposits or crusts are formed on the electrodes in the course of time, particularly in the cells to which the sea water is supplied first. For this reason, the plant must be cleaned from time to time. By means of the invention, a formation of crusts is virtually prevented in that the electrolysis is carried out(a) in an initial phase with an electrolyte flowing at a velocity above 0.7 meter per second and up to 2.0 meters per second and(b) in a succeeding phase with an electrolyte flowing at a velocity of 0.3 meter per second to less than 0.7 meter per second,the velocity of flow being stated for electrolyte which is free from gas.

Abstract: A process for the production of chlorine dioxide by membrane electrolysis of aqueous sodium chloride, reaction of hydrogen and chlorine so-formed to form hydrogen chloride and reaction of the so-formed hydrogen chloride with the sodium chlorate also formed by the electrolysis to form chlorine dioxide is disclosed. Also disclosed is the production of chlorine by such a process.

Abstract: In the manufacture of sheet metal elements or strip having a catalytic surface structure, a mixture of skeleton material powder, and of Raney alloy powder is rolled onto the starting sheet metal element or strip substrate, sintered in a reducing atmosphere, whereafter the soluble component of the Raney alloy is dissolved out.To ensure an adequate adherence of the catalytic surface structure, the operation in which the above-mentioned mixture is rolled onto the substrate is accompanied by a simultaneous cold-working of the substrate with a deformation of 20 to 60% within each cold-forming step.The coated sheet metal element or strip substrates or any spherical bodies made therefrom serve as electrodes in electrolytic processes.

Abstract: An improvement in a process of electrolyzing an aqueous solution of an alkali metal halide in a membrane cell in which a pH above 1.0 is maintained in the anode chamber, the alkali metal halide solution is removed from the anode chamber and its concentration and pH are increased is described. The improvement resides in thereafter decreasing the pH of at least a portion of the resultant solution to below 1.0 and thereafter adjusting the pH to 1.0 to 6.0 and returning the so adjusted solution to the anode chamber.