Abstract: A method for determining the concentration of a plurality of combustible gases in a gas stream comprises providing an electrochemical cell apparatus that includes an electrochemical cell in which a cavity is formed having a diffusion limiting port forming the entrance to the cavity. The cell has a process side in flow communication with a portion of the gas stream flowing into the cavity through the port, and a reference side in flow communication with a reference gas. The process side and the reference side of the electrochemical cell are separated by an electrolyte. The potential difference across the cell is adjusted to create a steady state electrical current flow.

Abstract: There is disclosed a plate-, foil- or web-shaped support material for offset printing plates, made of mill-finished, mechanically and/or chemically or mechanically and electrochemically grained aluminum or an aluminum alloy, which has been anodized in aqueous-alkaline solutions. The support material of the invention shows a reflectometer value, at an angle of incidence of 60.degree. (measured according to DIN 67 530; 1982), of greater than 5, an abrasion of the oxide layer of less than 0.5 g/m.sup.2 and a resistance to alkali of greater than 140 s. Also disclosed is a process for the manufacture of the support material, in which an anodic oxidation is carried out in an electrolyte having a pH greater than or equal to 12.5, at a voltage of less than 50 V.

Abstract: A recovery process is disclosed for reclaiming the lithium content from aluminum-lithium alloy scrap including establishing a three-layered electrolytic cell comprising a most dense lowest layer of molten aluminum-lithium alloy, a middle layer of molten salt electrolyte, and an uppermost layer of molten aluminum-lithium; maintaining the lowest layer of molten aluminum-lithium alloy at a positive DC voltage with respect to the uppermost layer of molten lithium; establishing a current flow through the cell; establishing a specified composition in the molten salt electrolyte such that lithium in the lowest layer is electrochemically oxidized and passes into the molten salt electrolyte as lithium ions and further such that said lithium ions are electrochemically reduced and pass into the uppermost layer as lithium metal; and withdrawing lithium from the uppermost layer.

Abstract: Electrolytic processes for the growth of single crystal tin or other elemental crystals, with or without the use of a substrate. Exemplified cubic forms of alpha-tin and tetragonal forms of beta-tin are grown using a shaped anode and a pointed cathode to provide electrical geometric fields within an electrodeposition system to enhance the growth of the desired crystalline tin.

Abstract: An electrolytic cell which is preferably of the filter press type and which comprises at least one anode and at least one cathode, an inlet through which liquor may be charged to the electrolytic cell and an outlet through which liquor may be removed from the electrolytic cell, and means for recirculating liquor to the electrolytic cell, in which said recirculating means comprises a unit formed of a plurality of shaped sheets whch are preferably planar and together form at least one channel inside of said unit, said channel connecting the inlet and outlet of the electrolytic cell.

Abstract: Benzaldehyde dialkyl acetals of the formula ##STR1## where R is alkyl of 1 to 4 carbon atoms, are prepared by electrochemical oxidation of 3-tert-butyl-4-methoxytoluene in the presence of an alkanol of the formula ROH and are used as scents or scent intermediates.

Abstract: A transition metal electrocatalyst surface (e.g. a porous surface of finely divided Group VIII or Group I-B metal with an attached current collector) is modified by a sulfur treatment, using an oxidized sulfur species of average sulfur oxidation state of about 4 or less, e.g. SO.sub.2 dissolved in aqueous acid. Treatment of the transition metal with SO.sub.2 or the like typically provides up to 100% coverage of the surface electrocatalyst sites with chemisorbed sulfur-containing species and perhaps subsurface effects as well, but washing or other non-electrochemical techniques can remove 5-90% (e.g. 25-70%) of the chemisorbed SO.sub.2 or the like from the surface, leaving substantially only a very strongly bound form of the sulfur-containing species. The strongly bound sulfur-containing species can then be reduced to form a highly beneficial, selectively-improving pattern of sites containing reduced -S (e.g. sulfur or sulfide) on the electrocatalyst surface.

Abstract: This invention comprises the use, during the plating processing of thin-film magnetic recording media, of an oxidizing treatment immediately preceding the electroplating of the magnetic layer. This oxidizing treatment can be controlled to produce desired high levels of coercive force and low levels of media noise.

Abstract: An improved diaphragm for an electrolytic cell is prepared by mixing a slurry of an additive, such as poly(ethylene chlorotrifluoroethylene), and asbestos fibers with a dispersion of titanium dioxide in isopropyl alcohol, depositing the treated asbestos fibers onto a cathode, heating the diaphragm to an elevated temperature of from about 100.degree. C. to about 400.degree. C., and allowing the diaphragm to cool.The diaphragm prepared according to this process exhibits improved mechanical strength and integrity as well as a decrease in electrical energy consumption in comparison to diaphragms prepared using conventional techniques.

Abstract: Superconducting ceramic material is prepared by mixing desired oxide powders, calcining them, forming a slurry of the calcined powders with a carrier liquid, depositing a layer of the ceramic from the slurry by electrophoretic deposition and then drying the layer. The layer should then be sintered to increase densification. Typical powders are oxides of Y, Ba and Cu in molar proportions 1:2:3 respectively.

Abstract: Anodic formation of amorphous iron phosphate films in a dialkyl hydrogen phosphate electrolytic medium containing hydrogen-rich cation exchange resin particles having a free moisture content between about 9% and about 33% by weight.

Abstract: A hydrochloric acid-based chlorine dioxide generating process is integrated with an electrolytic process for sodium hydroxide production. Generator liquor in the form of a sodium chloride-enriched solution from the chlorine dioxide generator is passed to the central compartment of a three-compartment cell. Hydrogen ions formed in the anode compartment of the three-compartment cell migrate through a cation-exchange membrane to the central compartment to form hydrochloric acid with the sodium chloride solution while sodium ions migrate through a further cation-exchange membrane to form sodium hydroxide with hydroxyl ions produced in the cathode compartment of the three-compartment cell. The acidified generator liquor containing the hydrochloric acid formed in the central compartment is forwarded to the chlorine dioxide generator to provide half the acid requirement therefor.

Abstract: An electrolyte permeable asbestos diaphragm is prepared by depositing asbestos and a particulate thermoplastic polymeric material from an aqueous slurry including alkali metal hydroxide onto a porous substrate, and heating the deposited asbestos, particulate thermoplastic polymeric material, and alkali metal hydroxide for a period of time, e.g., at least 2 hours, and at temperatures sufficient to react the asbestos and alkali metal hydroxide but temperatures insufficient to melt or sinter the particulate thermoplastic polymeric material, whereby the particulate thermoplastic polymeric material functions to provide permeability for the diaphragm.

Abstract: A method for producing NF.sub.3 by fused salt electrolysis of electrolytes containing hydrofluoric acid salts of ammonia and of hydrazine and electrolyte mixtures for use therein.

Abstract: An electrodeposition process and a bath therefore are disclosed for performing the electrodeposition of hard smooth coatings of trivalent chromium. The electrodeposition process is accomplished energy efficiently. The bath includes chromium chloride as a source of chromium, citric acid to complex the chromium, and a wetting agent which is preferably Triton x-100. Preferably, bromide is also provided in the solution to maintain the hexavalent chromium production at the anode at a low level. Ammonium chloride is also preferably provided to improve the conductivity and also the current distribution in the bath. Boric acid is provided to advance the reaction kinetics. The pH of the bath is maintained at approximately 4.0 and the temperature is maintained at approximately 35.degree. C. Either a direct current or pulsed current is used for the deposition process. Hard smooth coatings of trivalent chromium are deposited through use of the process and the bath of the claimed invention.

Abstract: Hydrogen and oxygen are obtained by the photocatalytic decomposition of water by passing light in an inert atmosphere through an aqueous solution of dioxygen complex of ruthenium and EDTA in which is suspended a semiconductor of hexagonal crystal structure loaded with a noble metal and a transition metal oxide. Hydrogen and oxygen are known to have various uses. Precipitation of the semiconductor material and annealing it at a temperature from 300.degree.-350.degree. C. result in the semiconductor of hexagonal structure which is suspended in the aqueous solution.

Abstract: Included is a process for electrodepositing a high purity metallic containing alkaline earth metal on a conductive substrate comprising operating an electrochemical cell having(1) an anode selected from the group consisting of a passive anode and a sacrificial alkaline earth metal containing anode;(2) an electrolyte containing an aprotic solvent and a solute of a minor amount of residual halogen containing synergist and a major amount of residual alkaline earth metal, and(3) a cathode, which contains the conductive substrate,under conditions whereby said electrodepositing occurs. For example, a most pure crystalline magnesium deposit can be prepared with tetrahydrofuran, aluminum trichloride and ethylmagnesium chloride, employing either an inert carbon, or a sacrificial magnesium containing, anode.

Abstract: Solid compositions based on superoxides comprise a material inert with respect to O.sub.2 - anions playing the role of matrix with regard to these anions, and O.sub.2 - anions, these compositions forming a material stable up to about 100.degree. C. This matrix permits the mobility of the O.sub.2 - anions in this temperature region. These compositions are usable as electrolytes (1) in an electrochemical cell.

Abstract: A process for the production of Mg metal from impure Mg-containing materials is disclosed. The process comprises the steps of reacting a slurry of impure Mg-containing material with a hot HCl-containing gas stream to produce an impure MgCl.sub.2 slurry, purifying the MgCl.sub.2 slurry to form a substantially pure MgCl.sub.2 solution, drying the substantially pure MgCl.sub.2 solution to produce a MgCl.sub.2 powder containing up to about 5% each of MgO and H.sub.2 O, dehydration melting of the MgCl.sub.2 powder to produce molten anhydrous MgCl.sub.2, performing electrolysis of the molten anhydrous MgCl.sub.2 to produce Mg metal and Cl.sub.2, and recycling all of Cl.sub.2 produced during electrolysis to the above dehydration melting step for converting MgO and H.sub.2 O present in the MgCl.sub.2 powder into MgCl.sub.2 and HCl and for producing the hot HCl-containing gas stream. Dehydration melting is preferably done by feeding the MgCl.sub.2 powder into the feed end of a rotary kiln, and reacting Cl.sub.

Abstract: The existing processes for the preparation of halogenoacrylic acids and deuterated derivatives thereof have to be carried out using chemicals which are in some cases very toxic or very expensive.Electrochemical reduction, however, makes it possible to eliminate one or more halogen atoms selectively from halogenoacrylic and halogenomethacrylic acids and derivatives thereof, and to replace these by hydrogen or deuterium atoms.This is effected by electrolyzing the acids or derivatives thereof in a solution containing water or deuterium oxide at a temperature from -10.degree. C. up to the boiling point of the electrolysis liquid.