Abstract: Hexafluoroacetone hydrate is obtained with a high current efficiency by electrolytically oxidizing dimer or monomer of hexafluoro-.alpha.-hydroxyisobutanoic acid in an electrolytic solution composed of an aqueous solution of (1) a nickel salt and (2) HCl, HBr or an alkali metal or alkaline earth metal thereof.

Abstract: The invention relates to a method for selectively recovering lead from complex sulphidic non-ferrous metal concentrates in an electrolytic cell incorporating at least one anode and one cathode and an electrolyte containing chlorine ions, at a temperature beneath the boiling point of the concentrate-containing electrolyte and at a pH beneath 7. Sulphur present in the concentrate is converted substantially into elementary form, and at least the major part of the lead content passes into solution and is then precipitated selectively by cathodic processes. The invention is characterized in that the concentrate is slurried in an electrolyte having a chloride-ion strength above about 2 M, preferably in the range 3-5 M, to form a suspension which is caused to flow into contact with or adjacent the surface of anodes located in the cell; and in that the highest possible anodic current density considering required selectivity is maintained during the electro-winning process.

Abstract: A process and an apparatus are described for regenerating an electroless copper plating bath containing a complexing agent, preferably ethylenediamine tetraacetic acid. From the bath solution to be regenerated, the copper content is reduced by electrolysis to a value below 20 mg/l and the complexing agent subsequently precipitated by acidification and recovered. After dissolution in an alkaline electrolytic solution, the solution thus obtained is fed back to the electroless copper plating bath. A particularly pure ethylenediamine tetraacetic acid free from by-products is obtained if the pH value is kept constant during electrolysis, an anodic current density i.sub.+ of 100 A/m.sup.2 is not exceeded, and the anodic current density during electrolysis is reduced according to the electrolysis characteristic or in steps.

Abstract: A method and apparatus for providing two chemical products includes a reaction cell having an anode chamber and a cathode chamber. The anode chamber is separated from the cathode chamber by an ionic transfer membrane. Each chamber has an electrode connected to a source of DC voltage. A first electrolyte with a first sparging gas is provided to the anode chamber, while a second electrolyte with a second sparging gas is provided to the cathode chamber. The DC voltage, in cooperation with the electrolytes and the sparging gases causes products to form, one in each chamber. The first product is removed from the reacted electrolyte that emerges from the anode chamber while the second product is removed from the reacted electrolyte emerging from the cathode chamber.

Abstract: An adherent, smooth electrodeposit of chromium is produced on a nodular cast iron substrate from a chromium plating bath. The desired deposit is provided herein by activating the substrate, subjecting the activated substrate to an ultrasonic treatment, and thereafter plating chromium from a chromium plating bath. The method is particularly effective for electrodeposition of chromium on such substrates from commercial high energy efficient chromium electroplating baths, where ordinarily only roughened deposits are obtained.

Abstract: An electrogenerative cell and a process for the oxidation or halogenation of hydrocarbons is disclosed wherein a cell body containing a permselective membrane which divides said cell body into anolyte and catholyte compartments containing a liquid electrolyte consisting repectively of anolyte and catholyte and a porous anode and a porous cathode. Anolyte and catholyte compartments are fed respectively with a mixture of a liquid electrolyte and an unsaturated hydrocarbon and a mixture of a liquid electrolyte and a halogen or oxygen, wherein said electrolytes are fed to said cell at ambient or elevated temperature and pressure. A halogenated or oxygenated hydrocarbon is recovered and electrolytes, unsaturated hydrocarbon, halogen or oxygen are recycled to the cell.

Abstract: What is described herein is an improved method of electroplating an adherent chromium deposit on a chromium substrate. The process is characterized by chemically oxidizing the chromium substrate before starting the electrodeposition of chromium thereon. A suitable chemical oxidizing agent is hydrogen ion, which can be furnished by a dilute acid solution. In this invention, the acid is characterized by being destroyed in the plating bath, if dragged therein. Suitable acids include oxalic and citric acids. The process is applicable to any chromium electroplating bath, including high energy efficient chromium baths, such as HEEF-40 baths, which are presently in commercial use.

Abstract: Carbon fibers subjected to an electrolytic treatment in an oxidizer bath followed by electrolytic treatment in an ammonium bath have surface elemental content of oxygen greater than 7% and nitrogen greater than 4%. Composites based on the carbon fiber in combination with bis-maleimide type matrix resins have improved toughness and interfacial bonding.

Abstract: Method for extracting metals amalgamatable with mercury from fluid material containing those metals in the form of metal particles. The method comprises contacting a slurry or aqueous solution containing metal particles of the metal to be recovered by amalgamation with a surface of a support amalgamated with mercury to form on the surface an amalgam with the metal to be recovered. A surface film is continuously removed from the surface of the support, and the surface of the support is continuously restored by electrolytic deposition of mercury thereon.

Abstract: An improved process for preparing a phosphated metal surface for painting comprises electrolyzing the surface as cathode in an aqueous solution containing hexavalent and trivalent chromium in specified concentrations and weight ratios.

Abstract: Laminates of metals and electrically conductive polymers are prepared by a process in which first a layer of an electrically conductive polymer is applied onto the surface of the metal by treating the monomers with an oxidizing agent, the metal coated in this manner is immersed in a solution which contains an anodically polymerizable monomer and a conductive salt, and the monomer is anodically polymerized so that it is deposited onto the coated metal.

Abstract: An electrolytic silver recovery apparatus for the recovery of metallic silver from silver-laden solutions is disclosed. The apparatus has liquid level controls, interval electrical power controls, and a removable cathode. The apparatus is used particularly in conjunction with x-ray film developing systems to recover silver values from spent fixer solution in a manner whereby at least a substantial portion of the fixer solution may be returned to the film processor's replenishing tank for reuse.

Abstract: The disadvantages of difficulty in operation of the bath and unfavorable physical properties obtained with the simultaneous deposition of metal and a permanent solid lubricant in electroplating baths of conventional composition and containing solid lubricant particles and a perfluorized compound acting as a cationic tenside are avoided if, instead of the perfluorized compound, the bath contains ##STR1## where A.sub.1 -A.sub.9 is H or an alkyl radical with low C number, R.sub.1 -R.sub.9 is H, OH or an alkyl radical with low C number, X is a halogen or SO.sub.4 and n is the valency of X. Preferred solid lubricants are polytetrafluoroethylene, graphite, graphite fluoride or molybdenumdisulfide.

Abstract: An electrolytic silver refining process in which crude silver is anodically dissolved and refined silver is cathodically deposited and at the same time accompanying metals are selectively extracted from the spent electrolyte and separately cathodically deposited after having been transferred into an aqueous phase and the regenerated electrolyte stripped of accompanying metals is recycled to the refining process and in which further the spent electrolyte is anodically enriched in silver and accompanying metals are cathodically deposited from the aqueous phase in a joint electrolysis step.

Abstract: A method of converting olefins, preferably butylene or propylene into oxides is disclosed. A metal halide salt, preferably KBr, is introduced into an electrochemical cell wherein the cathode has a gas side preferably supplied with oxygen and operated at a low voltage to suppress hydrogen production.

Abstract: Water is decomposed into hydrogen and oxygen gases by impressing alternate ones of a plurality of sheet electrodes a direct current of given polarity having low voltage and high amperage while simultaneously impressing on the cathode and anodes of a plurality of electrolytic cells, individually sandwiched between the sheet electrodes a high voltage and low amperage direct current, while the sheet electrodes and the electrolytic cells are all immersed in an aqueous electrolyte solution.

Abstract: A method for imparting wettability to an aluminum heat exchanger comprises immersing the heat exchanger in an aqueous medium containing a silanol compound and polyvinyl pyrrolidone. If desired, the exchanger may be conversion coated or anodized prior to the immersion.

Abstract: The invention comprises processing together an electropolymerized polymer and the anode on which it is formed by shaping them or by size reducing them and dispersing the resulting size reduced material into a liquid vehicle for production of a coatable composition.

Abstract: An improved process is disclosed for carbothermically producing an alkaline earth metal aluminide from an aluminum-bearing material which, in one aspect comprises forming a mixture of a carbonaceous reducing agent and a slag comprising the aluminum-bearing material, the alkaline earth metal compound, forming, at a first temperature, an alloy containing impurities in the slag; removing the alloy containing the impurities from the slag; and then heating the slag to a higher temperature to form the alkaline earth metal aluminide. The alkaline earth metal compound used in the process may comprise calcium carbide. Alternatively, both the alkaline earth metal compound and the aluminum-bearing material may be obtained using a calcium aluminate slag such as a byproduct from the steel industry. The calcium aluminate slag is purified in a preliminary step to remove silicon by alloying it with iron and then removing a ferrosilicon alloy formed in this step.

Abstract: A method for electrolytically pretreating a cation exchange membrane by partitioning a first aqueous electrolyte solution from a second aqueous electrolyte solution with the membrane and then passing an electrical current through the system so that the cations of the first solution electro-migrate through the membrane into the second solution. The cation composition of the first solution being more than 99.99% of hydrogen ion and a single cation moiety selected from the group consisting of alkali metal cations and alkaline earth cations, the cation composition of the second solution consisting essentially of the same cation composition as the first solution. The result is a membrane that is almost completely equilibrated with the cations of the first solution. The pretreated membrane is especially suitable for use in the sensor for chemical analysis described in U.S. Pat. No. 4,333,810.