GB1258619A - - Google Patents

Abstract

1,258,619. Electrolytic production of adiponitrile. BADISCHE ANILIN & SODA-FABRIK A.G. March 14, 1969 [March 16, 1968; Oct.24, 1968], No.13524/69. Heading C7B. Adiponitrile is produced by electro-chemical hydrodimerization of acrylonitrile in a reaction mixture comprising acrylonitrile, a quaternary ammonium salt, water and if desired an organic solvent for acrylonitrile, at 10-60‹C. and pH = 1-10; the reaction mixture being passed through a narrow gap between solid electrodes 0À05-2mm. apart, or through the gap obtained between a solid electrode immersed in, but not wetted by, a liquid electrode. The quaternary ammonium salt may a tetramethyl- or tetraethylammonium salt of a mono-alkyl sulphate, sulphate, fluoride, tetrafluoroborate, fluorosulphonate, toluene sulphonate or benzene sulphonate. The organic solvent used may be a lower aliphatic alcohol such as isopropanol, methanol or ethanol; acetonitrile; ethers which are mixible with water, such as tetrahydrofurane, dioxane and glycol monomethyl ether; an amide which may include an alkyl or dialkyl radical, e.g. formamide, diethylacetamide; N- methyl-pyrrolidone; or the end product adiponitrile. A lower aldehyde may also be present and carbon dioxide or boron trifluoride may be added during electrolysis. Various electrodes which may be used include lead; copper; silver; amalgamated lead, copper or silver magnetite; graphite; gold; platinized titanium; platinum foil adhered to graphite; graphite, nickel or titanium coated with lead dioxide; tungsten-nickel alloys or magnetite. As liquid cathode, mercury or galluim above 30‹C. may be used. Solid electrodes used with a liquid cathode may be of various shapes. Fig.3 illustrates apparatus for carrying out the invention using liquid cathodes. The bottom of the cell body 1 contains circular depressions 4 partly filled with the liquid cathode material. Cylindrical anodes 2, having the edges of their lower faces rounded, are immersed in the liquid cathodes. The reaction mixture is pumped by pump 11 through heatexchanger 12 and enters the cell through nozzle 9 centrally of the anodes so that a thin moving film of electrolyte is maintained between the anodes and their corresponding cathodes. Electrolyte then overflows at 10 and is recirculated.