GB1312319A - Electrolytic cell - Google Patents

Abstract

1312319 Electrolytic cells for adiponitrile production ASAHI KASEI KOGYO KK 7 May 1970 [7 May 1969] 22141/70 Heading C2C [Also in Division C7] An electrolytic cell for producing adiponitrile by hydrodimerization of acrylonitrile comprises anode and cathode plates 9, e.g. fitted as dual electrodes in electrode frames 1 flush in opposite sides of an insulating board 8 therein and electrically connected together by a conductive rod 10, with membranes 3 between adjacent anode and cathode plates, and a duct 22, 23 formed between each membrane and cathode plate, and preferably anode plate also, having at least one turning portion therein positioned outside the current path to form a longer path for electrolyte flow than the length of one side of the plate 9. As shown, each electrode plate 9 fitted in the frames 1 forms a cathode confronting the anode frame 4 and an anode confronting the cathode frame 5, the whole being inside a pair of press heads 6. The membranes 3 are preferably cation-exchange membranes and 0À5-2 mm. thick, e.g. sulphonic type based on styrenedivinyl benzene or butadiene, reinforced with glass fibre. Electrode plates may be of Pb, Pb alloy, e.g. Pb-Sb and/or Ag, C, the cathodes additionally of Cd or Zn, the anodes of PbO 2 , FeO or Pt. The ducts may be formed by cut-outs in spacers 2 positioned between the membranes and plates; the turning portions thereof may be formed by grooves carved in the frames 1 or provided within the spacers. An aqueous solution containing acrylonitrile and tetraalkyl ammonium salt is fed, e.g. via conduits 11 to cathode chambers 22 while H 2 SO 4 solution is fed to anode chambers 23, formed by the ducts. The spacers, frames and conduits may be of polypropylene, rubber or vinyl chloride. The flow rate of catholyte on the cathode surface is preferably above 10 cm./sec. to reduce the alkaline layer formed at the cathode.