GB1156955A - Electrolytic Hydrodimerisation - Google Patents

Abstract

1,156,955. Electrolytic hydrodimerisation of compounds. RHONE-POULENC S.A. June 30, 1967 [June 30, 1966], No. 30370/67. Heading C7B. A process for the hydrodimerisation of ethylenically unsaturated monomers of the general formula: where R 1 , R 2 and R 3 represent a hydrogen atom or hydrocarbon radical and Z represents a ketone, ester, nitrile, amide or aldehyde group, e.g. of acrylonitrile to form adiponitrile, comprises electrolyzing a mixture of (a) the monomer; (b) water, the ratio of monomer/water being from 15/85 to 75/25 by weight; and (c) 10 to 30% by weight of (a), (b) and (c) of (c) a buffer containing at least one quaternary ammonium salt of an oxygen-containing inorganic acid having a pK in water of 5-11, the components of the buffer being in such ratio that the pH of their aqueous solution is 6-10. The buffers used may comprise alkyl quaternary ammonium salts of weak acids such as borates, carbanates, bicarbonates and orthophosphates, e.g. a tetra-(n-butyl) amminium salt. The process may be carried out in a diaphragm or single compartment cell. The cathode used may comprise mercury, graphite, lead, lead/ mercury alloy or Darcet alloy (Bi-Sn-Pb). The anode may be formed of lead or nickel, the surface of which may be oxidized, platinum deposited on to graphite, gold or stainless steel. The interelectrode gap may be 1-15mm.