| 摘要 |
1348785 Bipolar electrodes; electrolysis of alkali metal hydroxide IMPERIAL CHEMICAL INDUSTRIES Ltd 4 May 1971 [26 May 1970] 25201/70 Headings C6 and C7 A bipolar electrode unit for an electrolytic cell comprises (a) an anode 1 consisting of a sheet of Ti, Zr, Ta, Nb, W or alloy thereof having on one surface a coating of an electrode material (see below) and having its other surface electrically conductively bonded to a first sheet 2 of iron or steel, and (b) a cathode consisting of a foraminous sheet of iron or steel 9 parallel to, spaced apart from and in electrical connection with the first sheet of iron or steel. The electrode coating material may comprise a platinum metal or oxide (e.g. rhuthenium oxide), boride, phosphide or silicide thereof, or rhenium, rhenium trioxide, magnetite, titanium nitride and may also contain non-conducting oxides such as titanium or tin oxides. The anode sheet and the first iron or steel sheet may be brazed or soldered together, or bonded using a conductive cement, e.g. an epoxy resin having a zinc or silver filler. The cell shown for electrolysis of alkali metal chloride to form chlorine and alkali metal hydroxide, comprises two bipolar electrodes as described, a monopolar cathode 25 and a monopolar anode 20, diaphragms 15 (e.g. of PTFE with a titanium dioxide filler, or of asbestos) being provided adjacent the foraminous cathode grids, and defining anode and cathode departments; the anode compartment being provided with a brine inlet 5 and brine/chlorine foam outlet 6; and the cathode compartment being provided with gas and liquid outlets 23, 24 respectively. The brine chlorine foam is passed to a chamber for the separation of the chlorine and regeneration of the brine prior to recirculation. |
