| 摘要 |
1443502 Electrodes SIGRI ELEKTROGRAPHIT GmbH 31 Jan 1975 [2 Feb 1974 16 March 1974 25 April 1974] 4418/75 Heading C7B [Also in Division C1] An electrode, for use in a chlor-alkali mercury or diaphragm cell, production of chlorate or hypochlorite, oxidation of organic substances, extraction of salt from sea water or cathodic protection, comprises a base structure formed of TiO x where x is 0.25 to 1.50, at least partially covered by a surface coating containing at least one activating substance, e.g. Pd, Pt, Ir, Ru, Os, Rh, Au, Ag and/or oxides, nitrides, sulphides thereof. The electrode 1 may comprise rectangular top and bottom surfaces, either parallel Fig. 2 (not shown), or with the top surface 5 inclined to the bottom; formed in the bottom and extending between sides 3, 4 may be grooves 2 whose depth uniformly increases. Ribbed reinforcing elements may be provided on the grooves. The electrode is produced by compressing a TiO x powder (or mixture of Ti and rutile powder with polyvinyl alcohol binder), sintering at 900 to 1500‹C in an inert e.g. argon atmosphere and applying the activating substance(s). At least part of the surface of the base structure not covered by the surface coating may be provided with a sintered Ti coating for connection to Ti current-supply rods or bars e.g. by soldering or welding. The Ti coating may be formed by (a) covering the TiO x powder with a layer of Ti powder and compressing the superimposed powder layers and sintering, (b) applying Ti powder with etherified cellulose binder to the shaped sintered TiO x body and sintering, or (c) applying the Ti to the shaped sintered body by flame or plasma spraying. For an activating surface coating, the shaped body may be coated with an acid alcoholic solution of RuCl 3 (H 2 O) 1.5 and H 2 PtCl 6 and heated in argon to burn in the layer. |
