| 摘要 |
1373611 Lead dioxide electrode ELECTRICITY COUNCIL 5 Jan 1972 [12 Jan 1971] 1502/71 Heading C7B A process for producing an electrode consisting of a titanium substrate coated with lead dioxide in valves degreasing the titanium substrate, removing the titanium oxide film by cathodic polarization and then anodically depositing lead dioxide from a solution containing one or more lead salts such that the anode current density is increased during the electro-deposition. The titanium substrate may be an expanded grid or gauze and may be sealed in a rim of plastics material. The degreasing solvent may be trichloro ethylene. The electrolyte for the cathodic treatment may be sulphuric or hydrochloric acid and the counterelectrodes may be platinized titanium or lead dioxide. The electro-deposition of lead dioxide may be carried out in two parts. In the first part the anode current is 20-50 mA/cm<SP>2</SP> for ¢-2 hrs and in the second part 50-100 mA/cm<SP>2</SP> for ¢-3 hrs. The cathodic may be stainless steel, nickel, platinum or copper and may be in the form of wire wound around a hollow former. The electrolyte for the anodic deposition may contain lead nitrate, copper nitrate, nickel nitrate, sodium fluoride, nitric acid and heptafluorobutanol. Reference is made to Specification 1192344 and 1189183. |
