Method for manufacturing graphite electrodes for electrolytic processes

摘要

The method for the production of graphite electrode with a coating predominantly out of noble metal useful as electrode in the production of chlorine and hydrogen through hydrochloric acid electrolysis, comprises coating the surface of the graphite electrode with a liquid solution of noble metallic component, removing the solution and subsequently tempering the graphite electrode in the presence of reducing and/or extensively oxygen free gases at 250-350[deg] C for 2-3 hours. The produced noble metal coating consists of 7.5-20 g/m 2>of noble metal related to the graphite electrode base surface. The method for the production of graphite electrode with a coating predominantly out of noble metal useful as electrode in the production of chlorine and hydrogen through hydrochloric acid electrolysis, comprises coating the surface of the graphite electrode with a liquid solution of noble metallic component, removing the solution and subsequently tempering the graphite electrode in the presence of reducing and/or extensively oxygen free gases at 250-350[deg] C for 2-3 hours. The produced noble metal coating consists of 7.5-20 g/m 2>of noble metal related to the graphite electrode base surface. The portion of the oxygen in tempering gas is greater than 1 vol.%. The gas consists of a gas mixture out of nitrogen or noble gas with hydrogen. The hydrogen portion in the gas mixture is 1-5.5 vol.%. An independent claim is included for a graphite electrode coated with noble metal.