PROTECTION METHOD OF CATHODE UNITS WITH WETTED COATING BASED ON TITANIUM DIBORIDE AT BAKING OF ELECTROLYSIS UNIT Russian patent published in 2013 - IPC C25C3/06 

FIELD: metallurgy.

SUBSTANCE: method involves application to a wetted coating of a protective layer preserving protective properties in the whole temperature range of electrolysis unit baking with fusion temperature that is higher than maximum baking temperature and diluted at interaction with alumina-cryolite melt of electrolyte Na₃AlF₆·Al₂O₃. As protective layer, a layer is used, which is based on water alkaline solution of sodium silicates Na₂O(SiO₂)n or potassium silicates K₂O(SiO₂) and thermally stable component, or a layer is used, which is based on water alkaline solution of sodium silicates Na₂O(SiO₂)n or potassium silicates K₂O(SiO₂). Protective layer is applied in the following proportions of 30 to 100% (Na₂O(SiO₂)n or potassium K₂O(SiO₂)) and 30% to 70% of thermally stable component. Pulverised carbon or alumina Al₂O₃ is added as thermally stable component to water alkaline solution.

EFFECT: improving protective properties of wetted coating due to increased stability of a protective layer in local bottom overheat sections at baking of an aluminium electrolysis unit.

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