Ildfast belegg for komponenter i en aluminium elektrolyseovn

A refractory coating is provided for a component of an electrolytic cell for the production of aluminum in which an aqueous slurry is prepared comprising particulate refractory material, e.g. TiB2, dispersed in an aluminum oxalate complex. The slurry is applied as a coating to the surface of the component, e.g. a cathode block, and dried to form a hard refractory surface on the component. The aluminum oxalate complex may be formed in situ during production of the slurry by mixing together oxalic acid and electrostatic precipitator dust comprising aluminum oxide. After the refractory coated component is immersed in a high temperature cryolite bath of an aluminum electrolysis cell, the aluminum oxalate complex is converted to alumina which bonds the refractory particles to the surface of the cell component.