The best-known use for cerium is in ‘flints’ for cigarette lighters: Cerium Pocket Lighter (1922).
Cerium was incorporated into the screens of cathode ray television tubes to prevent the glass from darkening and becoming discoloured: Cerium-Containing Screen For Cathode Ray Tube (1957).
Cerium(Ill) oxide is used in catalytic converters: Cerium Oxide With Pores Having A Lamellar Structure, Preparation Method Therefor And Use Thereof In Catalysis (1999).
Cerium(III) oxide nanoparticles are being studied as an additive for diesel fuel to help it burn more completely and reduce exhaust emissions: Conductivity Improving Combination Of Cerium Oxide And Detergents For Diesel Fuels (2008).
Ceric oxide is an abrasive and polishing compound: Polishing Compositions Based On Cerium And Process For The Preparation Thereof (1991).
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All patent information has been obtained from Espacenet (European Patent Office).