THREE-WAY CATALYST (TWC) SYSTEM 7M-GE (Federal and Canada) NOx, CO, HC Three-Way Catalyst (Monolithic) CO₂, N₂, H₂O 7M-GE (California) NOx, CO, HC Three-Way Catalyst (Monolithic) Three-Way Catalyst (Monolithic) CO₂, N₂, H₂O 7M-GTE NOx, CO, HC Three-Way Catalyst (Monolithic) Three-Way Catalyst (Monolithic) CO₂, N₂, H₂O EC-1422 Figure EC-20-1 To reduce HC, CO and NOx emission, they are oxidized, reduced and converted to nitrogen (N₂), carbon dioxide (CO₂) and water (H₂O) by the catalyst. Exhaust Port HC, CO, AND NOx TWC OXIDATION AND REDUCTION Exhaust Gas CO₂ H₂O N₂