A method for metering ammonia into the exhaust-gas region of an internal
combustion engine and a device for implementing the method. The ammonia
storage capacity of an SCR catalytic converter situated in the
exhaust-gas region of the internal combustion engine is utilized. After
the internal combustion engine has been switched off, ammonia is
introduced into the exhaust-gas region in front of the SCR catalytic
converter. Thus, following a renewed start-up of the internal combustion
engine, the ammonia required in the SCR catalytic converter for reducing
the nitrogen oxides contained in the exhaust gas of the internal
combustion engine are already available before an ammonia source is ready
for operation. The procedure eliminates the need for a pressure storage
of ammonia in the switched-off state of the internal combustion engine.