This invention relates to a method of operating a catalyst for treating
the exhaust gas of an internal combustion engine, the catalyst
comprising, in addition to catalytically active noble metals, also
storage components for storing hydrocarbons. During engine operating
phases at low exhaust-gas temperatures, such a catalyst stores the
hydrocarbons contained in the exhaust gas without burning them. When the
exhaust-gas temperature rises, these hydrocarbons are desorbed again and
then oxidized at the catalytically active noble metals. This process can
lead to uncontrolled, vigorous combustion of the hydrocarbons stored on
the catalyst and, therefore, damage to the catalyst. According to the
invention, this damage is avoided by continuously calculating the
respective loading of the storage components with hydrocarbons and
repeatedly regenerating the storage components depending on the loading
by temporarily raising the exhaust-gas temperature before damage to the
catalyst can occur.