HC trap system comprising an oxygen storage component material

摘要

A hydrocarbon (HC) trap system for a spark ignition internal combustion engine comprising a temperature sensitive absorber material and a sacrificial oxygen storage component (OSC) material which loses oxygen storage capacity between ambient temperature and an elevated temperature, at which the temperature sensitive absorber material has degraded and does not trap HC. Preferably the OSC degrades at an elevated temperature below 800°C and may comprise ceria-zirconia, manganese -titania or manganese-aluminate. The HC trap system may also be combined with a sensor for determining the oxygen storage capacity of the HC trap system and an electronic control module which can receive a signal from the sensor and determine whether the sacrificial OSC has been exposed to a temperature at which the HC trap material has degraded. A method of on board diagnostics (OBD) for a HC trap is also claimed.