A metal or metal compound able to trap a sulfur component in exhaust gas is arranged in a flow passage of exhaust gas in an internal combustion engine. When the amount of sulfur component trapped in the metal or metal compound increases over the passage of time, a property of the metal or metal compound...http://www.google.com/patents/US8161794?utm_source=gb-gplus-sharePatent US8161794 - Sulfur component detecting device
