To recover reformation performance of a reforming catalyst poisoned by sulfur composition in fuel in an internal combustion engine forming reformed gas containing hydrogen by supplying fuel in exhaust gas.

This internal combustion engine 1 is provided with a reformer 20 forming reformed gas Exr containing hydrogen by reforming mixture Gmr of exhaust gas and fuel for reformation by the reforming catalyst and the reformed gas is re-circulated to a combustion chamber of the internal combustion engine 1 via an intake air passage 3. Vapor of fuel evaporating in a fuel tank 70 is stored in a low sulfur fuel tank 60. The vapor is low sulfur fuel Fls containing fewer sulfur composition than fuel in fuel tank 70. A fuel injection valve 24 for reformation supplies the low sulfur fuel Fls to the reforming catalyst of the reformer 20.

COPYRIGHT: (C)2006,JPO&NCIPI