A device for connecting two conduit parts, in particular two parts of a pollutant fluid circuit, comprises a first connector part enclosing a first valve member elastically urged towards a first valve seat to isolate a fluid outlet. A second connector part comprises a tubular element defining an inlet conduit and enclosing a second valve member elastically urged towards a second valve seat to isolate a fluid inlet. A system is provided for cleaning contacting surfaces of the two connector parts and in particular those of the two valve members. The valve members have respective complementary shape mutually contacting surfaces and are adapted to be movable conjointly while remaining in contact so as to enable the fluid to pass.