THE INVENTION RELATES TO A DEVICE FOR DIFFUSING SUBSTANCE BY CATALYTIC COMBUSTION ALLOWING THE EMISSION OF VOLATILE MATTER COMPRISING: A CONTAINER (4) CONTAINING THE LIQUID TO BE VAPORIZED SAID CONTAINER (4) HAVING A WICK (6) COMPRISING A FIRST END WHICH IS DIPPED IN SAID LIQUID TO BE VAPORIZED AND A SECOND END WHICH IS OUTSIDE OF SAID CONTAINER (4) AND A DIFFUSION HEAD (2) COMPRISING A CATALYTIC COMBUSTION AREA AND A VAPORIZATION AREA CHARACTERIZED IN THAT SAID DIFFUSION HEAD (2) IS CONNECTED DETACHABLY TO SAID SECOND END OF SAID WICK (6). FIGURE 1.