Abstract: 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).