can i make a carob filter for my inline fan??

i am buying a 4'' vortex inline fan..would i be able to make some sort of filter for the smell my friend is selling me this fan for really cheap any one have ideas??

look in the diy subforum there is a diy carbon filter there

Not my idea, I have never tried this but, saw it in another post here and it looked pretty cool. http://forum.grasscity.com/general-indoor-growing/273604-small-carbon-filter-diy.html