I bet it IS the crystal. Think about it. We don't know much about it, only that getting too close means being disintegrated. That must mean that even smoke must get disintegrated by it.
Ok, its the quote which i chosen as the most sesnsless of the whole thread ;P
So you are basicaly saying that when the molecule approaches crystal, it disappears? But you want only the CO2 and other waste to do so... What about Nitrogen?

And more imortant, what about molecules of O2 ?

I bet they disappear too !!
But what do we breath after that?
Furher, why won't the rock around crystal won't disappear too?

What would stop it from making the whole planet to disappear?

But after all this we would have evil space crystal travelling through the space and looking for other worlds to disappear \o/
On other topic. CO2 is heavier than O2 so its the bottom leavels who would be pretty sc****.
And i believe its the photosynthesis and rain which make the air breathable.
photosynthesis for CO2 and rain for dissolved in air residues.