This is such an interesting technique to learn that I had to include it. The survival use is not clearly defined but there are so many directions you can go once you understand the basics of this creation. Are you keeping carbon on hand? I recommend keeping activated charcoal around for both survival and medicinal uses. You will find that this stuff can be very helpful. Charcoal is even a main ingredient in gunpowder!
This carbon air filter is a very interesting project on its own let alone with modified. I like to consider shrinking something like this to filter a gas mask or what about filtering air into a bunker? There are a lot of possibilities once you get the base materials and process created. What would you do with this air filtering technology.