I'm not even close to being a Dessicant Expert, but I don't think they remove air. I think they remove moisture from the air. I'm hoping that you get some solid answers to your questions, as I have some dessicant packs that I am about to put in with my ammo.
A gunfight is not the time to learn new skills.
If you ever have a real need for more than a couple of magazines, your problem is not a shortage of magazines. It's a shortage of people on your side of the argument. -- Art Eatman