I think there are two ways to deal with getting moisture out of the air:
1. desiccants
2. cooling it down past saturation
The answer is #2. Air conditioning units and dehumidifier units, which are essentially the exact same thing except for where the hot air output goes. (AC's send the hot air outdoors; dehumidifiers mix it back with the now-dehumidified cold air.)
I'm not sure this is true. There's some nasty desiccants that can work effectively, but the trouble is usually in regeneration.