A condenser utilizes membranes to separate Nitrogen from the air. A condenser also allows you to harvest salt water if it is placed next to a block of water.
Membrane gas separation is primarily used to separate atmospheric air into its two main components, nitrogen (78.08%) and oxygen (20.95%).
However trace elements like argon (0.93%), carbon dioxide (0.038%) and other inert gases can also be obtained this way. The membranes act as a permeable layer that gases move through at different rates, effectively separating the main components.