Oxygen in a bottle??

Oxygen and other gas and liquid bottles are created when you deconstruct a building that had them inside of it. You can sweep liquid bottles into bottle emptier with that liquid set into it, but you cant do that with gas bottles. With gas bottles you need to click on the bottle( sometimes hard as the bottle doesnt match the clicking area fully) and select emtpy. This empties the gases to that tile and gets rid of the bottle

Yeah, after about an hour of game play it let me "empty" it, where I'm not sure.