Asteroid Mining - Gas Storage Question

RE: " ... creating a lot of oxygen as a by-product of steel making...."
Iron meteors have hit the Moon over the eons and scattered their bits over
the surface, as they have on Earth. Since the Moon has no atmosphere or
photosynthesis (which make the Earth's atmosphere aerobic, and oxidized the
surface iron) there is lots of reduced iron in the regolith. All one has to
do to pick up "Meteorite Stainless" is to drag a magnet across the Moon's
surface. If you want oxygen as a by-product, go after some element which
has been oxidized, like silicon or aluminum.
Sincerely, Jay Huebner