Isn’t it also possible to purify by distilling it, as if it were sea water, and the copper, etc would end up as salts?
“distilling it”
My son was a chemist and warned me years ago about drinking distilled water. He said it is blank of anything and will leach minerals out of your bones and body. You would not want that happening in an emergency situation that lasted a while.
Not sure about the salts and trace minerals.
I have seen people , especially those from the South , who say that they will get water from their air conditioner (assuming electrical power exists)in SHTF
That water is basicly condensation without benefit of trace minerals or salts.
Liquid yes , ... but absent of trace minerals and salts necessary for cellular developement or cellular replication .
It might be suitable for growing crops in drought conditions,but those same plants would get missing minerals and salts from contact with the ground.