Then there is the chemical method (oxygen), which basically does not produce hydrogen.
Only electrolysis (water) method can obtain oxygen and hydrogen, and the general output is very small. (Laboratory equipment, mainly used for preparing hydrogen)
Hydrogen will be obtained when salt is electrolyzed in chlor-alkali industry, but there is a special recovery device and it will not be vented.
I asked the Institute of Special Gases for you. They should be experts. There is an objection to this.
(They tested Oxylide with many impurities. Now there is "Oxylide" to electrolyze water to produce oxygen. Look at the principle, it's very confusing. There is also a so-called "patent", which does not talk about electrolytic water at all, but uses high temperature to "decompose" ozone. )
Electrolysis produces oxygen and hydrogen. All for industrial purposes.
I also looked it up online. I guess it's a lie.
If water and H2O are electrolyzed, there must be hydrogen, which is very dangerous.
What uses ozone (O3) to reduce oxygen and what absorbs dissolved oxygen (TOD) in water may be deceptive.