"So this just becomes the means for us to get those chemicals already being used."
I think there are more than enough already. This usage would massively increase the output. As already mentioned using sodium chloride solution as the electrolyte in electrolysis is terrible way of producing hydrogen. There are far more efficient electrolysis methods that don't produce any nasty by-products. For example using sulphuric acid - the acid isn't consumed in the process and is left in the cell with just more water being added as hydrogen and oxygen are produced