[harry998]

Good evening all,

I have a solution brine with a 160g/L of chloride content. The majority of the chloride content is coming from sodium chloride but a small amount is coming from other chloride compounds. I need to determine the proportion of chlorides coming from sodium chloride and the remaining percentage however all the titration methods i find seem to cover all chlorides in general but nothing specific to sodium chloride.

The solution is an in house proprietary blend and the company are reluctant to release samples for outside testing does anyone know of sodium chloride specific methods?

Thanks in advance for all your help,
Harry

[Borek]

There is no way to differentiate between chloride ions coming for different sources, they are all identical.

What you can do is to determine chlorides total (by any method), and then sodium total. The difference will be "other chlorides".

[Corribus]

Assuming all sodium came from sodium chloride, of course.

[Borek]

Good point.

[harry998]

Thanks guys i saw my error nearly as soon as i posted ( forgot about the dissociation of salt in water ). perhaps you can help me with my thinking ( im an electronics / test engineer by trade ) ?

I add sodium chloride to water, the water acts as a polar solvent and separate's the sodium and chloride ions and they are free to move separately from each other under external forces such as electric fields.

But   if i distill the solution to remove the water i am left with sodium chloride again.

What happens if i add another ion to the solution and then distill? How do i work out what will remain? For instance if i added fe ions would i get a mix of sodium chloride and iron chloride or just residual iron?

Sorry for all the questions im trying to wrap my head around this slowly

[Corribus]

You can't just add iron (ferric or ferrous) ions, because there's always a counter-ion involved. If you add another salt, what you'd get when the water evaporates is a complex mixture of salts remaining in the residue. The precise composition will probably depend on all the ions involved because some combinations of ions are more favorable than others. But they'd all be there in some form or other.