How long can it take in theory? We need to continue with the finishing work, and it's just impossible to be inside.
How and what to remove the smell of chlorine in the room after treating the walls against mold?
Only by airing, by draught. Raw walls will give an unpleasant smell for a long time, and if you dry them properly, then maybe the unpleasant smell of chlorine will be less or disappear at all.
Another option is to rinse the walls with water and lemon dishwashing detergent after treating them with chlorine. That's worse than airing it out, though.
Or maybe you should buy sodium hyposulfite. People call it so – antichlorine! You buy a package or several, dissolve the crystals in a little warm water in a ratio of one to three, and wipe all the walls or surfaces where there was whiteness.
Warning. Do not apply primer to the walls immediately after treating with chlorine products, this is a big mistake!!!
The best option is to initially purchase a chlorine-free mold remover and not bother with it later on.