Either evaporation or crystallization.
boil the water away, leaving the salt in the bottom of the pot or whatever you used.
For example using ion exchangers.
salt when dissolved in water will become an acidic solution
No, a salt is a compound. A salt maybe dissolved in water and made into a solution but as salt is not a solution per se.
When salt is dissolved in water, it is in a dissolved state where the salt particles break apart into ions. This creates a solution where the salt ions are surrounded by water molecules.
Brine.In your example, the salt is the solute while the water is the solvent.
Salt water can be treated to remove the dissolved chemicals - making it safe to drink or bathe with.
When salt is dissolved a water sodium chloride solution is obtained.
The separated salt is a crystalline solid; the dissolved salt is dissociated in ions.
Salt
The Life Straw will not desalinate salt water, remove dissolved chemicals or minerals, nor remove viruses.
Salt is very soluble in water.