What is a method to separate salt from salt water?
A solution of salt water is prepared by mixing salt (solute) and water (solvent). Salt can be separated from salt water by using the differences in the properties of water and salt, that is, the solvent and the solute. Water evaporates to the gaseous phase at 100 degrees Celsius, while the salt does not. We can use boiling as the method of separation.
When we boil a solution of salt water, the water will evaporate at around 100 degrees C, leaving behind all the salt in the container. If we also want to recover water, the water vapors can be collected and condensed back to collect all the water.
If time is not a constraint, then we can just leave the salt water out in the open and water will evaporate on its own, leaving behind the salt. That is how salt was obtained from sea water, in older times.
Whenever separation needs to be done for a solution or a mixture, the differences in the properties of individual constituents can be used to our advantage.
Hope this helps.