where each of the components is a liquid can be separated by distillation

where each of the components is a liquid can be separated by distillation. For example, if you have a solution containing isopropanol and water, heating it will cause the isopropanol to boil off first, leaving the water behind.

You can do the same thing if you have a solid dissolved in a liquid, except that the liquid will boil away leaving only a solid behind.

Here is a video of an experiment which uses distillation to purify water from a solution of salt water. Video from: Noel Pauller