While the three methods described under normal water purification methods will remove only microbes from water, the following two purification methods will remove other contaminants. Distillation will remove microbes, heavy metals, salts, most other chemicals, and radioactive dust and dirt, called radioactive fallout. Filtering will also remove radioactive fallout.
Distillation involves boiling water and then collecting the vapor that condenses back to water.
The condensed vapor will not include salt and other impurities. To distill, add a rack or something to keep a coffee cup out of the water. Fill a pot part way with water. Place an upside down pot lid on the pot and boil the water for 20 minutes. The water that drips from the lid into the cup is distilled.