Purification is the process of rendering something pure, i.e. clean of foreign elements and/or pollution. This can refer to:

Physically separating a substance of interest from foreign or contaminating elements, and can take one or more of the following forms

• Filtration is a mechanical method to remove solids from liquids.
• Condensation or distillation is used to remove soluble substances from liquids, which cannot be done through filtration due to the small size of the substances.
• Smelting is used to produce metals from raw ore, and involves adding chemicals to the ore and heating it up to the melting point of the metal.
• Refining is used primarily in the petroleum industry, whereby crude oil is heated and separated into stages according to the condensation points of the various elements.
• Water purification combines a number of methods to produce potable or drinking water

In religious context, it can mean

• a ceremonial or ritual cleansing, such as baptism;
• the Christian liturgical feast named Purification of the Virgin.

In Economics, a Nash equilibrium consisting of randomly mixed strategies in a game can be interpreted as pure strategy equilibrium of a different game. See purification theorems.

Purificación