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.
Distillation, widely used in petroleum refining and in purification of ethanol separates volatile liquids on the basis of their relative volatilities.
Water purification combines a number of methods to produce potable or drinking water.
Downstream processing refers to purification of chemicals, pharmaceuticals and food ingredients produced by fermentation or synthesized by plant and animal tissues, for example antibiotics, citric acid, vitamin E, and insulin.
Fractionation refers to a purification strategy in which some relatively inefficient purification method is repeatedly applied to isolate the desired substance in progressively greater purity.
Electrolysis refers to the breakdown of substances using an electric current. This removes impurities in a substance that an electric current is run through
Sublimation is the process of changing of any substance (usually on heating) from a solid to a gas (or from gas to a solid) without passing through liquid phase
These are all the methods of purification in Chemistry. ^^^^^^