Distillation relies on differences in boiling points in two liquids. The vapour that is driven off will be richer in one component than the original mixture.
One way of separating dissolved material is by steam distillation, which applies a carefully controlled heat which does not harm delicate molecules.
Much of industry depends on effective ways of preparing pure chemicals in significant amounts at a sufficiently low price and at a low cost to the environment.
Much of 19th and 20th century chemistry aimed to find ways to prepare industrial quantities of key chemicals that were needed in textile and other industries.
The Solvay process was developed as a way to produce sodium carbonate, which was and is an essential industrial chemical in many manufacturing operations.
Gases that are insoluble may be collected by the downward displacement of water, soluble gases require more complex arrangements so as to collect pure samples.
Destructive distillation is used to prepare some materials, and usually involves chemical change. It is more heating in the absence of air than distillation
One way of separating dissolved material is by dialysis, which involves filtration through a membrane under some form of active transport or pressure.
As a form of separation, sedimentation relies on differences in density, with more dense solids in a fluid finding their way to the bottom of a container.
Filtration relies on differences in the size of particles or molecules, with sufficiently small particles getting through, while larger ones are trapped.
In 1906, Mikhail Semenovitch Tswett (or Tsvett) first used paper chromatography to separate plant pigments from each other, allowing them to be analysed.
Chromatography relies on differences in attraction, whether from the solvent or the substrate. This applies to paper and gas chromatography and electrophoresis.
In 1944, Fred Sanger used chromatography to determine the amino acid sequences in bovine insulin and completed it after ten years of exhaustive work.