Distillation, also known as classical distillation, is the process of selective boiling and condensation, usually inside a still, to separate the components or substances of a liquid mixture. The process of heating solid materials to produce gaseous products, which can condense into liquids or solids, is known as dry distillation. This could involve chemical changes like cracking or destructive distillation. Distillation can either result in a partial separation that raises the concentration of specific components or a separation that is nearly complete, producing components that are nearly pure. The procedure takes advantage of differences in the components of the mixture's relative volatility in either scenario. Distillation is a unit operation that is used in almost all industrial applications. However, it is not a chemical reaction; rather, it is a physical separation process. A distillery is a facility used for distillation, particularly of distilled beverages. Distillation of fermented products results in high-alcohol distilled beverages or separates other commercially valuable fermentation products. Desalination by distillation is a tried-and-true and efficient process.

Oil stabilization is a type of partial distillation used in the petroleum industry to lower the vapor pressure of crude oil, making it safe to store and transport and lowering the amount of volatile hydrocarbons released into the atmosphere. Fractional distillation is a major type of operation used in oil refineries' midstream operations to turn crude oil into fuels and chemical feed stocks. For industrial use, cryogenic distillation results in the separation of air into its components, particularly oxygen, nitrogen and argon. Large quantities of crude liquid products of chemical synthesis are distilled in the chemical industry to separate them from other products, impurities, or unreacted starting materials. On perfumery-related Akkadian tablets dated around 1200 BCE, early evidence of distillation was discovered. The tablets provided textual evidence that the Babylonians of ancient Mesopotamia were familiar with a primitive early method of distillation. Alchemists working in Alexandria in Roman Egypt in the first century also provided early evidence of distillation. Baked clay retorts and receivers from Taxila, Shaikhan and Charsadda in Pakistan, as well as Rang Mahal in India, which date back to the early Common Era, show that distillation was used in the ancient Indian subcontinent. These terracotta distillation tubes, according to Allchin, were made to look like bamboo. There was no effective way to collect the vapors at low heat, so these Gandhara stills could only make very weak liquor. Distilled water has been used since Alexander of Aphrodisias described the process around 200 CE. Under Zosimus of Panopolis in the third century, work on the distillation of other liquids continued in the early Byzantine Egypt. According to archaeological evidence, beverages were first distilled during the Jin and Southern Song dynasties. Distillation in China may have begun during the Eastern Han dynasty. By the end of the thirteenth century, recipes for distilling wine with salt to produce aqua ardens (literally, burning water or ethanol) were appearing in a number of Latin works. By then, Western European chemists had come to know it well. Repeated distillation through a water-cooled still in the works of Taddeo Alderotti (1223-1296) is described as a method for concentrating alcohol that yields an alcohol purity of 90%.

With Regards,
Joseph Kent
Journal Manager
Journal of Der Chemica Sinica