In a

chemistry Chemistry is the science, scientific study of the properties and behavior of matter. It is a natural science that covers the Chemical element, elements that make up matter to the chemical compound, compounds made of atoms, molecules and ions ...

laboratory, a retort is a device used for

distillation Distillation, or classical distillation, is the process of separation process, separating the components or substances from a liquid mixture by using selective boiling and condensation, usually inside an apparatus known as a still. Dry distilla ...

or dry distillation of substances. It consists of a spherical vessel with a long downward-pointing neck. The

liquid A liquid is a nearly incompressible fluid that conforms to the shape of its container but retains a (nearly) constant volume independent of pressure. As such, it is one of the four fundamental states of matter (the others being solid, gas, a ...

to be distilled is placed in the vessel and heated. The neck acts as a condenser, allowing the vapors to condense and flow along the neck to a collection vessel placed underneath. In the chemical industry, a retort is an airtight vessel in which substances are heated for a chemical reaction producing gaseous products to be collected in a collection vessel or for further processing. Such industrial-scale retorts are used in shale oil extraction, the production of

charcoal Charcoal is a lightweight black carbon residue produced by strongly heating wood (or other animal and plant materials) in minimal oxygen to remove all water and volatile constituents. In the traditional version of this pyrolysis process, cal ...

and in the recovery of mercury in gold mining processes and hazardous waste. A process of heating oil shale to produce

shale oil Shale oil is an unconventional oil produced from oil shale rock fragments by pyrolysis, hydrogenation, or thermal dissolution. These processes convert the organic matter within the rock (kerogen) into synthetic oil and gas. The resulting oil ca ...

, oil shale gas, and

spent shale Spent shale or spent oil shale (also known as retorted shale) is a solid residue from the shale oil extraction process of producing synthetic shale oil from oil shale. It consists of inorganic compounds (minerals) and remaining organic matter kno ...

is commonly called retorting. Airtight vessels to apply pressure as well as heat are called

autoclaves An autoclave is a machine used to carry out industrial and scientific processes requiring elevated temperature and pressure in relation to ambient pressure and/or temperature. Autoclaves are used before surgical procedures to perform sterilizat ...

. In the food industry, pressure cookers are often referred to as retorts, meaning "

canning Canning is a method of food preservation in which food is processed and sealed in an airtight container (jars like Mason jars, and steel and tin cans). Canning provides a shelf life that typically ranges from one to five years, although u ...

retorts", for sterilization under high temperature (116–130 °C).

History

Retorts were widely used by alchemists, and images of retorts appear in many drawings and sketches of their laboratories. Before the advent of modern condensers, retorts were used by many prominent chemists, such as Antoine Lavoisier and

Jöns Berzelius Jöns is a Swedish given name and a surname. Notable people with the given name include: * Jöns Jacob Berzelius (1779–1848), Swedish chemist * Jöns Budde (1435–1495), Franciscan friar from the Brigittine monastery in NaantaliVallis Grati ...

. The earliest known use was by Islamic golden age chemist and philosopher Jabir ibn Hayyan c. one thousand years before European chemists. An early method for producing

phosphorus Phosphorus is a chemical element with the symbol P and atomic number 15. Elemental phosphorus exists in two major forms, white phosphorus and red phosphorus, but because it is highly reactive, phosphorus is never found as a free element on Ear ...

starts by roasting bones, and uses clay retorts encased in a very hot brick furnace to distill out the highly toxic product. The term ''retort'' comes by way of

Middle French Middle French (french: moyen français) is a historical division of the French language that covers the period from the 14th to the 16th century. It is a period of transition during which: * the French language became clearly distinguished from t ...

, but ultimately from

Latin Latin (, or , ) is a classical language belonging to the Italic branch of the Indo-European languages. Latin was originally a dialect spoken in the lower Tiber area (then known as Latium) around present-day Rome, but through the power of the ...

''retortus'', twisted back, for the shape of the neck.

Role in analytical chemistry

laboratory A laboratory (; ; colloquially lab) is a facility that provides controlled conditions in which scientific or technological research, experiments, and measurement may be performed. Laboratory services are provided in a variety of settings: physicia ...

use, due to advances in technology, especially the invention of the

Liebig condenser The Liebig condenser (, ) or straight condenser is a piece of laboratory equipment, specifically a condenser consisting of a straight glass tube surrounded by a water jacket. In typical laboratory operation, such as distillation, the condenser i ...

, retorts were largely considered to have been rendered obsolete as early as the beginning of the 20th century. However, some laboratory techniques that involve simple distillation and do not require sophisticated apparatus may use a retort as a substitute for more complex distillation equipment.

In biochar-pyrolysis industry

A retort is a reactor that has the ability to pyrolyze pile-wood, or wood logs over long and up to in diameter.Emrich, W. 'Handbook of Charcoal Making, the Traditional and Industrial Methods'. D. Reidel Pub. Co., Hingham, MA, 1985, p 296

References

External links

* {{Laboratory equipment Alchemical tools Laboratory glassware

History

Role in analytical chemistry

In biochar-pyrolysis industry

See also

References

External links