Trona (trisodium hydrogendicarbonate

dihydrate In chemistry, a hydrate is a substance that contains water or its constituent elements. The chemical state of the water varies widely between different classes of hydrates, some of which were so labeled before their chemical structure was understo ...

, also

sodium sesquicarbonate Sodium sesquicarbonate (systematic name: trisodium hydrogendicarbonate) Na3H(CO3)2 is a double salt of sodium bicarbonate and sodium carbonate (NaHCO3 · Na2CO3), and has a needle-like crystal structure. However, the term is also applied to an ...

dihydrate, Na₂CO₃·NaHCO₃·2H₂O) is a non- marine

evaporite An evaporite () is a water- soluble sedimentary mineral deposit that results from concentration and crystallization by evaporation from an aqueous solution. There are two types of evaporite deposits: marine, which can also be described as oce ...

mineral In geology and mineralogy, a mineral or mineral species is, broadly speaking, a solid substance with a fairly well-defined chemical composition and a specific crystal structure that occurs naturally in pure form.John P. Rafferty, ed. (2011): Mi ...

. It is mined as the primary source of

sodium carbonate Sodium carbonate (also known as washing soda, soda ash, sal soda, and soda crystals) is the inorganic compound with the formula and its various hydrates. All forms are white, odourless, water-soluble salts that yield alkaline solutions in water ...

in the United States, where it has replaced the

Solvay process The Solvay process or ammonia–soda process is the major industrial process for the production of sodium carbonate (soda ash, Na2CO3). The ammonia–soda process was developed into its modern form by the Belgian chemist Ernest Solvay during the ...

used in most of the rest of the world for sodium carbonate production. Turkey is also a major producer.

Etymology

The word entered English by way of either Swedish () or Spanish (), with both possible sources having the same meaning as in English: the mineral

natron Natron is a naturally occurring mixture of sodium carbonate decahydrate ( Na2CO3·10H2O, a kind of soda ash) and around 17% sodium bicarbonate (also called baking soda, NaHCO3) along with small quantities of sodium chloride and sodium sulfate. ...

from North Africa. Both the Spanish and Swedish terms derive from the Arabic ''trōn'', which in turn derives from Arabic ''natron'' and Hebrew (''natruna''), which comes from

ancient Greek Ancient Greek (, ; ) includes the forms of the Greek language used in ancient Greece and the classical antiquity, ancient world from around 1500 BC to 300 BC. It is often roughly divided into the following periods: Mycenaean Greek (), Greek ...

(''nitron''), derived ultimately from

ancient Egyptian Ancient Egypt () was a cradle of civilization concentrated along the lower reaches of the Nile River in Northeast Africa. It emerged from prehistoric Egypt around 3150BC (according to conventional Egyptian chronology), when Upper and Lower E ...

''ntry'' (or ''nitry'’).

Natural deposits

Trona is found at

Owens Lake Owens Lake is a dry lake in the Owens Valley on the eastern side of the Sierra Nevada in Inyo County, California. It is about south of Lone Pine. Unlike most dry lakes in the Basin and Range Province that have been dry for thousands of years, ...

and

Searles Lake Searles Lake is an Endorheic basin, endorheic dry lake in the Searles Valley of the Mojave Desert, in northwestern San Bernardino County, California. The lake in the past was also called Slate Range Lake and Borax Lake. The mining community of ...

California California () is a U.S. state, state in the Western United States that lies on the West Coast of the United States, Pacific Coast. It borders Oregon to the north, Nevada and Arizona to the east, and shares Mexico–United States border, an ...

; the

Green River Formation The Green River Formation is an Eocene geologic formation that records the sedimentation in a group of intermountain lakes in three basins along the present-day Green River (Colorado River), Green River in Colorado, Wyoming, and Utah. The sedimen ...

Wyoming Wyoming ( ) is a landlocked U.S. state, state in the Mountain states, Mountain West subregion of the Western United States, Western United States. It borders Montana to the north and northwest, South Dakota and Nebraska to the east, Idaho t ...

and

Utah Utah is a landlocked state in the Mountain states, Mountain West subregion of the Western United States. It is one of the Four Corners states, sharing a border with Arizona, Colorado, and New Mexico. It also borders Wyoming to the northea ...

; the

Makgadikgadi Pans The Makgadikgadi Pan (Tswana pronunciation ), a salt pan situated in the middle of the dry savanna of north-eastern Botswana, is one of the largest salt flats in the world. The pan is all that remains of the formerly enormous Lake Makgadik ...

Botswana Botswana, officially the Republic of Botswana, is a landlocked country in Southern Africa. Botswana is topographically flat, with approximately 70 percent of its territory part of the Kalahari Desert. It is bordered by South Africa to the sou ...

and in the

Nile Valley The Nile (also known as the Nile River or River Nile) is a major north-flowing river in northeastern Africa. It flows into the Mediterranean Sea. The Nile is the longest river in Africa. It has historically been considered the longest river i ...

Egypt Egypt ( , ), officially the Arab Republic of Egypt, is a country spanning the Northeast Africa, northeast corner of Africa and Western Asia, southwest corner of Asia via the Sinai Peninsula. It is bordered by the Mediterranean Sea to northe ...

. The trona near

Green River, Wyoming Green River is a city in and the county seat of Sweetwater County, Wyoming, United States, in the southwestern part of the state. The population was 11,825 at the 2020 census. It is the 7th most populous city in Wyoming. History The townsi ...

, is the largest known deposit in the world and lies in layered

deposits below ground, where the trona was deposited in a lake during the

Paleogene The Paleogene Period ( ; also spelled Palaeogene or Palæogene) is a geologic period and system that spans 43 million years from the end of the Cretaceous Period Ma (million years ago) to the beginning of the Neogene Period Ma. It is the fir ...

Period.Wyoming Mining Association (2017)
Wyoming Mining Association: Trona Mining
Wyoming Mining Association. Retrieved on 2017-10-25. Trona has also been mined at

Lake Magadi Lake Magadi is the southernmost lake in the Kenyan Rift Valley, lying in a catchment of faulted volcanic rocks, north of Tanzania's Lake Natron. During the dry season, it is 80% covered by soda and is known for its wading birds, including f ...

in the

Kenyan Rift Valley The Great Rift Valley is part of an intra-continental ridge system that runs through Kenya from north to south. It is part of the Gregory Rift, the eastern branch of the East African Rift, which starts in Tanzania to the south and continues no ...

for nearly 100 years. The northern part of

Lake Natron Lake Natron is a salt lake, salt or soda lake, alkaline lake located in north Ngorongoro District of Arusha Region in Tanzania with its far northern end crossing into Kenya. It is in the Gregory Rift, which is the eastern branch of the East A ...

is covered by a 1.5 m thick trona bed, and occurs in 'salt' pans in the

Etosha National Park Etosha National Park is a national park in northwestern Namibia and one of the largest national parks in Africa. It was proclaimed a game reserve in March 1907 in Ordinance 88 by the Governor of German South West Africa, Friedrich von Lindequist. ...

Namibia Namibia, officially the Republic of Namibia, is a country on the west coast of Southern Africa. Its borders include the Atlantic Ocean to the west, Angola and Zambia to the north, Botswana to the east and South Africa to the south; in the no ...

. The Beypazari region in the

Ankara Province Ankara Province (, ) is a province and metropolitan municipality of Turkey with the capital city Ankara. Its area is 25,632 km2, and its population is 5,782,285 (2022). History The site of the modern city has been home to settlements ...

Turkey Turkey, officially the Republic of Türkiye, is a country mainly located in Anatolia in West Asia, with a relatively small part called East Thrace in Southeast Europe. It borders the Black Sea to the north; Georgia (country), Georgia, Armen ...

has some 33 trona beds in two fault-bound lensoid bodies in and above

oil shale Oil shale is an organic-rich Granularity, fine-grained sedimentary rock containing kerogen (a solid mixture of Organic compound, organic chemical compounds) from which liquid hydrocarbons can be produced. In addition to kerogen, general compos ...

s of the Lower Hirka Formation (16 in the lower and 17 in the upper body). The Wucheng basin trona mine,

Henan Province Henan; alternatively Honan is a province in Central China. Henan is home to many heritage sites, including Yinxu, the ruins of the final capital of the Shang dynasty () and the Shaolin Temple. Four of the historical capitals of China, Luo ...

China China, officially the People's Republic of China (PRC), is a country in East Asia. With population of China, a population exceeding 1.4 billion, it is the list of countries by population (United Nations), second-most populous country after ...

has some 36 trona beds (693–974 m deep), the lower 15 beds are 0.5–1.5 m thick, thickest 2.38 m; the upper 21 beds are 1–3 m thick, with a maximum of 4.56 m hosted and underlain by

dolomitic Dolomite () is an anhydrous carbonate mineral composed of calcium magnesium carbonate, ideally The term is also used for a sedimentary carbonate rock composed mostly of the mineral dolomite (see Dolomite (rock)). An alternative name sometimes ...

oil shales of the Wulidui Formation. Trona has also been found in

magmatic Magma () is the molten or semi-molten natural material from which all igneous rocks are formed. Magma (sometimes colloquially but incorrectly referred to as ''lava'') is found beneath the surface of the Earth, and evidence of magmatism has also ...

environments. Research has shown that trona can be formed by auto

metasomatic Metasomatism (from the Greek μετά ''metá'' "change" and σῶμα ''sôma'' "body") is the chemical alteration of a rock by hydrothermal and other fluids. It is traditionally defined as metamorphism which involves a change in the chemical com ...

reactions of late-magmatic fluids or melts (or

supercritical fluid A supercritical fluid (SCF) is a substance at a temperature and pressure above its critical point, where distinct liquid and gas phases do not exist, but below the pressure required to compress it into a solid. It can effuse through porous sol ...

-melt mixtures), with earlier crystallized rocks within the same

plutonic Intrusive rock is formed when magma penetrates existing rock, crystallizes, and solidifies underground to form ''intrusions'', such as batholiths, dikes, sills, laccoliths, and volcanic necks.Intrusive RocksIntrusive rocks accessdate: Marc ...

complex, or by large-scale

vapor In physics, a vapor (American English) or vapour (Commonwealth English; American and British English spelling differences#-our, -or, see spelling differences) is a substance in the gas phase at a temperature lower than its critical temperature,R ...

unmixing in the very final stages of magmatism.

Crystal structure

The

crystal structure In crystallography, crystal structure is a description of ordered arrangement of atoms, ions, or molecules in a crystalline material. Ordered structures occur from intrinsic nature of constituent particles to form symmetric patterns that repeat ...

of trona was first determined by Brown et al. (1949). The structure consists of units of 3 edge-sharing sodium polyhedra (a central octahedron flanked by septahedra), cross-linked by carbonate groups and

hydrogen bond In chemistry, a hydrogen bond (H-bond) is a specific type of molecular interaction that exhibits partial covalent character and cannot be described as a purely electrostatic force. It occurs when a hydrogen (H) atom, Covalent bond, covalently b ...

s. Bacon and Curry (1956) refined the structure determination using two-dimensional single-crystal

neutron diffraction Neutron diffraction or elastic neutron scattering is the application of neutron scattering to the determination of the atomic and/or magnetic structure of a material. A sample to be examined is placed in a beam of Neutron temperature, thermal or ...

, and suggested that the hydrogen atom in the symmetric (HC₂O₆)³⁻ anion is disordered. The environment of the disordered H atom was later investigated by Choi and Mighell (1982) at 300 K with three-dimensional single-crystal neutron diffraction: they concluded that the H atom is dynamically disordered between two equivalent sites, separated from one another by 0.211(9) Å. The dynamically disordered H atom was reinvestigated at low temperature by O'Bannon et al. 2014 and they concluded that it does not order at temperatures as low as 100K.

Uses

* Trona is a common source of

soda ash Sodium carbonate (also known as washing soda, soda ash, sal soda, and soda crystals) is the inorganic compound with the formula and its various hydrates. All forms are white, odourless, water-soluble salts that yield alkaline solutions in water ...

, which is a significant economic commodity because of its applications in manufacturing glass, chemicals, paper, detergents, and textiles. * It is used to condition water. * It is used to remove sulfur from both flue gases and

lignite Lignite (derived from Latin ''lignum'' meaning 'wood'), often referred to as brown coal, is a soft, brown, combustible sedimentary rock formed from naturally compressed peat. It has a carbon content around 25–35% and is considered the lowest ...

coals. * It is a product of

carbon sequestration Carbon sequestration is the process of storing carbon in a carbon pool. It plays a crucial role in Climate change mitigation, limiting climate change by reducing the amount of Carbon dioxide in Earth's atmosphere, carbon dioxide in the atmosphe ...

of flue gases. * It is also used as a food additive.

Mining operations

Rio Tinto – Owens Lake Rio or Río is the Portuguese and Spanish word for "river". The word also exists in Italian, but is largely obsolete and used in a poetical or literary context to mean "stream". Rio, RIO or Río may also refer to: Places United States * Rio, Fl ...

Magadi Soda Company The Magadi Soda Company manufactures soda ash at the Kenyan town of Magadi, Kenya, Magadi, which is in southwestern Kenya. It is the largest manufacturer of soda ash in Africa. The company was founded in 1911 and mines trona from Lake Magadi, in ...

* Searles Valley Minerals Inc. *

Solvay Solvay may refer to: Companies and organizations * Solvay Brussels School of Economics and Management, Brussels, Belgium * Solvay Institute of Sociology, Brussels, Belgium, part of the Université Libre de Bruxelles * Solvay Process Company (1880 ...

Tata Chemicals Tata Chemicals Limited is an Indian multinational corporation with interests in chemicals, crop protection and specialty chemistry products. The company is headquartered in Mumbai and has operations across India, Europe, North America and Afric ...

Genesis Alkali Genesis may refer to: Religion * Book of Genesis, the first book of the biblical scriptures of both Judaism and Christianity, describing the creation of the Earth and of humankind * Genesis creation narrative, the first several chapters of the Bo ...

formerly

Tronox Tronox Limited is an American worldwide chemical company involved in the titanium products industry with approximately 6,500 employees. Following its acquisition of the mineral sands business formerly belonging to South Africa's Exxaro Resources, ...

Alkali ''formerly

FMC Corporation FMC Corporation is an American chemical manufacturing company headquartered in Philadelphia, Pennsylvania, which originated as an insecticide producer in 1883 and later diversified into other industries. In 1941 at the beginning of US involvemen ...

'' *

General Chemical Tata Chemicals Limited is an Indian multinational corporation with interests in chemicals, crop protection and specialty chemistry products. The company is headquartered in Mumbai and has operations across India, Europe, North America and Afric ...

Ciner Wyoming The Ciner Wyoming LCC is a mining and chemical industry company based in Wyoming, United States, producing natural soda ash from trona. The initial company was founded in 1962. Since 2015, it is under the control of the Turkish Ciner Holding. Bac ...

''formerly

OCI Chemical Corp. OCI may refer to: Businesses and organizations * OCI (company), green energy and chemical company, South Korea * Oakwood Collegiate Institute, Toronto, Canada * Office of Criminal Investigations of the U.S. Food and Drug Administration * Olympic ...

'' * ANSAC *

Eti Soda The Eti Soda Inc. is a chemical industry company in Ankara Province, Turkey, producing natural soda ash and baking soda from trona. It was founded in 1998, and the production started in 2009. The company's main shareholder is Ciner Group. Backg ...

, Turkey *

Kazan Soda Elektrik The Kazan Soda Elektrik, full name Kazan Soda Elektrik Üretim A.Ş., is a chemical industry and electric energy company in Ankara Province, Turkey producing natural soda ash and baking soda from trona. The company is a subsidiary of Ciner Holding ...

, Turkey *

Church & Dwight Church & Dwight Co., Inc. is an American consumer goods company focusing on personal care, household products, and specialty products. The company was founded in 1847 and is headquartered in Ewing, New Jersey. It is the parent company of well-kno ...

– Green River Mine *

Intrepid Potash Intrepid Potash, Inc. (), based in Denver, Colorado, is a fertilizer manufacturer. The company is the largest producer of potassium chloride, also known as muriate of potash, in the United States. It owns three mines, all in the Western U.S., nea ...

Simplot The J. R. Simplot Company (commonly referred to as Simplot) is an agribusiness company headquartered in Boise, Idaho, United States. History Simplot was founded in 1929 by 20-year-old John Richard Simplot near the agricultural community of D ...

References