Lithium hydroxide is an
inorganic compound
In chemistry, an inorganic compound is typically a chemical compound that lacks carbon–hydrogen bonds, that is, a compound that is not an organic compound. The study of inorganic compounds is a subfield of chemistry known as '' inorganic chemis ...
with the
formula
In science, a formula is a concise way of expressing information symbolically, as in a mathematical formula or a ''chemical formula''. The informal use of the term ''formula'' in science refers to the general construct of a relationship betwe ...
LiOH. It can exist as anhydrous or hydrated, and both forms are white
hygroscopic
Hygroscopy is the phenomenon of attracting and holding water molecules via either absorption or adsorption from the surrounding environment, which is usually at normal or room temperature. If water molecules become suspended among the substance' ...
solids. They are soluble in water and slightly soluble in
ethanol
Ethanol (abbr. EtOH; also called ethyl alcohol, grain alcohol, drinking alcohol, or simply alcohol) is an organic compound. It is an alcohol with the chemical formula . Its formula can be also written as or (an ethyl group linked to a ...
. Both are available commercially. While classified as a
strong base, lithium hydroxide is the weakest known alkali metal hydroxide.
Production
The preferred feedstock is hard-rock
spodumene
Spodumene is a pyroxene mineral consisting of lithium aluminium inosilicate, Li Al( Si O3)2, and is a source of lithium. It occurs as colorless to yellowish, purplish, or lilac kunzite (see below), yellowish-green or emerald-green hiddenite, pri ...
, where the lithium content is expressed as %
lithium oxide.
Lithium carbonate route
Lithium hydroxide is often produced industrially from
lithium carbonate
Lithium carbonate is an inorganic compound, the lithium salt of carbonate with the formula . This white salt is widely used in the processing of metal oxides. It is listed on the World Health Organization's List of Essential Medicines because it c ...
in a
metathesis reaction with
calcium hydroxide
Calcium hydroxide (traditionally called slaked lime) is an inorganic compound with the chemical formula Ca( OH)2. It is a colorless crystal or white powder and is produced when quicklime (calcium oxide) is mixed or slaked with water. It has ma ...
:
:
The initially produced hydrate is dehydrated by heating under vacuum up to 180 °C.
Lithium sulfate route
An alternative route involves the intermediacy of
lithium sulfate
Lithium sulfate is a white inorganic salt with the formula Li2 S O4. It is the lithium salt of sulfuric acid.
Properties
Physical properties
Lithium sulfate is soluble in water, though it does not follow the usual trend of increasing solub ...
:
:α-
spodumene
Spodumene is a pyroxene mineral consisting of lithium aluminium inosilicate, Li Al( Si O3)2, and is a source of lithium. It occurs as colorless to yellowish, purplish, or lilac kunzite (see below), yellowish-green or emerald-green hiddenite, pri ...
→ β-spodumene
:β-spodumene + CaO → + ...
:
:
The main by-products are
gypsum
Gypsum is a soft sulfate mineral composed of calcium sulfate dihydrate, with the chemical formula . It is widely mined and is used as a fertilizer and as the main constituent in many forms of plaster, blackboard or sidewalk chalk, and drywa ...
and
sodium sulphate, which have some market value.
Commercial setting
According to Bloomberg,
Ganfeng Lithium Co. Ltd. (GFL or Ganfeng) and
Albemarle were the largest producers in 2020 with around 25kt/y, followed by Livent Corporation (FMC) and
SQM.
Significant new capacity is planned, to keep pace with demand driven by vehicle electrification. Ganfeng are to expand lithium chemical capacity to 85,000 tons, adding the capacity leased from Jiangte, Ganfeng will become the largest lithium hydroxide producer globally in 2021.
Albemarle's
Kemerton
Kemerton is a village and civil parish in Worcestershire in England. It lies at the extreme south of the county in the local government district of Wychavon. Until boundary changes in 1931, it formed part of neighbouring Gloucestershire, and ...
WA plant, originally planned to deliver 100kt/y has been scaled back to 50kt/y.
In 2020
Tianqi Lithium's, plant in
Kwinana, Western Australia is the largest producer, with a capacity of 48kt/y.
Applications
Lithium ion batteries
Lithium hydroxide is mainly consumed in the production of
cathode
A cathode is the electrode from which a conventional current leaves a polarized electrical device. This definition can be recalled by using the mnemonic ''CCD'' for ''Cathode Current Departs''. A conventional current describes the direction in whi ...
materials for
lithium ion batteries such as
lithium cobalt oxide () and
lithium iron phosphate. It is preferred over
lithium carbonate
Lithium carbonate is an inorganic compound, the lithium salt of carbonate with the formula . This white salt is widely used in the processing of metal oxides. It is listed on the World Health Organization's List of Essential Medicines because it c ...
as a precursor for
lithium nickel manganese cobalt oxides Lithium nickel manganese cobalt oxides (abbreviated Li-NMC, LNMC, or NMC) are mixed metal oxides of lithium, nickel, manganese and cobalt. They have the general formula LiNi''x''Mn''y''Co''z''O2. The most important representatives have a composition ...
.
Grease
A popular lithium grease thickener is
lithium 12-hydroxystearate, which produces a general-purpose lubricating
grease due to its high resistance to water and usefulness at a range of temperatures.
Carbon dioxide scrubbing
Lithium hydroxide is used in
breathing gas
A breathing gas is a mixture of gaseous chemical elements and compounds used for respiration. Air is the most common and only natural breathing gas, but other mixtures of gases, or pure oxygen, are also used in breathing equipment and enclosed ...
purification systems for
spacecraft
A spacecraft is a vehicle or machine designed to fly in outer space. A type of artificial satellite, spacecraft are used for a variety of purposes, including communications, Earth observation, meteorology, navigation, space colonization, ...
,
submarine
A submarine (or sub) is a watercraft capable of independent operation underwater. It differs from a submersible, which has more limited underwater capability. The term is also sometimes used historically or colloquially to refer to remotely op ...
s, and
rebreather
A rebreather is a breathing apparatus that absorbs the carbon dioxide of a user's exhaled breath to permit the rebreathing (recycling) of the substantially unused oxygen content, and unused inert content when present, of each breath. Oxygen i ...
s to remove
carbon dioxide
Carbon dioxide ( chemical formula ) is a chemical compound made up of molecules that each have one carbon atom covalently double bonded to two oxygen atoms. It is found in the gas state at room temperature. In the air, carbon dioxide is t ...
from exhaled gas by producing
lithium carbonate
Lithium carbonate is an inorganic compound, the lithium salt of carbonate with the formula . This white salt is widely used in the processing of metal oxides. It is listed on the World Health Organization's List of Essential Medicines because it c ...
and water:
:
or
:
The latter, anhydrous hydroxide, is preferred for its lower mass and lesser water production for respirator systems in spacecraft. One gram of anhydrous lithium hydroxide can remove 450 cm
3 of carbon dioxide gas. The monohydrate loses its water at 100–110 °C.
Precursor
Lithium hydroxide, together with
lithium carbonate
Lithium carbonate is an inorganic compound, the lithium salt of carbonate with the formula . This white salt is widely used in the processing of metal oxides. It is listed on the World Health Organization's List of Essential Medicines because it c ...
, is a key intermediates used for the production of other lithium compounds, illustrated by its use in the production of
lithium fluoride:
:
Other uses
It is also used in
ceramic
A ceramic is any of the various hard, brittle, heat-resistant and corrosion-resistant materials made by shaping and then firing an inorganic, nonmetallic material, such as clay, at a high temperature. Common examples are earthenware, porcelain, ...
s and some
Portland cement
Portland cement is the most common type of cement in general use around the world as a basic ingredient of concrete, mortar, stucco, and non-specialty grout. It was developed from other types of hydraulic lime in England in the early 19t ...
formulations, where it is also used to suppress ASR (
concrete cancer
Concrete is a composite material composed of fine and coarse aggregate bonded together with a fluid cement (cement paste) that hardens (cures) over time. Concrete is the second-most-used substance in the world after water, and is the most w ...
).
Lithium hydroxide (
isotopically enriched in
lithium-7) is used to alkalize the reactor coolant in
pressurized water reactor
A pressurized water reactor (PWR) is a type of light-water nuclear reactor. PWRs constitute the large majority of the world's nuclear power plants (with notable exceptions being the UK, Japan and Canada). In a PWR, the primary coolant (water) i ...
s for corrosion control.
It is good radiation protection against free neutrons.
Price
In 2012, the price of lithium hydroxide was about $5-6/kg.
In December 2020 it had risen to $9/kg
On 18 March 2021 the price had risen to US$11.50/kg
See also
*
Soda lime
Soda lime is a mixture of NaOH and CaO chemicals, used in granular form in closed breathing environments, such as general anaesthesia, submarines, rebreathers and recompression chambers, to remove carbon dioxide from breathing gases to prevent ...
References
External links
* (anhydrous)
* (monohydrate)
{{Authority control
Lithium compounds
Hydroxides
*