Lithium perchlorate is the

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 chemist ...

with the formula LiClO₄. This white or colourless crystalline salt is noteworthy for its high solubility in many solvents. It exists both in anhydrous form and as a

trihydrate 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 underst ...

Applications

Inorganic chemistry

Lithium perchlorate is used as a source of

oxygen Oxygen is the chemical element with the symbol O and atomic number 8. It is a member of the chalcogen group in the periodic table, a highly reactive nonmetal, and an oxidizing agent that readily forms oxides with most elements as wel ...

in some

chemical oxygen generator A chemical oxygen generator is a device that releases oxygen via a chemical reaction. The oxygen source is usually an inorganic superoxide, chlorate, or perchlorate; ozonides are a promising group of oxygen sources. The generators are usually igni ...

s. It decomposes at about 400 °C, yielding

lithium chloride Lithium chloride is a chemical compound with the formula Li Cl. The salt is a typical ionic compound (with certain covalent characteristics), although the small size of the Li+ ion gives rise to properties not seen for other alkali metal chlor ...

and

: : LiClO₄ → LiCl + 2 O₂ Over 60% of the mass of the lithium perchlorate is released as oxygen. It has both the highest oxygen to weight and oxygen to volume ratio of all practical

perchlorate A perchlorate is a chemical compound containing the perchlorate ion, . The majority of perchlorates are commercially produced salts. They are mainly used as oxidizers for pyrotechnic devices and to control static electricity in food packaging. Per ...

salts.

Organic chemistry

LiClO₄ is highly soluble in organic solvents, even diethyl ether. Such solutions are employed in Diels–Alder reactions, where it is proposed that the

Lewis acid A Lewis acid (named for the American physical chemist Gilbert N. Lewis) is a chemical species that contains an empty orbital which is capable of accepting an electron pair from a Lewis base to form a Lewis adduct. A Lewis base, then, is any sp ...

ic Li⁺ binds to Lewis basic sites on the dienophile, thereby accelerating the reaction. Lithium perchlorate is also used as a

co-catalyst Catalysis () is the process of increasing the rate of a chemical reaction by adding a substance known as a catalyst (). Catalysts are not consumed in the reaction and remain unchanged after it. If the reaction is rapid and the catalyst recyc ...

in the coupling of α,β-unsaturated carbonyls with aldehydes, also known as the

Baylis–Hillman reaction The Baylis–Hillman reaction is a carbon-carbon bond forming reaction between the α-position of an activated alkene and a carbon electrophile such as an aldehyde. Employing a nucleophilic catalyst, such as a tertiary amine and phosphine, this rea ...

. Solid lithium perchlorate is found to be a mild and efficient Lewis acid for promoting cyanosilylation of carbonyl compounds under neutral conditions.

Batteries

Lithium perchlorate is also used as an

electrolyte An electrolyte is a medium containing ions that is electrically conducting through the movement of those ions, but not conducting electrons. This includes most soluble salts, acids, and bases dissolved in a polar solvent, such as water. Upon dis ...

salt in

lithium-ion batteries A lithium-ion or Li-ion battery is a type of rechargeable battery which uses the reversible reduction of lithium ions to store energy. It is the predominant battery type used in portable consumer electronics and electric vehicles. It also se ...

. Lithium perchlorate is chosen over alternative salts such as

lithium hexafluorophosphate Lithium hexafluorophosphate is an inorganic compound with the formula Li PF6. It is a white crystalline powder. Production LiPF6 is manufactured by reacting phosphorus pentachloride with hydrogen fluoride and lithium fluoride :PCl5 + LiF + 5 ...

lithium tetrafluoroborate Lithium tetrafluoroborate is an inorganic compound with the formula Li BF4. It is a white crystalline powder. It has been extensively tested for use in commercial secondary batteries, an application that exploits its high solubility in nonpolar ...

when its superior

electrical impedance In electrical engineering, impedance is the opposition to alternating current presented by the combined effect of resistance and reactance in a circuit. Quantitatively, the impedance of a two-terminal circuit element is the ratio of the comp ...

conductivity Conductivity may refer to: *Electrical conductivity, a measure of a material's ability to conduct an electric current **Conductivity (electrolytic), the electrical conductivity of an electrolyte in solution **Ionic conductivity (solid state), elec ...

hygroscopicity 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 substanc ...

, and anodic stability properties are of importance to the specific application. However, these beneficial properties are often overshadowed by the electrolyte's strong

oxidizing Redox (reduction–oxidation, , ) is a type of chemical reaction in which the oxidation states of substrate change. Oxidation is the loss of electrons or an increase in the oxidation state, while reduction is the gain of electrons or a d ...

properties, making the electrolyte reactive toward its

solvent A solvent (s) (from the Latin '' solvō'', "loosen, untie, solve") is a substance that dissolves a solute, resulting in a solution. A solvent is usually a liquid but can also be a solid, a gas, or a supercritical fluid. Water is a solvent for ...

at high temperatures and/or high

current Currents, Current or The Current may refer to: Science and technology * Current (fluid), the flow of a liquid or a gas ** Air current, a flow of air ** Ocean current, a current in the ocean *** Rip current, a kind of water current ** Current (stre ...

loads. Due to these hazards the battery is often considered unfit for industrial applications.

Biochemistry

Concentrated solutions of lithium perchlorate (4.5 mol/L) are used as a

chaotropic agent A chaotropic agent is a molecule in water solution that can disrupt the hydrogen bonding network between water molecules (i.e. exerts chaotropic activity). This has an effect on the stability of the native state of other molecules in the solution, ...

to denature

protein Proteins are large biomolecules and macromolecules that comprise one or more long chains of amino acid residues. Proteins perform a vast array of functions within organisms, including catalysing metabolic reactions, DNA replication, respo ...

Production

Lithium perchlorate can be manufactured by reaction of

sodium perchlorate Sodium perchlorate is the inorganic compound with the chemical formula Na ClO4. It is a white crystalline, hygroscopic solid that is highly soluble in water and in alcohol. It is usually encountered as the monohydrate. The compound is noteworthy ...

with

. It can be also prepared by electrolysis of lithium chlorate at 200 mA/cm² at temperatures above 20 °C.Helmut Vogt, Jan Balej, John E. Bennett, Peter Wintzer, Saeed Akbar Sheikh, Patrizio Gallone "Chlorine Oxides and Chlorine Oxygen Acids" in Ullmann's Encyclopedia of Industrial Chemistry 2002, Wiley-VCH.

Safety

Perchlorate A perchlorate is a chemical compound containing the perchlorate ion, . The majority of perchlorates are commercially produced salts. They are mainly used as oxidizers for pyrotechnic devices and to control static electricity in food packaging. Per ...

s often give explosive mixtures with organic compounds, finely divided metals, and other reducing agents.

References

External links

WebBook page for LiClO4
{{Perchlorates Perchlorates Lithium salts Oxidizing agents Electrolytes