Lithium, an element of unique physical and chemical properties, is useful in a wide range of applications as the metal, as the lithium ion in inorganic salts, and as the more covalent species in inorganic compounds. The largest uses of lithium compounds are in traditional areas such as the preparation of glass, glass‐ceramics, and enamels; in aluminum cell broth; in the preparation of lithium greases; and as polymerization initiators. Lithium compounds are also employed as psychopharmacological agents and in organic synthesis, catalysis, absorption, air conditioning, photographic processing, and in batteries. The use of organic lithium compounds as industrial catalysts and the consumption of various lithium compounds in batteries are the most rapidly expanding markets. The various lithium mineral and brine resources are reviewed along with the processes for lithium extraction and recovery. Manufacturing processes, properties, health and safety factors, and applications for lithium metal and lithium compounds are discussed.
Fluoroboric acid and the fluoroborates are commercially important to a variety of industries. The acid is used in plating circuits, in metal finishing, in the production of aluminum, and as an acid catalyst. Main group metal and ammonium fluoroborates find use as fluxes, as catalysts, and in flame‐retardant manufacture. Transition‐ and other heavy‐metal fluoroborate salts are used in the plating industry and as catalysts. Properties and manufacture are described.
There are a considerable number of stable crystalline salts of the ammonium ion, \documentclass{article}\pagestyle{empty}\begin{document}${{\rm{NH}}^{+}_{4}}$\end{document} . Several are of commercial importance because of large‐scale consumption in fertilizer and industrial markets. These salts are often isomorphous and have similar solubility in water. Compounds in which the ammonium ion is combined with a large, uninegative anion are usually the most stable. Ammonium salts containing a small, highly charged anion generally dissociate easily into ammonia and the free acid. Both normal or neutral ammonium acetate, NH 4 C 2 H 3 O 2 , and the acid salt are known. Ammonium bicarbonate is easily formed. It is produced as both food and standard grade. Normal ammonium carbonate, a crystalline solid, is the principal ingredient of smelling salts because of its characteristic strong ammonia odor. Diammonium citrate is made by neutralization of citric acid. The crystalline or granular product is used as a chemical reagent and as a diuretic. Ammonium chloride, ammonium bromide, and ammonium iodide are crystalline, ionic compounds that exhibit high vapor pressures at elevated temperatures and sublime readily. Aqueous solutions of ammonium halides are acidic. A process based on metathesis or double decomposition is generally preferred for manufacture of ammonium chloride. Several commercial grades are available. Ammonium chloride is used as a nitrogen source for fertilization of rice, wheat, and other crops. Ammonium chloride serves as an electrolyte in the manufacture of drycell batteries, is also used to make quarrying explosives. Ammonium bromide and iodide are manufactured either by the reaction of ammonia with the corresponding hydrohalic acid or by the reaction of ammonia with elemental bromine or iodine. Ammonium bromide is used to manufacture chemical intermediates, and in photographic chemicals. There are two fluoride salts of ammonia: ammonium fluoride, principally a laboratory reagent, and ammonium bifluoride, used primarily as a less hazardous substitute for hydrofluoric acid. In addition to frosting glass, uses of the bifluoride include removing scale from boiler tubes and defouling oil wells. Properties, manufacture, and applications are described. Ammonium nitrate, a white, crystalline salt that is highly soluble in water, is the most commercially important ammonium compound both in terms of production volume and usage. It is the principal component of most industrial explosives and nonmilitary blasting compositions; however, it is used primarily as a nitrogen fertilizer. Ammonium nitrate is considered a very stable salt, but when heated to temperatures from 200 to 230°C, exothermic decomposition occurs. The reaction is rapid, but can be controlled. Above 230°C, exothermic elimination of N 2 and NO 2 begin, and a final violent exothermic reaction occurs with great rapidity when ammonium nitrate detonates. When used in blasting, ammonium nitrate is mixed with fuel oil and sometimes sensitizers such as powdered aluminum. Modern commercial processes for ammonium nitrate rely almost exclusively on the neutralization of nitric acid with ammonia. Ammonium nitrate can be considered a safety material if treated and handled properly. Potential hazards include those associated with fire, decomposition accompanied by generation of toxic fumes, and explosion. Many plants outside of North America prill or granulate a mixture of ammonium nitrate and calcium carbonate. Production of this mixture, often called calcium ammonium nitrate, essentially removes any explosion hazard. Ammonium sulfate, a white, soluble, crystalline salt, is produced from the direct neutralization of sulfuric acid with ammonia. Used as a fertilizer, it is valued both for its nitrogen content and for its readily available sulfur content. Ammonium sulfide and ammonium hydrosulfide are used by the textile industry. Most quaternary ammonium compounds produced in the United States are formulated into consumer products. The largest markets for quaternaries are fabric softening, hair care, bactericidal and germicidal applications, and for manufacture of organoclays. When one of the alkyl groups contains ∼ 10 carbon atoms, the molecules exhibit surface‐active properties. Physical properties are determined by the chemical structure of the material. Reactions include eliminations, displacements, and rearrangements. There are also many biologically important quaternaries. Most quaternaries are biodegradable. Quaternaries are prepared by the reaction of a tertiary amine with an alkylating agent. Commercial production from natural fats and oils, α‐olefins, and fatty alcohols is described. Quaternized esteramines are gaining market share in Western Europe. Other classes of quaternaries include phase‐transfer catalysts, polyamine‐based quaternaries, and perfluorinated quaternaries.
The boron trihalides boron trifluoride, BF 3 , boron trichloride, BCl 3 , and boron tribromide, BBr 3 , are important industrial chemicals having increased usage as Lewis acid catalysts and in chemical vapor deposition (CVD) processes. Boron halides are widely used in the laboratory as catalysts and reagents in numerous types of organic reactions and as starting material for many organoboron and inorganic boron compounds. Reactions of boron trihalides that are of commercial importance are those of BCl 3 and, to a lesser extent, BBr 3 , with gases in chemical vapor deposition (CVD). Boron trichloride is prepared on a large scale by the reaction of Cl 2 and a heated mixture of borax, , and crude oil residue in a rotary kiln heated to 1038°C. Boron trihalides, BX 3 , are trigonal planar molecules which are ( sp ) 2 hybridized. The X–B–X angles are 120°. The boron trihalides are strong Lewis acids; however, the order of relative acid strengths, , is contrary to that expected based on the electronegativities and atomic sizes of the halogen atoms. Boron tribromide is produced on a large scale by the reaction of Br 2 and granulated B 4 C at 850–1000°C or by the reaction of HBr with CaB 6 at high temperatures. Approximately 75–95% of the BCl 3 consumed in the United States is used to prepare boron filaments by CVD. Another important use of BCl 3 is as a Friedel‐Crafts catalyst in various polymerization, alkylation, and acylation reactions, and in other organic syntheses. BCl 3 is also used for the production of halosilanes, in the preparation of many boron compounds and in the production of optical wave guides. BBr 3 is used in the manufacture of isotopically enriched crystalline boron, as a Friedel‐Crafts catalyst in various polymerization, alkylation, and acylation reactions, and in semiconductor doping and etching. Boron subhalides are binary compounds of boron and the halogens, where the atomic ratio of halogen to boron is less than 3. The boron monohalides and boron dihalide radicals have been studied. Diboron tetraflouride, B 2 F 4 , diboron tetrachloride, B 2 Cl 4 , diboron tetrabromide, B 2 Br 4 , and diborontetraiodide, B 2 I 4 , are well‐known but thermally unstable compounds. Fluoroboric acid and the fluoroborates are commercially important to a variety of industries. The acid is used in plating circuits, in metal finishing, in the production of aluminum, and as an acid catalyst. Main group metal and ammonium fluoroborates find use as fluxes, as catalysts, and in flame‐retardant manufacture. Transition‐ and other heavy‐metal fluoroborate salts are used in the plating industry and as catalysts. Properties and manufacture are described.
Lithium fluoride is used primarily in the ceramic industry to reduce firing temperatures and improve resistance to thermal shock, abrasion, and acid attack. It is also used in flux compositions with other fluorides, chlorides, and borates for metal joining, and is an essential component of the fluorine cell electrolyte. Properties are described.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.
customersupport@researchsolutions.com
10624 S. Eastern Ave., Ste. A-614
Henderson, NV 89052, USA
Copyright © 2024 scite LLC. All rights reserved.
Made with 💙 for researchers
Part of the Research Solutions Family.