Fluorine economic importance

Halides are compounds that include one of the halogen elements fluorine, chlorine, bromine, or iodine. The simplest halides are combinations of one element, such as sodium (Na), with a halogen element, such as chlorine (Cl). Complex halides combine two or more elements with a halogen, and some contain water. Some halides are economically important minerals, such as halite (common salt), fluorite (fluorine), and chlorargyrite (silver ore). 

Much of the work done in Fluorine Chemistry is financed or motivated from the economic benefits of industrial applications, many of which are outlined in the final two chapters of this volume. But, as we all know, the economic importance of what we fluorine chemists do cannot be easily foretold. What is important, is that the discoveries that are made should be related as firmly as possible to fundamental chemical and physical concepts. We see much of that kind of correlation in this book. 

Although NF3 has been known since 1928, it first became of commercial interest in the late 1950s. Only two processes are of technical and economic importance for the large-scale production of NF3 (1) the electrolysis of molten ammonium hydrogen difluoride, and (2) the direct fluorination of ammonia in the presence of molten ammonium hydrogen difluoride. The electrolytic process has also been recommended and widely used for the preparation of NF3 in the laboratory. 

Bertrandite, 4BeO 2Si02 H20, became of importance ia 1969 when the deposits of Spor Mountain ia the Topa2 district of Utah were commercially Opened. These deposits are befieved to have been derived from fluorine-rich hydrothermal solutions at shaUow depths (2). Whereas economical beneficiation of these ores averagiag < 1% BeO has not been achieved, these deposits are commercially viable because of the large reserves present. 

Cholesterol lowering drugs are indicated for the prevention and treatment of atherosclerosis. There are three families of these dmgs inhibitors of HMG-CoA reductase (statins), inhibitors of cholesterol transport protein, and inhibitors of cholesteryl ester transfer protein (CETP). They are important drugs from an economical point of view. Among them, several are fluorinated. 

The rare earths (see table II) have a marked geochemical affinity for fluorine, calcium, titanium, niobium, zirconium, and the phosphate and carbonate ions. The most important, from an economic viewpoint, are the carbonatites and the phosphates. 

Direct fluorination of organic compounds using fluorine is an important methodology when considering safety, environmental and recycling problems. Fluorine can be fed into the reactor from a cylinder for the direct fluorination procedure, but this method has economic and safety disadvantages. Electrochemical generation of fluorine has recently been adopted for fluorination even in the laboratory. It can be operated easily and safely, because operational difficulties have been improved. 

The fluoride ion, at proper levels of intake, assists in the prevention of dental caries. When children under 9 years of age consume drinking water containing 1 part per million of fluorine, the teeth have fewer dental caries in childhood, adolescence, and throughout life. This has led to the fluoridation of water supplies in many countries. Fluoridation of water supplies to bring the concentration of fluoride to 1 ppm (one part of fluorine to a million parts of water) has proved to be safe, economical, and an efficient way to reduce tooth decay—a highly important public health measure in areas where natural water supplies do not contain this amount. Extensive medical and public health studies have clearly demonstrated the safety and nutritional advantages that result from fluoridation of water supplies. In communities in which fluoridation has been introduced, the incidence of tooth decay in children has been decreased by 50% or more. 

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