Fluorine, production

Raw Material. The principal raw material for fluorine production is high purity anhydrous hydrofluoric acid. Each kilogram of fluorine generated requires ca 1.1 kg HE. Only a small portion of the hydrofluoric acid produced ia the United States is consumed ia fluorine production. The commercial grade is acceptable for use as received, provided water content is less than 0.02%. Typical specifications for hydrofluoric acid are... 

Fig. 4. Equipment flow sheet of elemental fluorine production and liquefaction plant, 9 t/d capacity. Step 1 purging residual F2 at rates indicated all but a trace of residual F2 is removed in 15min N2 purge is maintained for 1 h to remove last traces. Step 2 HF removal at rates indicated all but a trace of HF is...

Price. The 1993 U.S. price for fluorine in cylinders was 109/kg for 2.2 kg and 260/kg for 0.7 kg cylinders. The price in large volumes is determined by (/) the price of hydrofluoric acid (2) power costs, ca 4.5 kWh electricity is required for each kilogram of fluorine produced (J) labor costs (4) costs to maintain and rebuild cells and (5) amortization of fixed capital. Fluorine production is highly capital intense. In addition, purification, compression, packaging, and distribution in cylinders increase the cost significantly. 

R. J. Ring and D. Royston, d Repiew of Fluorine Cells and Fluorine Production Facilities, Austrahan Atomic Energy Commission, AAEC/E 281 /, Sept. 1973. 

The balance of hydrogen fluoride is used ia appHcations such as stainless steel pickling inorganic fluoride production, alkylation (qv), uranium enrichment, and fluorine production. Hydrogen fluoride is used to convert uranium oxide to UF which then reacts with elemental fluorine to produce volatile UF. ... 

Fluorine. Fluorine is the most reactive product of all electrochemical processes (63). It was first prepared in 1886, but important quantities of fluorine were not produced until the early 1940s. Fluorine was required for the production of uranium hexafluoride [7783-81 -5] UF, necessary for the enrichment of U (see DIFFUSION SEPARATION METHODS). The Manhattan Project in the United States and the Tube Alloy project in England contained parallel developments of electrolytic cells for fluorine production (63). The principal use of fluorine continues to be the production of UF from UF. ... 

Fluorine has been compressed, Hquified, and shipped. However, most fluorine is produced and used on site. Fluorine production in the United States is based on electrolytic cells developed in the 1940s. Modem type "E" cells are rated for 6 kA (64). 

Fluorination of trimethylamine over cobalt trifluoride gives six fluorinated products [20] (equation 18). 

Reactions of alcohols with sulfur tetrafluoride, because of decomposition and/or polymerization, usually do not give fluorinated products However, in the presence of a hydrogen fluoride scavenger like triethylamine or pyridine, even such sensitive substrates as benzylic alcohols [555], 2-phenylethanol, and 2-furylmethanol [554] can be fluorinated to give the expected fluoro derivatives (equation 73)... 

A large range of man-made polymeric materials is available, from polyethylene, which is attacked by most organic chemicals, to fluorinated products such as polytetrafluoro-ethylene and polyethyletherketones, which have exceptional resistance to virtually all chemicals. All polymers have their own adhesive, welding and fabrication limitations which must be taken into account in the design of the coated item. These materials can also be used in solid form. 

Ni Production of Chlorination Fluorination Production of Processes where Production... 

The interaction between metal oxides and ammonium hydrofluoride at 100-250°C yields complex fluorometalates of ammonium and water. The water formed evaporates from the mixture, but can also lead to hydrolysis of the fluorination product in the process. In the very common form the fluorination of metal oxides by ammonium hydrofluoride can be described as follows ... 

Becker and Israel (1979) have studied the influence of the solvent in more detail. They determined the constant KD of the equilibrium between free ions and ion pairs (Schemes 10-12 and 10-13) conductometrically in five solvents (H20, MeCN, MeOH, EtOH, and Me2CO). An inverse linear relationship was found between the ratio of products [ArOS]/[ArF] (where ArOS is the product of heterolytic solvolysis) and Kd/e (e = dielectric constant). This result indicates that solvolysis products are formed mainly from free diazonium ions, whereas fluoro-de-diazoniation takes place in the ion pair. Of the solvents used, acetone gives the lowest value of KD, and thus the yield of the fluorinated product is highest in this solvent. 

Composition and Melting Points of Fluorination Products op the Reaction of Fluorine with Sn(CHa) ... 

Fluorinated Products Obtained by Treatment with DAST with Migration, or Retention of Configuration... 

Fluorinated Products Obtained" by Treatment with DAST with Normal Displacement... 

Displacement of the 3-hydroxyl group of 74 was carried out with Et2NSF3 (DAST) (DAST - diethylaminosulfur trifluoride) in dichloromethane. The expected fluorinated product 75 on treatment with aqueous perchloric acid led to regioselective epoxide ring opening to give 76, which on treatment with hydrazine hydrate at 100 °C for 18 h yielded 3,4-dihydroxy-8-oxo-octahydropyridazino[l,6-r/][l,2,4]triazine-l-carboxylic acid phenylamide 77 (Scheme 3) <1997T9357>. 

The reactivity of dipyrrolylmethane 236 has similarly been exploited in its reaction with 4-dimethylamino-l,l,l-trifluoro-3-buten-2-one 239 and trifluoromethanesulfonic anhydride to generate the iminium ion 240 followed by hydrolysis to give the fluorinated product 241 in 56% yield (Scheme 16) <2003CHE776>. 

Micelle formation in standard organic solvents such as toluene or THF is very useful, since fluorinated polymers are usually not soluble in standard solvents micelle formation therefore enables processing of fluorinated products with classical technologies, e.g., for coating applications. 

Fluorine was isolated by Henri Moissan at the end of June 1886 during an electrolysis of liquefied anhydrous hydrogen fluoride, containing potassium fluoride, at -23°C. The gas, produced at the anode, was fluorine. This achievement earned Moissan the 1906 Nobel prize in chemistry. Thousands of tons of fluorine are being produced today by essentially the same, albeit slightly improved, electrolytic method. Obviously, this scale of fluorine production means that fluorine chemistry has turned into an important branch of industry. This development can be understood if we look at fluorine from a chemist s point of view. 

In the development of the discussed fluorinated products a lot of fundamental insight has been gained into permeation and adhesion properties of surface-fluorinated polymers. Although this insight is not discussed in this paper, it may be of interest to mention a few significant fundamental discoveries and also to suggest directions for future development. 

Fluorine derivatives. See Morphactins Fluorine ores, 77 854-855 Fluorine perchlorate, 18 279 Fluorine production, 9 635... 

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