Fluorocarbons production

HF is used as a source of fluorine for production of all the various fluorocarbon products. HF reacts in the presence of a suitable catalyst and under the appropriate temperature and pressure conditions with various organic chemicals to yield a family of products. A by-product stream of hydrochloric acid may be co-produced. 

The introduction of the chlorofluorocarbon (CFC) fluids in the early 1930s marked the incepuon of the halofluorocarbon industry. Both in terms of tonnage produced and product value, the CFCs have dominated the organofluorocarbon industry and have provided the feedstocks for the development of other fluorocarbon products such as poly(tetrafluoroethylene). 

Aliphatic dissolution inhibitors, low molecular weight, 15 177 Aliphatic endoperoxides, 18 442, 443 Aliphatic fluorocarbon production Europe, 11 870-871 Pacific Rim/India, 11 871 United States, 11 869-870 Aliphatic fluorocarbons, surface energy of, 21 604... 

Aromatic copolyesters, 13 372 Aromatic diacyl peroxides, 14 283 Aromatic diisocyanates, urethanes obtained from, 25 462—463 Aromatic epoxies, 10 347-348 Aromatic ethers, 10 574 Aromatic fluorocarbon production, global, 11 871-872... 

Fluorocarbon groups, containing titanium complexes, 25 98 Fluorocarbon industry, 18 303 Fluorocarbon production, 11 869 Fluorocarbons... 

Pacific Rim/India, aliphatic fluorocarbon production in, 22 871 Pacific salmon... 

United States, See also American entries Army Corps of Engineers Atomic Energy Commission (AEC) Environmental Protection Agency (EPA) Federal entries Food and Drug Administration (FDA) Government entries National entries OSHA ozone exposure limits U.S. entries acrylic fiber consumption in, ll 220t acrylic fiber production in, 11 189 advanced materials research, 1 696 air separation industry in, 17 754 aliphatic fluorocarbon production in,... 

Freon is a commercial trademark for a series of fluorocarbon products used in refrigeration and air-conditioning equipment, as aerosol propellants, blowing agents, fire extinguishing agents, and cleaning fluids and solvents. Many types contain chlorine as well as fluorine, and should be called chlorofluorocarbons (CFCs) [85,86]. 

Fluorocarbon products and Portland cement were purchased from DuPont-Mitsui Fluorochemicals Co. and Chichibu-Onoda Cement Corp., respectively. The sheet type photocatalyst was prepared by the following procedures. Powders of Ti02, PTFE and AC were mechanically mixed with some solvents. The mixture was pressed into a sheet with a roller. The typical content of Ti02 and AC in the sheet was 30% and 10%, respectively. A 100 mm square portion of the sheet (0.5 mm thick) weighed ca. 5 g. 

Although reaction of [Pt(COD)2] alone with OFCOT did not produce any metal-fluorocarbon products, addition of two molar equivalents of PPh3, AsPh3, or t-BuNC to [Pt(COD)2] followed by addition of OFCOT yielded... 

Fig. 17. Relationship between the rate of increase in fluorocarbon production and the year at which the stratosphere will exceed 16 ppb of Cl,.

That the interaction of the radical cations with nucleophiles has the potential of providing a special derivative chemistry is indicated by the products of P attack found in this work. One specific diene is obtained in quantitative yield in each instance. The thermal degradation of the salts yields the same fluorocarbon products as the F" attack, indicating that the first step of the pyrolysis involves transfer from anion to cation. 

The F NMR spectra of the reaction products from the attack on C F AsFfi by show that the fluorocarbon products are C F and the 1,4-diene in a 1 1 molar ratio. These products are exactly the same as in the pyrolysis of the salt. The production of equimolar quantities of C Fg and the diene C Fg in both of these reactions is in harmony with rapid transfer of an electron from the addition product radical, C6p7, to another C F ion. ... 

Fluorocarbon products that do not contain chlorine and/or bromine (i.e., fully fluorinated and hydrofluorinated [HFC] products) are not stratospheric ozone-depleters, and production of these products is not being eliminated by the Montreal Protocol. They are, however, restricted by the U.S. Clean Air Act and must be recovered rather than released to the atmosphere. 

Freon [Du Pont], TM for a series of fluorocarbon products used in refrigeration and air-condi-... 

However, in the presence of K[HFj] (or binary Group 1 or Group 2 fluorides) in an autoclave at 250 C, the principal fluorocarbon product of the reaction between CIF 3 and COFj was bis(trifluoromethyl)peroxide, F3COOCF3 (92.3%), with only a small amount of by-product CF., (1.5%) being formed [587] ... 

When Molina and Rowland made their prediction in 1974, world production of CFCI3 and CF2CI2 was approximately 0.3 and 0.5 Mton respectively fluorocarbon production in the US was growing by 8.7% per year around 1970 [27]. Six years later, and every year since then, the predicted ozone hole was detected over Antarctica, when the chlorine concentration in the same atmospheric layer was approximately 2000 pmol mol [29]. After this dear evidence of the deleterious effects of CFC, in 1987 this class of substance and most bromofluorocarbons were banned from further industrial use in the Montreal Protocol (ratified by the first 29 states in 1989). Because of the decade-long lifetime of stratospheric CFC, their phasing-out can be expected to show an effect no earlier than approximately 2040. 

The controversy has not hurt business for the chlorine industry, which is booming.238 There have been some shifts in the product line. Methylene chloride demand is dropping. More trichloroethylene is being produced as a feedstock for fluorocarbon production. More sodium chlorite is being produced as a precursor for chlorine dioxide to be used in the bleaching paper. The trend should start downward in the future as chlorine-free alternatives are found and as ageing plants are retired. 

Calculated ozone depletion as a function of time for two cases of stopping fluorocarbon production at the end of 1976 and at the end of 1978 (Miller et al. 1978). (By courtesy of Atmospheric Emironmem)... 

Caffeine extraction Fluorocarbon production Paint removers Rubber... 

Fluorocarbons are known to introduce durable water and oil repellency (DWOR) and, as such, they are apphed in water- and stain-repellent fabrics for apparel. The combination of water and oil repellency is a typical behavior of fluorocarbon products. In the past, finishes based on C8 fluorocarbons (eight carbon atoms in the structure) were mainly used. However, concerns arose associated with these C8 fluorocarbons, more specifically with respect to PFOA (perfluorooctanoic acid or pentadecafluorooctanoic acid) and PFOS (perfluorooctane sulphonate or heptadecafluoro-l-octanesulfonic acid). 

The tendency is to replace the C8 fluorocarbon chemistry by C6 or C4 fluorocarbon products or even fluorine-free water repellents. Currently, new commercial DWOR finishes are coming onto the market based on short chain fluorocarbons (C6 or C4 fluorocarbon chemistry), hybrid systems, or they are fluorine free. 

Figure 15.3 is a schematic of the apparatus used in the Kel-Chlor process. A unit was constructed and operated in conjunction with a fluorocarbon production in the United States. The recovered chlorine was recycled to the precursor process. The plant is no longer in operation. It is reported that corrosion problems became severe. 

There are several other groups of insoluble mercury compounds. One plant that included a fluorocarbons unit adopted a different approach to mercury control [108]. The waste HCl from fluorocarbon production was shipped several hundred kilometers to a steel mill for use in pickle liquor. The trucks that carried the waste acid then returned empty. The solution adopted was to fill some of the returned trucks with waste pickle liquor, which is strong in FeCh- This was available at a very low cost and nearly zero incremental freight expense. Combining it with chloride-containing wastewater that had been made alkaline produced the reaction ... 

Saturated fluorocarbon production via cobalt trifluoride fluorination has featured in work on (i) a new synthesis of polyperfluorocyclobutene (2) (see Scheme 1), (ii) compounds derived from photo-isomerization of perfluoro-cyclohexene (see Scheme 2 and p. 55),(iii) polyfluoro-n-octanes and -n-hexadecanes (see Scheme 3), (iv) the fluorination of alkyladamantanes, °... 

Fluorocarbons are available for commercial and industrial use in various grades with essentially the same composition from one producer to another. Purities of most fluorocarbon products are a minimum of 99 volume percent. For special applications very high purity grades are available. 

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