- Copper-Induced Telomerization of Tetrafluoroethylene with Fluoroalkyl Iodides
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In the presence of catalytic amounts of copper, telomerization of tetrafluoroethylene with fluoroalkyl iodides can be carried out at 80-100 deg C.As compared with usual high-temperature (200 deg C) telomerization process, the reaction time required is much shorter.
- Chen, Qing-Yun,Su, De-Bao,Yang, Zhen-Yu,Zhu, Rong-Xian
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- CURRENT BALANCE OF THE ELECTROCHEMICAL FLUORINATION OF A TRIALKYLAMINE
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The electrochemical fluorination of dibutylmethylamine was studied.All the fluorination products formed, liquid, gaseous, and dissolved in HF, and also the hydrogen evolved were quantitatively determined.From either their formulae or their relative fluorine contents the amount of current necessary for their formation was estimated.Altogether, the fluorination products determined cover about 86-97 percent of the current applied.A major part of the current was consumed by production of polyfluorinated products, which remained dissolved in the hydrogen fluoride.
- Dimitrov, A.,Stewig, H.,Ruediger, St.,Kolditz, L.
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- Fluorine chemistry - Wittig based synthesis of volatile organofluorine compounds
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A simple and practical method has been developed for the synthesis and characterization of several interesting classes of volatile organofluorine compounds from fluorophosphonium salts via their in situ generated corresponding ylides. The fluorinated phosphonium ylides react with hexafluoroacetone in DMF to generate perfluoroisobutylene, whereas in the presence of bromine or iodine containing electrophiles, tetrafluoroethylene, perfluoro-2-butene, perfluorocyclobutane, and 1H-heptafluoropropane are obtained.
- Bhadury, Pinaki S.,Singh, Sapna,Sharma, Mamta,Palit, Meehir,Jaiswal, Devendra K.
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- METHOD FOR PRODUCING TETRAFLUOROETHYLENE AND/OR HEXAFLUOROPROPYLENE
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PROBLEM TO BE SOLVED: To provide a novel method for producing tetrafluoroethylene and/or hexafluoropropylene. SOLUTION: The method for producing tetrafluoroethylene and/or hexafluoropropylene comprises thermally decomposing a perfluoroalkane represented by the general formula (1) defined by CnF2n+2, where n represents an integer of 4-28.] COPYRIGHT: (C)2016,JPOandINPIT
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Paragraph 0053-0054; 0058
(2016/11/09)
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- Depolymerization of Fluoropolymers
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A process for depolymerizing fluoropolymers includes continuously feeding a solid fluoropolymer, in particulate form, into a horizontal cylindrical first reaction zone. The fluoropolymer particles enter the first reaction zone at one end. Within the first reaction zone, a central axle from which protrudes at least one paddle, continuously rotates. The rotating paddle serves to advance the fluoropolymer particles along the reaction zone while agitating them. As the fluoropolymer particles pass along the reaction zone, they are subjected to an elevated temperature, thereby depolymerizing the fluoropolymer into a fluoro-containing compound-rich gas phase. A residual solids phase is withdrawn at the other end of the first reaction zone, as is the gas phase. Optionally, the gas phase is passed through a second reaction zone which is also at an elevated temperature. The gas phase is quenched, thereby to recover the fluoro-containing compounds as gaseous products.
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Page/Page column 4-5
(2009/06/27)
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- PRODUCTION PROCESSES FOR MAKING 1,1,1,2,2,3-HEXAFLUOROPROPANE
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A process for making HFC-236cb is disclosed. The process comprises reacting TFE with HFC-32 in the presence of at least one co-product and a suitable catalyst to produce a product mixture comprising HFC-236cb, wherein the total amount of the at least one co-product is at least 10 ppmv based on the total amount of the tetrafluoroethylene, the difluoromethane and the at least one co-product.
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Page/Page column 12-13
(2008/06/13)
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- Adsorbent for purifying perfluorocarbon, process for producing same, high purity octafluoropropane and octafluorocyclobutane, and use thereof
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To provide a purification adsorbent capable of effectively removing impurities contained in a perfluorocarbon and obtaining a perfluorocarbon reduced in the impurity content to 1 ppm by mass or less; a process for producing the adsorbent; high-purity octafluoropropane or octafluorocyclobutane; processes for purifying and for producing the octafluoropropane or octafluorocyclobutane; and uses thereof. Purification is performed using a purification adsorbent produced by a method comprising (1) washing an original coal with an acid and then with water, (2) deoxidizing and/or dehydrating the original coal, (3) re-carbonizing the original coal at a temperature of from 500 to 700° C. and (4) activating the original coal at a temperature of from 700 to 900° C. in a mixed gas stream containing an inert gas, carbon dioxide and water vapor.
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Page/Page column 17-18
(2008/06/13)
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- Noncatalytic manufacture of 1,1,3,3,3-pentafluoropropene from 1,1,1,3,3,3-hexafluoropropane
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1,1,3,3,3-Pentafluoropropene (CF3CH═CF2, HFC-1225zc) can be produced by pyrolyzing 1,1,1,3,3,3-hexafluoropropane (CF3CH2CF3, HFC-236fa) in the absence of dehydrofluorination catalyst at temperatures of from about 700° C. to about 1000° C. and total pressures of about atmosphere pressure in an empty, tubular reactor, the interior surfaces of which comprise materials of construction resistant to hydrogen fluoride.
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Page/Page column 3
(2008/06/13)
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- Method and apparatus for transforming chemical fluids using halogen or oxygen in a photo-treatment process
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A method of treatment of reactant fluids such as hydrochlorofluorocarbons (HCFCs), hydrofluorocarbons (HFCs), hydrochlorocarbons (HCCs), and hydrocarbons (HCs) for the production of new chemical fluids. Another method of treatment for the transformation of the reactant fluids having impurities present in the chlorofluorocarbons (CFCs) or fluorocarbons (FCs) for yielding a high quality chemical product. Reactant fluids with impurities present in used CFC or FC may form an azeotropic mixture. A photochemical reaction is used wherein the reactant fluids are molecules with hydrogen atoms in a hydrogen-carbon bond. The process is comprised of the following steps: placing the reactant fluids into a process compartment of the photochemical reactor; placing halogen fluid or oxygen fluid into the process compartment of the photochemical reactor, wherein the halogen fluid is selected from a group consisting of chlorine (Cl2), bromine (Br2) and iodine (I2); and irradiating the fluids and the halogen or oxygen fluid using radiant energy from lamps operating in the visible and ultraviolet light regions of the electromagnetic spectrum to conduct thermolysis, photolysis and photochemical treatment by halogenating or oxidizing the molecules of the reactant fluids with the halogen or oxygen fluids to form halogenated or oxidized fluids during a dwell time period.
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Page/Page column 6
(2008/06/13)
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- PYROLYSIS PROCESS
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The present invention relates to the pyrolysis of hydrochlorofluorocarbons to form fluoromonomers such as tetrafluoroethylene, the pyrolysis being carried out in a reaction zone lined with nickel and mechanically supported by a jacket of other corrosion resistant metal, the nickel lining providing an improved yield of valuable reaction products.
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Page/Page column 4-5
(2008/06/13)
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- METHOD OF A SIMULTANEOUS PREPARATION OF HEXAFLUOROPROPYLENE AND OCTAFLUOROCYCLOBUTANE
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A method of simultaneous and selective perpararation of hexafluoropropylene and octafluorocyclebutane comprising the steps of: (a) thermally decomposing difluorochloromethane to obtain tetrafluoroethylene and then supplying the resulting tetrafluoroethylene into a bed reactor equipped with a distributor for supplying steam; and (b) supplying steam into a flow of tetrafluoroethylene supplied into the fluidized bed reactor, through a distributor for supplying steam at a certain molar ratio of tetrafluoroethylene/stream, and then performing dimerization of tetrafluoroethylene in the fluidized bed reactor under an atmospheric pressure.
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- PROCESS FOR PRODUCING FLUOROMONOMER
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Processes for producing a fluoromonomer from a fluoropolymer, among which one that can be carried out more simply is a process wherein thermal decomposition of a fluoropolymer is preformed by means of a rotary kiln (5) so as to produce a fluoromonomer, the process comprising feeding a fluoropolymer and steam (3) into a rotary kiln and heating the fluoropolymer.
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- Carbon-chain isomerization during the electrochemical fluorination in anhydrous hydrogen fluoride - A mechanistic study
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The compounds i-C4H9SO2F, i-C3H7SO2F and cyclo-C3 H7C(O)F have been subjected to electrochemical fluorination in anhydrous hydrogen fluoride. The resulting products were fully analyzed by NMR spectroscopy. From the reaction balances, literature data and quantum chemical calculations, a new mechanism for carbon-chain isomerization during the electrochemical fluorination (ECF) is proposed. The key step in the formation of isomeric products is believed to be a ring closure reaction involving carbo-cationic or biradical intermediates.
- Ignat'ev, Nikolai V.,Welz-Biermann, Urs,Heider, Udo,Kucheryna, Andriy,von Ahsen, Stefan,Habel, Wolfgang,Sartori, Peter,Willner, Helge
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- Aerosol formulations of albuterol and 1,1,1,2-tetrafluoroethane
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Aerosol formulations substantially free of chlorofluorocarbons, for oral and/or nasal administration are described. The formulations comprise 1,1,1,2 tetrafluoroethane, a medicament, optionally an excipient and optionally a surfactant. Methods of treatment utilizing the formulations also are described.
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- Bimolecular kinetic studies with high-temperature gas-phase 19F NMR: Cycloaddition reactions of fluoroolefins
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A gas-phase NMR kinetic technique has been used for the first time to obtain accurate measurements of rate constants of some bimolecular, second-order cycloaddition reactions. As a test of the potential use of this technique for the study of second-order reactions, the rate constants and the activation parameters for the cyclodimerization reactions of chlorotrifluoroethylene (CTFE) and tetrafluoroethylene (TFE) were determined in the temperature range 240-340 °C, using a commercial high-temperature NMR probe. Obtaining excellent agreement of the results with published data, the technique was then applied to the reaction of 1,1-difluoroallene with 1,3-butadiene, the results of which indicate that the use of gas-phase NMR for reaction kinetics is particularly valuable when a reagent is available only in small amounts and in cases where there are several competing processes occurring simultaneously. The major processes observed in this reaction are regioselective [2+2] and [2+4] cycloadditions, whose rates and activation parameters were determined [k2=9.3×106 exp(-20.1 kcal mol-1/RT) L/mol-1 S-1 and k3=1.2×106 exp(- 18.4 kcal mol-1/RT) L/mol-1 S-1, respectively] in the temperature range 130-210 °C.
- Shtarov,Krusic,Smart,Dolbier Jr.
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p. 9956 - 9962
(2007/10/03)
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- Non-chlorofluorocarbon aerosol formulations
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Aerosol formulations substantially free of chlorofluorocarbons for oral and/or nasal administration are described. The formulations comprise 1,1,1,2,3,3,3-heptafluoropropane, a medicament, optionally an excipient and optionally a surfactant. Methods of treatment utilizing the formulations are also described.
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- INVESTIGATIONS IN THE REGION OF INDUSTRIAL FLUORINATED COMPOUNDS
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The synthesis and properties of ozone-friendly fluorohydrocarbons, fluoroolefins, and fluorinated compounds with functional groups (acids, alcohols, esters, and others), used for the creation of effective surfactants, ion-exchange membranes for various purposes, heat-resistant oils, and greases, were investigated.A technology was developed for the production of highly pure fluorinated compounds for microelectronics, fiber optics, and medicine.
- Maksimov, B. N.
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p. 1935 - 1940
(2007/10/03)
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- FLUORINATION OF POLYHALOGENATED UNSATURATED COMPOUNDS WITH VANADIUM PENTAFLUORIDE
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Vanadium pentafluoride reacts with polyfluorinated and polychlorinated olefins, alkadienes, cycloalkenes and cyclodienes in CFCl3 or without a solvent at -25 deg C to 100 deg C, forming products of addition of two fluorine atoms across the C=C bond.
- Bardin, V. V.,Avramenko, A. A.,Furin, G. G.,Krasilnikov, V. A.,Karelin, A. I.,et al.
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p. 385 - 400
(2007/10/02)
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- REACTION OF POLYFLUORINATED CYCLOALKANES WITH VANADIUM, ANTIMONY, AND NIOBIUM PENTAFLUORIDES
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Polyfluorinated cycloalkanes are fluorinated by vanadium pentafluoride at 25-60 deg C.Conjugation between the C=C bond of the cycloalkene and the aromatic ring facilitates the reaction, whereas the reactivity of the unconjugated olefin fragment is lower than or is equal to that of the aromatic ring.The antimony pentafluoride fluorinates polyhalogenocyclohexenes at 150 deg C, while niobium pentafluoride does not exhibit fluorinating characteristics under these conditions.
- Bardin, V. V.,Avramenko, A. A.,Petrov, V. A.,Krasil'nikov, V. A.,Karelin, A. I.,et al
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p. 536 - 540
(2007/10/02)
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- Cyclopropane Chemistry. Part 4. The Reactions of 1,2,2-Trifluoroethylidene with Alkenes and Pyrolysis of the Resulting Cyclopropanes
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1,2,2-Trifluoroethylidene, generated by the pyrolysis of (1,1,2,2-tetrafluoroethyl)trifluorosilane, reacts with tetrafluoroethylene, ethylene, and a series of methyl-substituted ethylenes to give the corresponding 1-fluoro-1-difluoromethylcyclopropanes in good yield; cyclohexene gives the corresponding norcarane, and tris(trifluoromethyl)phosphine gives the corresponding phosphorane (CF3)3P(+)-C(-)F-CHF2.Pyrolysis of 1,2,2,3,3-pentafluoro-1-difluoromethylcyclopropane affords difluorocarbene and 3H-pentafluoropropene, but pyrolysis of the methyl-substituted cyclopropanes results in the formation of dienes in high yield, e.g. the 1,4-dienes CHF=CF-CMeR-CMe=CH2 from the cyclopropanes (R = H or Me) or 1,3-dienes from the methyl-substituted cyclopropanes, e.g. --> CH2=CMe-C(CHF2)=CH2.In certain cases further dehydrofluorination of the 1,3-dienes affords trienes, e.g. --> CH2=CMe-C(=CHF)-CMe=CH2.
- Haszeldine, Robert N.,Rowland, Ronald,Speight, James G.,Tipping, Anthony E.
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p. 314 - 324
(2007/10/02)
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- CYCLOPROPANE CHEMISTRY. PART 5 . HEXAFLUOROCYCLOPROPANE AS A SOURCE OF DIFLUOROCARBENE
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Thermolysis of hexafluorocyclopropane in the presence of ethylene, propene, vinyl chloride, and vinyl bromide gives good yields of the corresponding 1,1-difluorocyclopropanes, formed by addition of difluorocarbene to the olefin.The tetrafluoroethylene formed dimerises to octafluorocyclobutane, co-dimerises with the olefin, or survives, depending on the reaction conditions.With allene, hexafluorocyclopropane gives 1-(difluoromethylene)cyclopropane, 2,2,3,3-tetrafluorospiropentane, and products derived from tetrafluoroethylene and allene.
- Birchall, J. Michael,Fields, Roy,Haszeldine, Robert N.,McLean, Reginald J.
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p. 487 - 496
(2007/10/02)
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