E.i. Dupont De Nemours and Company

Other

James L Webster

Leo E Manzer

Jan J Lerou

Elrey L McCann

Douglas W Bruhnke

Steven Henry Swearingen

William H Manogue

Swiatoslaw Trofimenko

Paul R Resnick

Marion G Waggoner

Cristobal Bonifaz

John Charles Gebhard, Jr

Scott Christopher Jackson

James Arthur Trainham

Tetrafluoroethylene and other valuable 2-carbon atom fluorocarbon is made by reacting fluorine-containing compound such metal fluoride with CO in an energized state, e.g. plasma excitation, to form a gaseous reaction mixture which is a precursor to COF.sub.2, followed by reacting this reaction mixture with carbon and quenching to obtain the desired fluorocarbon.

Process for the preparation of perfluorocarbons

Tetrafluoroethylene is obtained by subjecting metal fluoride, such as sodium fluoride, calcium fluoride or silicon fluoride, to a plasma to form a gaseous mixture of metal and reactive fluorine. This gaseous mixture is then reacted with a bed of carbon particles at a temperature at which the metal, when non-carbonaceous, does not condense. The resultant reaction mixture is then quenched to obtain the tetrafluoroethylene. Typically, the plasma will be at a temperature of at least 4500.degree. C. and the temperature of the carbon bed will be in the range of 2000.degree. C. to 3500.degree. C.

Preparation of tetrafluoroethylene

Carbonyl fluoride is produced by reacting fluorine-containing compound such as metal fluoride with CO in an excited state, such as produced by a plasma, to obtain a gaseous reaction mixture, which can then be quenched to obtain the COF.sub.2.

Manufacture of carbonyl floride

Metal fluoride and carbon are fed to a plasma flame to form a gaseous reaction mixture which is quenched to form tetrafluoroethylene. The plasma flame can be formed from a non-reactive gas and the metal fluoride and carbon then become part of the plasma flame when fed into it. Alternatively, one of the reactants can form the plasma flame and then the other reactant is fed into it.

Halocarbon is carbonized at a temperature of at least 600.degree. C. in the presence of excess hydrogen and the absence of water to obtain carbon and anhydrous haloacid as the primary reaction products.

Carbonization of halocarbons

A single step, vapor phase process for the chlorofluorination of methane forms trifluoromethane and/or tetrafluoromethane in high yield. A Cr.sub.2 O.sub.3 catalyst is preferred.

Preparation of fluorinated methanes

Halogen-containing organic compounds are reacted with alkali metal or earth alkaline metal carbonate and/or oxide to convert the halogen component of the compound to halide of the metal, thus converting a liquid or gaseous compound to a solid halogen-containing compound for use or safe landfill disposal.

Chemical disposal of halocarbons

The present invention relates to syntheses of perfluoropropane-- .e., octafluoropropane--from acyclic three-carbon hydrocarbons or partially or totally halogenated acyclic three-carbon hydrocarbons.

Synthesis of perfluoropropane

The present invention relates to multistep syntheses of hexafluoropropylene from hexachloropropylene. In all these syntheses the first step is a fluorination of the starting material; later steps convert the initial products to CF.sub.3 --CFCl--CF.sub.3, which is dehalogenated to the desired product.

Multistep synthesis of hexafluoropropylene

The present invention relates to multistep syntheses of hexafluoropropylene from acyclic three-carbon hydrocarbons or partially halogenated acyclic three-carbon hydrocarbons. In all these syntheses the first step is a vapor-phase chlorofluorination of the starting material to one or more saturated chlorofluorocarbons. Novel catalysts are also provided.

The present invention relates to multistep syntheses of hexafluoropropylene from propane, propylene or partially halogenated acyclic three-carbon hydrocarbons. In all these syntheses the first step is a vapor-phase chlorofluorination of the starting material to the unsaturated chlorofluorocarbon CF.sub.3 CClCCl.sub.2.

Spherical-shaped particles having an average diameter of 10 to 100 microns and the surface thereof is covered with hemispherical-shaped bumps about 0.1 micron in diameter, the particles being a copolymer of alpha-olefins and alpha, beta-ethylenically unsaturated carboxylic acid having 3 to 8 carbon atoms, the copolymer having up to 90% of the carboxylic acid groups ionized by neutralization with metal ions. The particles form a free-flowing powder useful in preparing clear, protective, shatter-resistant coatings for glass, and protective coatings for metals and other material.

Spherical-shaped particles from ionomer resins and ethylene/carboxylic

Method whereby spherical-shaped copolymer particles having a rough surface are produced. In a closed shear zone of a shear device under positive pressure water, at least 0.6% by weight of ammonia, and up to 50% by weight of copolymers of alpha-olefins and alpha, beta-ethylenically unsaturated carboxylic acids having from 3 to 8 carbon atoms, and optionally an additional monoethylenically unsaturated monomer, the copolymer having from 0% to 90% of the carboxylic acid groups ionized by neutralization with metal ions, are sheared at a temperature above the melting point but below the thermal degradation point of the copolymer to form a homogeneous aqueous slurry wherein the copolymer particles have an average particle size of less than 100 microns. The slurry is maintained with agitation at a temperature above the copolymer melting point for at least 0.5 minute until substantially all the copolymer particles become spherical. Agitation is continued and the slurry is cooled to a temperature below about the copolymer freezing point over a period of at least 0.3 minute while the pressure is maintained at sufficient level to keep the water in the liquid state. The pressure of the cooled slurry is reduced to atmospheric pressure and the copolymer particles are separated from the aqueous component of the slurry. The spherical-shaped particles have an average diameter of 10 to 100 microns and the surface thereof is covered with hemispherical shaped bumps about 0.1 micron in diameter. The particles form a free-flowing powder useful in preparing clear, protective, shatter-resistant coatings for glass, and protective coatings for metals and other materials.

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Parkersburg, WV, United States of America

James L Webster