Patents by Inventor Francis E. Evans

Francis E. Evans has filed for patents to protect the following inventions. This listing includes patent applications that are pending as well as patents that have already been granted by the United States Patent and Trademark Office (USPTO).

  • Patent number: 4943423
    Abstract: The present invention provides a process for recovering boron trifluoride from an impure gaseous boron trifluoride residue. The process comprises: (a) feeding an impure gaseous boron trifluoride residue containing sulfur dioxide as an impurity into a mixture of boric and sulfuric acids wherein the acid mixture absorbs boron trifluoride from the impure boron trifluoride residue and slightly absorbs or does not absorb sulfur dioxide from the impure gaseous boron trifluoride residue; and (b) removing the unabsorbed sulfur dioxide from the acid mixture.The present invention also provides a boron trifluoride preparation and purification process.
    Type: Grant
    Filed: November 29, 1988
    Date of Patent: July 24, 1990
    Assignee: Allied-Signal Inc.
    Inventors: Francis E. Evans, Kenneth H. Schroeder, William J. Wagner
  • Patent number: 4781909
    Abstract: Sulfuric acid contaminated with boron and fluoride values such as the waste acid of a boron trifluoride process is purified by contacting the contaminated acid with an inert gas to desorb boron trifluoride, and the inert gas is stripped by contacting with an absorbing liquid including concentrated sulfuric acid. Hydrogen fluoride and/or fluorosulfuric acid are added to contaminated sulfuric acid as agents to spring non-volatile boron value. In addition, the water content of the contaminated acid is adjusted within a narrow concentration range, to improve the efficiency of both the stripping and the absorption operations. The absorption of boron trifluoride into the absorbing sulfuric acid is improved when it contains boric acid. Preferably the contaminated sulfuric acid to be purified is one portion of the waste liquid and the absorbing liquid is another portion of the waste liquid of a boron trifluoride manufacturing process.
    Type: Grant
    Filed: May 19, 1986
    Date of Patent: November 1, 1988
    Assignee: Allied-Signal Inc.
    Inventors: Francis E. Evans, Joel P. Guptill
  • Patent number: 4371707
    Abstract: A process for the conversion of boron trifluoride dimethyl ether complex to boron trifluoride dialkyl ether complex substantially free of dimethyl ether impurities, which comprises reacting the boron trifluoride-dimethyl ether complex, in the liquid phase, in the presence of dialkyl ether wherein at least one of the alkyl groups contains at least two carbon atoms, in a restricted vapor equilibration region, while simultaneously sweeping the said vapor equilibration region with a substantially inert gas, and heating to distill off the dimethyl ether. High purity of the boron trifluoride dialkyl ether complex is attained with this method, with only minimal traces of the boron trifluoride dimethyl ether complex, dimethyl ether remaining. The preferred product is boron trifluoride diethyl ether.
    Type: Grant
    Filed: December 15, 1980
    Date of Patent: February 1, 1983
    Assignee: Allied Corporation
    Inventors: Richard E. Eibeck, Martin A. Robinson, Francis E. Evans, Eugene B. Recla
  • Patent number: 4265871
    Abstract: Sulfuric acid contaminated with boron and fluoride values such as the waste acid of a boron trifluoride process is purified by contacting the contaminated acid with an inert gas to desorb boron trifluoride, and the inert gas is stripped by contacting with an absorbing liquid including concentrated sulfuric acid. Fluosulfonic acid is added to contaminated sulfuric acid at levels approximately three times the molar values of boric acid contaminant as an agent to spring non-volatile boron values. The absorption of boron trifluoride into the absorbing sulfuric acid is improved when it contains boric acid. Preferably the contaminated sulfuric acid to be purified is one portion of the waste liquid and the absorbing liquid is another portion of the waste liquid of a boron trifluoride manufacturing process. Boric acid is added to the absorbing liquid, then boron trifluoride is stripped from the inert gas and absorbed into the absorbing liquid.
    Type: Grant
    Filed: May 7, 1979
    Date of Patent: May 5, 1981
    Assignee: Allied Chemical Corporation
    Inventors: Charles J. Felice, Jr., Francis E. Evans, Martin A. Robinson, Richard E. Eibeck
  • Patent number: 4227027
    Abstract: When saturated with boron trifluoride, certain polyhydric alcohols form adducts which catalyze hydrocarbon alkyl transfer reactions for which boron trifluoride is catalytic. The adduct is recovered from the reaction mixture and recycled, greatly reducing boron and fluoride values in the product and in any effluent. Examples include propylation of toluene in the presence of a recycled adduct of boron trifluoride with mannitol or sorbitol, and the oligomerization of decene by a recycled adduct of boron trifluoride with mannitol or butanediol. Some of the catalysts become viscous on cooling and are thus more easily separated from the reaction products which remain in a separate liquid phase.
    Type: Grant
    Filed: November 23, 1979
    Date of Patent: October 7, 1980
    Assignee: Allied Chemical Corporation
    Inventors: Robert E. Booth, Francis E. Evans, Richard E. Eibeck, Martin A. Robinson
  • Patent number: 4216168
    Abstract: High purity tetrahydrocarbylammonium tetrahydridoborates are prepared under anhydrous conditions by reacting tetrahydrocarbylammonium salts with at least 8% molar excess of an alkali metal hydroxide in the presence of ethanol to produce the corresponding tetrahydrocarbylammonium hydroxides and alkali metal salts, removing the alkali metal salts and adding an alkali metal borohydride to the solution to produce the corresponding tetrahydrocarbylammonium tetrahydridoborates and alkali metal hydroxides.
    Type: Grant
    Filed: October 16, 1978
    Date of Patent: August 5, 1980
    Assignee: Allied Chemical Corporation
    Inventors: Francis E. Evans, Charles J. Lind, Martin A. Robinson
  • Patent number: 4209654
    Abstract: When saturated with boron trifluoride, certain polyhydric alcohols form adducts which catalyze reactions for which boron trifluoride is catalytic. The adduct is recovered from the reaction mixture and recycled, greatly reducing boron and fluoride values in the product and in any effluent. Examples include propylation of toluene in the presence of a recycled adduct of boron trifluoride with mannitol or sorbitol.
    Type: Grant
    Filed: October 16, 1978
    Date of Patent: June 24, 1980
    Assignee: Allied Chemical Corporation
    Inventors: Robert E. Booth, Francis E. Evans, Richard E. Eibeck, Martin A. Robinson
  • Patent number: 4174349
    Abstract: Fluoroorganic compounds are prepared by reacting a haloorganic starting material in which at least one halo atom is replaceable with a fluorine atom by metathetical exchange, with calcium fluoride in the presence of a crown ether and an anhydrous, polar, basic organic solvent which complexes with the calcium ion and contains no --OH groups, at a temperature and for a period of time adequate to effect fluorination.
    Type: Grant
    Filed: October 30, 1978
    Date of Patent: November 13, 1979
    Assignee: Allied Chemical Corporation
    Inventors: Francis E. Evans, Morris B. Berenbaum, Richard E. Eibeck, Martin A. Robinson
  • Patent number: 4157377
    Abstract: Dry calcium fluoborate suitable for use in the manufacture of boron trifluoride is produced by reacting, in an aqueous medium, calcium fluoride, hydrofluoric acid and boric acid followed by removing water from the calcium fluoborate reaction product by purging the reaction product with a dry inert gas such as nitrogen, at a temperature between about 140.degree. to 160.degree. C.
    Type: Grant
    Filed: September 5, 1978
    Date of Patent: June 5, 1979
    Assignee: Allied Chemical Corporation
    Inventors: Francis E. Evans, Charles J. Lind, Richard E. Eibeck, Martin A. Robinson
  • Patent number: 4072027
    Abstract: A stabilized heat exchange medium is disclosed including a fluorocarbon, an absorbant and a tribasic phosphite stabilizer. The preferred absorbants are assymetrical furan derivatives containing at least 1 oxygen with a single bond to an adjacent carbon, and is most preferably an alkyl tetrahydrofurfuryl ether. The fluorocarbon contains 1 or 2 carbons, 1 or 2 hydrogens and the remainder chlorine and fluorine. The tribasic phosphites are of the formula (R.sub.1 'O)(R.sub.2 'O)(R.sub.3 'O)P, wherein R.sub.1 ', R.sub.2 ' and R.sub.3 ' are each independently alkyl, alkenyl, phenyl, alkylene phenyl, alkylene alkylphenyl or alkylphenyl.
    Type: Grant
    Filed: January 19, 1977
    Date of Patent: February 7, 1978
    Assignee: Allied Chemical Corporation
    Inventors: Morris B. Berenbaum, Francis E. Evans, Richard E. Eibeck, Martin A. Robinson
  • Patent number: 3956236
    Abstract: A composition for increasing flame resistance of a step-reaction polymer comprising a metal salt of certain organic acids in combination with certain organic acids or their ammonium salts, the method of treating the step-reaction polymer with the composition and the resulting treated polymer.
    Type: Grant
    Filed: April 29, 1974
    Date of Patent: May 11, 1976
    Assignee: Allied Chemical Corporation
    Inventors: Francis E. Evans, Kenneth B. Gilleo
  • Patent number: 3943100
    Abstract: A flame resistant organic polymer which decomposes into fragments containing acidic and/or basic groups and the process for making same comprising treating an organic polymer which decomposes into said fragments with from about 0.5 to about 25 weight percent of a compound which contains at least one functional radical selected from --0--, --S-- and --N-- and at least one carboxyl or mercapto group which is able to dissociate in water to provide a free positively charged ion.
    Type: Grant
    Filed: December 17, 1973
    Date of Patent: March 9, 1976
    Assignee: Allied Chemical Corporation
    Inventors: Morris B. Berenbaum, Kenneth B. Gilleo, Francis E. Evans