Patents by Inventor Gerd Leston

Gerd Leston 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: 4499312
    Abstract: A process is disclosed for separating 3,5-xylenol or 3,4-xylenol from other closely boiling polymethylated phenolics by treating a mixture of the phenolics with a metal halide salt. The metal halide salt preferentially forms a complex with the xylenol over other related phenolics in the mixture. The preferentially-formed complex of the xylenol may then be isolated from the mixture and the complex decomposed to provide a product substantially enriched in, or substantially entirely composed of the xylenol.
    Type: Grant
    Filed: February 21, 1984
    Date of Patent: February 12, 1985
    Assignee: Koppers Company, Inc.
    Inventor: Gerd Leston
  • Patent number: 4496774
    Abstract: A process is disclosed for separating nitrated phenolic compounds from other nitrated and unnitrated phenolics by treating a mixture of the phenolics with a metal halide salt. The metal halide salt preferentially forms a complex with one of the phenolics over other related phenolics in the mixture. The preferentially-formed complex of one of the phenolics may then be isolated from the mixture and the complex decomposed to provide a product substantially enriched in, or substantially entirely composed of, one phenolic. The process is particularly suitable for resolving a mixture comprising phenol or cresol from their ortho-nitrated derivatives, or a mixture of two isomeric nitrated phenols or cresols or a mixture of mono- and dinitrated phenols or cresols.
    Type: Grant
    Filed: July 23, 1984
    Date of Patent: January 29, 1985
    Assignee: Koppers Company, Inc.
    Inventor: Gerd Leston
  • Patent number: 4480140
    Abstract: Phenols alkylated in the ortho and/or para positions are produced in good yields and in the absence of isomers from phenolic compounds having at least two alkylateable ortho-ortho or ortho-para positions open. The phenolic compound is first partially chlorinated or brominated and the desired halogenated phenol having at least one open position ortho or para is reacted with an aldehyde having one to four carbon atoms and a secondary non-aromatic amine. The reaction is conducted in the liquid phase with a stoichiometric amount of the phenolic compound and stoichiometric or excess of stoichiometric amounts of the aldehyde and the amine. The reaction is performed at a temperature of from about 0.degree. C. to about 100.degree. C. to produce an aminoalkylated halogenated phenolic compound. This aminoalkylated halogenated phenolic compound is contacted with hydrogen in the presence of a metal catalyst at a temperature of about 100.degree. C. to about 175.degree. C.
    Type: Grant
    Filed: March 16, 1983
    Date of Patent: October 30, 1984
    Assignee: Koppers Company, Inc.
    Inventor: Gerd Leston
  • Patent number: 4479019
    Abstract: A process is disclosed for separating nitrated phenolic compounds from other nitrated and unnitrated phenolics by treating a mixture of the phenolics with a metal halide salt. The metal halide salt preferentially forms a complex with one of the phenolics over other related phenolics in the mixture. The preferentially-formed complex of one of the phenolics may then be isolated from the mixture and the complex decomposed to provide a product substantially enriched in, or substantially entirely composed of, one phenolic. The process is particularly suitable for resolving a mixture comprising phenol or cresol from their ortho-nitrated derivatives, or a mixture of two isomeric nitrated phenols or cresols or a mixture of mono-and dinitrated phenols or cresols.
    Type: Grant
    Filed: February 21, 1984
    Date of Patent: October 23, 1984
    Assignee: Koppers Company, Inc.
    Inventor: Gerd Leston
  • Patent number: 4475001
    Abstract: Ortho- or para-monoalkylated phenols or 2,4- or 2,6-dialkylphenols can be produced from phenolic compounds in good yields and in the absence of isomers. The starting phenol which has at least two available ortho or para positions unsubstituted is converted to a t-alkylated phenol having at least one ortho or para position unsubstituted. The desired t-alkylated phenolic compound is reacted with an aldehyde having one to four carbon atoms and a secondary aliphatic or alicyclic amine. The reaction is conducted in the liquid phase with a stoichiometric amount of the phenolic compound and stoichiometric or excess of stoichiometric amounts of the aldehyde and the secondary amine. The reaction is conducted at a temperature in the range of about 0.degree. C., to about 100.degree. C. and the reaction produces an aminoalkylated t-alkylated phenol. The aminoalkylated phenol is contacted with hydrogen in the presence of a metal catalyst at a temperature of about 100.degree. C. to about 175.degree. C.
    Type: Grant
    Filed: March 17, 1983
    Date of Patent: October 2, 1984
    Assignee: Koppers Company, Inc.
    Inventor: Gerd Leston
  • Patent number: 4469901
    Abstract: A process is disclosed for separating 5-isopropyl-m-cresol from other isopropylated m-cresols by treating a mixture of the isopropylated m-cresols with a metal halide salt. The metal halide salt preferentially forms a complex with 5-isopropyl-m-cresol over other related closely-boiling isopropylated m-cresols in the mixture. The preferentially-formed complex of 5-isopropyl-m-cresol may then be isolated from the mixture and the complex decomposed to provide a product substantially enriched in, or substantially entirely composed of, 5-isopropyl-m-cresol. The process is particularly suitable for isolating 5-isopropyl-m-cresol from closely-boiling isomers, and di-isopropylated m-cresols.
    Type: Grant
    Filed: January 3, 1984
    Date of Patent: September 4, 1984
    Assignee: Koppers Company, Inc.
    Inventor: Gerd Leston
  • Patent number: 4469900
    Abstract: A process is disclosed for separating closely-boiling chlorinated phenolic compounds from other chlorinated and unchlorinated phenolics by treating a mixture of the phenolics with a metal halide salt. The metal halide salt preferentially forms a complex with one of the phenolics over other related closely-boiling phenolics in the mixture. The preferentially-formed complex of one of the phenolics may then be isolated from the mixture and the complex decomposed to provide a product substantially enriched in, or substantially entirely composed of, one phenolic. The process is particularly suitable for resolving a mixture comprising phenol or cresol from their closely-boiling ortho-chlorinated derivatives, or a mixture of two isomeric chlorinated phenols or cresols or a mixture of closely-boiling mono- and dichlorinated phenols or cresols.
    Type: Grant
    Filed: January 4, 1984
    Date of Patent: September 4, 1984
    Assignee: Koppers Company, Inc.
    Inventor: Gerd Leston
  • Patent number: 4447658
    Abstract: A process is disclosed for separating 3,5-xylenol or 3,4-xylenol from other closely boiling polymethylated phenolics by treating a mixture of the phenolics with a metal halide salt. The metal halide salt preferentially forms a complex with the xylenol over other related phenolics in the mixture. The preferentially-formed complex of the xylenol may then be isolated from the mixture and the complex decomposed to provide a product substantially enriched in, or substantially entirely composed of the xylenol.
    Type: Grant
    Filed: September 30, 1982
    Date of Patent: May 8, 1984
    Assignee: Koppers Company, Inc.
    Inventor: Gerd Leston
  • Patent number: 4447654
    Abstract: A process is disclosed for separating nitrated phenolic compounds from other nitrated and unnitrated phenolics by treating a mixture of the phenolics with a metal halide salt. The metal halide salt preferentially forms a complex with one of the phenolics over other related phenolics in the mixture. The preferentially-formed complex of one of the phenolics may then be isolated from the mixture and the complex decomposed to provide a product substantially enriched in, or substantially entirely composed of, one phenolic. The process is particularly suitable for resolving a mixture comprising phenol or cresol from their ortho-nitrated derivatives, or a mixture of two isomeric nitrated phenols or cresols or a mixture of mono-and dinitrated phenols or cresols.
    Type: Grant
    Filed: September 30, 1982
    Date of Patent: May 8, 1984
    Assignee: Koppers Company, Inc.
    Inventor: Gerd Leston
  • Patent number: 4431846
    Abstract: A process is disclosed for reducing the concentration of o-ethylphenol in m,p-cresol by partially t-butylating a mixture of the above and equilibrating the resultant mixture to convert o-ethylphenol and its 6-t-butyl derivative to the thermodynamically most stable 4-t-butyl-o-ethylphenol. The resultant mixture may then be separated by fractional distillation to isolate m,p-cresol low in o-ethylphenol, optionally, the mono-t-butylated derivatives of m,p-cresol and leave behind the 4-t-butyl-o-ethylphenol, along with di-t-butylated derivatives of all the phenols.
    Type: Grant
    Filed: May 24, 1982
    Date of Patent: February 14, 1984
    Assignee: Koppers Company, Inc.
    Inventor: Gerd Leston
  • Patent number: 4429169
    Abstract: A process is disclosed for separating 5-isopropyl-m-cresol from other isopropylated m-cresols by treating a mixture of the isopropylated m-cresols with a metal halide salt. The metal halide salt preferentially forms a complex with 5-isopropyl-m-cresol over other related closely-boiling isopropylated m-cresols in the mixture. The preferentially-formed complex of 5-isopropyl-m-cresol may then be isolated from the mixture and the complex decomposed to provide a product substantially enriched in, or substantially entirely composed of, 5-isopropyl-m-cresol. The process is particularly suitable for isolating 5-isopropyl-m-cresol from closely-boiling isomers, and diisopropylated m-cresols.
    Type: Grant
    Filed: April 26, 1982
    Date of Patent: January 31, 1984
    Assignee: Koppers Company, Inc.
    Inventor: Gerd Leston
  • Patent number: 4429168
    Abstract: A process is disclosed for separating closely-boiling chlorinated phenolic compounds from other chlorinated and unchlorinated phenolics by treating a mixture of the phenolics with a metal halide salt. The metal halide salt preferentially forms a complex with one of the phenolics over other related closely-boiling phenolics in the mixture. The preferentially-formed complex of one of the phenolics may then be isolated from the mixture and the complex decomposed to provide a product substantially enriched in, or substantially entirely composed of, one phenolic. The process is particularly suitable for resolving a mixture comprising phenol or cresol from their closely-boiling ortho-chlorinated derivatives, or a mixture of two isomeric chlorinated phenols or cresols or a mixture of closely-boiling mono- and dichlorinated phenols or cresols.
    Type: Grant
    Filed: April 26, 1982
    Date of Patent: January 31, 1984
    Assignee: Koppers Company, Inc.
    Inventor: Gerd Leston
  • Patent number: 4424381
    Abstract: A process is disclosed for separating closely-boiling dihydric phenol compounds by treating a mixture of dihydric phenols with a metal halide salt. The metal halide salt preferentially forms a complex with one of the dihydric phenols over other related dihydric phenols in the mixture. The preferentially-formed complex of one of the dihydric phenols may then be isolated from the mixture and the complex decomposed to provide a product substantially enriched in, or substantially entirely composed of, one dihydric phenol. The process is particularly suitable for resolving a mixture comprising hydroquinone and catechol, or a mixture of hydroquinone and resorcinol, or a mixture of homocatechol and hydroquinone, or a mixture of catechol and resorcinol.
    Type: Grant
    Filed: April 26, 1982
    Date of Patent: January 3, 1984
    Assignee: Koppers Company, Inc.
    Inventor: Gerd Leston
  • Patent number: 4423253
    Abstract: A process is disclosed for separating t-butylated phenolic compounds from other t-butylated and unbutylated phenolics by treating a mixture of the phenolics with a metal halide salt. The metal halide salt preferentially forms a complex with one of the phenolics over other related phenolics in the mixture. The preferentially-formed complex of one of the phenolics may then be isolated from the mixture and the complex decomposed to provide a product substantially enriched in, or substantially entirely composed of, one phenolic. The process is particularly suitable for resolving a mixture comprising phenol or cresol from their ortho-t-butylated derivatives, or a mixture of two isomeric t-butylated phenols or cresols or a mixture of mono- and di-t-butylated phenols or cresols.
    Type: Grant
    Filed: April 26, 1982
    Date of Patent: December 27, 1983
    Assignee: Koppers Company, Inc.
    Inventor: Gerd Leston
  • Patent number: 4394526
    Abstract: Para-cresol is separated from a mixture comprising meta-cresol and various other methylated and ethylated phenols by preferentially complexing the para-cresol with one or more anhydrous or dehydrated inorganic salts selected from the group consisting of calcium bromide, lithium bromide, manganese bromide and magnesium chloride. The anhydrous inorganic salt is added to the phenolic mixture in an amount to give a mole ratio of salt to para-cresol in the mixture in the range of about 0.5 mole to one to about 1.5 mole to one. The para-cresol and salt form a complex and the complex is removed from the mixture of methylated and ethylated phenols. Then the complex is decomposed to recover the para-cresol and salt; the recovered salt may be recycled to complex with more para-cresol.
    Type: Grant
    Filed: September 26, 1980
    Date of Patent: July 19, 1983
    Assignee: Koppers Company, Inc.
    Inventor: Gerd Leston
  • Patent number: 4267389
    Abstract: Para-cresol is separated from a mixture comprising meta-cresol and various other methylated and ethylated phenols by preferentially complexing the para-cresol with one or more anhydrous or dehydrated inorganic salts selected from the group consisting of calcium bromide, lithium bromide, manganese bromide and magnesium chloride. The anhydrous inorganic salt is added to the phenolic mixture in an amount to give a mole ratio of salt to para-cresol in the mixture in the range of about 0.5 mole to one to about 1.5 mole to one. The para-cresol and salt form a complex and the complex is removed from the mixture of methylated and ethylated phenols. Then the complex is decomposed to recover the para-cresol and salt; the recovered salt may be recycled to complex with more para-cresol.
    Type: Grant
    Filed: June 29, 1979
    Date of Patent: May 12, 1981
    Assignee: Koppers Company, Inc.
    Inventor: Gerd Leston
  • Patent number: 4267390
    Abstract: A process is disclosed for the stepwise separation of para-cresol and meta-cresol from a mixture of methylated and ethylated phenols. The para-cresol forms a complex with a dehydrated or anhydrous inorganic halide salt selected from the group consisting of calcium bromide, lithium bromide, manganese bromide and magnesium chloride. The meta-cresol isomer is separated from the mixture by formation of a complex with sodium acetate. Where the anhydrous or dehydrated inorganic halide salt is added firstly to the mixture of methylated and ethylated phenols including para-cresol and meta-cresol, the halide salt is provided in an amount to give a mole ratio of the halide salt to para-cresol in the mixture in the range of about 0.5 to one to about 1.5 to one. The para-cresol complexes with the halide salt and the complex is then removed from the mixture. The para-cresol-salt complex is thereafter decomposed to recover the para-cresol.
    Type: Grant
    Filed: June 29, 1979
    Date of Patent: May 12, 1981
    Assignee: Koppers Company, Inc.
    Inventor: Gerd Leston
  • Patent number: 4267392
    Abstract: Para-cresol and meta-cresol are separated from a mixture of methylated and ethylated phenols by a two-stage process wherein the para-cresol is preferentially complexed with one or more anhydrous or dehydrated inorganic salts selected from calcium bromide, lithium bromide, manganese bromide and magnesium chloride. Then the meta-cresol is successively preferentially complexed with calcium bromide from the mixture of methylated and ethylated phenols from which the para-cresol complex has been removed. The anhydrous or dehydrated inorganic salt is added to the mixture of methylated and ethylated phenols including para-cresol and meta-cresol in an amount to give a mole ratio of the salt to para-cresol in the mixture in the range of about 0.5 to one to about 1.5 to one. The para-cresol-salt complex is removed from the mixture of methylated and ethylated phenols and then decomposed to recover the para-cresol.
    Type: Grant
    Filed: June 29, 1979
    Date of Patent: May 12, 1981
    Assignee: Koppers Company, Inc.
    Inventor: Gerd Leston
  • Patent number: 4267391
    Abstract: A process is disclosed for the stepwise separation of para-cresol and meta-cresol from a mixture of methylated and ethylated phenols. The para-cresol preferentially forms a complex with a dehydrated or anhydrous inorganic salt selected from the group consisting of calcium bromide, lithium bromide, manganese bromide and magnesium chloride. The meta-cresol isomer is separated from the mixture by formation of a complex with urea. Where the anhydrous or dehydrated inorganic salt is added firstly to the mixture of methylated and ethylated phenols including para-cresol and meta-cresol, the salt is provided in an amount to give a mole ratio of the salt to para-cresol in the mixture in the range of about 0.5 to one to about 1.5 to one. The para-cresol complexes with the salt and the complex is then removed from the mixture. The para-cresol-salt complex is thereafter decomposed to recover the para-cresol.
    Type: Grant
    Filed: June 29, 1979
    Date of Patent: May 12, 1981
    Assignee: Koppers Company, Inc.
    Inventor: Gerd Leston
  • Patent number: 4158101
    Abstract: Phenolic compounds are methylated with methane in the presence of a metallic catalyst selected from nickel or cobalt or mixtures thereof at a temperature in the range of about 300.degree. C. to around 475.degree. C.
    Type: Grant
    Filed: April 15, 1977
    Date of Patent: June 12, 1979
    Assignee: Koppers Company, Inc.
    Inventor: Gerd Leston