Patents by Inventor An-I Yeh

An-I Yeh 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).

  • Separation of isopropyl ether from methyl ethyl ketone by extractive distillation
    Patent number: 4544454
    Abstract: Isopropyl ether cannot be completely removed from isopropyl ether - methyl ethyl ketone mixtures by distillation because of the presence of the minimum binary azeotrope. Isopropyl ether can be readily removed from mixtures containing it and methyl ethyl ketone by using extractive distillation in which the extractive distillation agent is a higher boiling oxygenated and/or nitrogenous organic compound or a mixture of these. Typical examples of effective agents are adiponitrile; ehtylene carbonate plus dimethylformamide; adiponitrile plus dimethylformamide plus glycerine.
    Type: Grant
    Filed: February 10, 1984
    Date of Patent: October 1, 1985
    Inventors: Lloyd Berg, An-I Yeh
  • Separation of methyl acetate from methanol by extractive distillation
    Patent number: 4543164
    Abstract: Methyl acetate cannot be completely removed from methyl acetate-methanol mixtures by distillation because of the presence of the minimum binary azeotrope. Methyl acetate can be readily removed from mixtures containing it and methanol by using extractive distillation in which the extractive distillation agent is a higher boiling oxygenated, nitrogenous and/or sulfur containing organic compound or a mixture of these. Typical examples of effective agents are dimethylsulfoxide; glycerine plus propylene glycol; ethylene glycol plus DMSO plus 1,5-pentanediol. Methanol can be removed as the overhead product from methyl acetate when the extractive distillation agent is nitrobenzene, propylene carbonate or ethylene glycol phenyl ether.
    Type: Grant
    Filed: April 14, 1983
    Date of Patent: September 24, 1985
    Inventors: Lloyd Berg, An-I Yeh
  • Separation of n-butyl acetate from n-butanol by extractive distillation
    Patent number: 4525245
    Abstract: n-Butyl acetate cannot be completely removed from n-butyl acetate - n-butanol - water mixtures by distillation because of the presence of the minimum ternary azeotrope. n-Butyl acetate can be readily removed from mixtures containing it, n-butanol and water by using extractive distillation in which the extractive distillation agent is a higher boiling oxygenated, nitrogenous and/or sulfur containing organic compound or a mixture of these. Typical examples of effective agents are dimethylsulfoxide; dimethylsulfoxide and 1,4-butanediol; dimethylsulfoxide, dimethylformamide and 1,6-hexanediol.
    Type: Grant
    Filed: May 7, 1984
    Date of Patent: June 25, 1985
    Inventors: Lloyd Berg, An-I Yeh
  • Separation of isopropyl ether from isopropanol and water by extractive distillation
    Patent number: 4510022
    Abstract: Isopropyl ether cannot be completely removed from isopropyl ether-isopropanol-water mixtures by distillation because of the presence of the minimum ternary azeotrope. Isopropyl ether can be readily removed from mixtures containing it, isopropanol and water by using extractive distillation in which the extractive distillation agent is a higher boiling oxygenated, nitrogenous and/or sulfur containing organic compound or a mixture of these. Typical examples of effective agents are ethylene glycol; dimethylsulfoxide plus propylene glycol; dimethylsulfoxide plus dimethylformamide plus diethylene glycol diethyl ether.
    Type: Grant
    Filed: August 8, 1983
    Date of Patent: April 9, 1985
    Inventors: Lloyd Berg, An-I Yeh
  • Separation of n-butyl acetate from n-butanol by extractive distillation
    Patent number: 4507176
    Abstract: n-Butyl acetate cannot be completely removed from n-butyl acetate-n-butanol--water mixtures by distillation because of the presence of the minimum ternary azeotrope. n-Butyl acetate can be readily removed from mixtures containing it, n-butanol and water by using extractive distillation in which the extractive distillation agent is a higher boiling oxygenated, nitrogenous and/or sulfur containing organic compound or a mixture of these. Typical examples of effective agents are N,N-dimethylacetamide, dimethylsulfoxide and acetamide, ethylene glycol propylene glycol, dimethylsulfoxide and acetamide.
    Type: Grant
    Filed: May 7, 1984
    Date of Patent: March 26, 1985
    Inventors: Lloyd Berg, An-I Yeh
  • Separation of methanol from acetone by extractive distillation
    Patent number: 4501645
    Abstract: Methanol cannot be completely removed from its mixture with acetone by distillation because of the presence of the minimum binary azeotrope. Methanol can be readily removed from mixtures containing it and acetone by using extractive distillation to bring off the methanol as overhead product in a rectification column by using extractive distillation in which the extractive distillation agent is an effective higher boiling organic compound or a mixture of these. Typical examples of effective agents are acetophenone, 3-pentanone, 2,4-pentanedione, ethylacetoacetate, 2-butanone plus benzil.
    Type: Grant
    Filed: November 1, 1983
    Date of Patent: February 26, 1985
    Inventors: Lloyd Berg, An-I Yeh
  • Separation of m-xylene from o-xylene by extractive distillation
    Patent number: 4488937
    Abstract: m-Xylene is difficult to separate from o-xylene by conventional rectification or distillation because of the close proximity of their boiling points. m-Xylene can be readily separated from o-xylene by using extractive distillation in which the extractive agent is ethyl-2-hydroxybenzoate; propoxypropanol puls 1,4-butanediol; sulfolane plus dimethylsulfoxide plus ethyl benzoate.
    Type: Grant
    Filed: April 11, 1984
    Date of Patent: December 18, 1984
    Inventors: Lloyd Berg, An-I Yeh
  • Separation of isopropyl ether from methyl ethyl ketone by extractive distillation
    Patent number: 4459178
    Abstract: Isopropyl ether cannot be completely removed from isopropyl ether - methyl ethyl ketone mixtures by distillation because of the presence of the minimum binary azeotrope. Isopropyl ether can be readily removed from mixtures containing it and methyl ethyl ketone by using extractive distillation in which the extractive distillation agent is a higher boiling oxygenated, nitrogenous and/or sulfur containing organic compound or a mixture of these. Typical examples of effective agents are sulfolane; ethylene carbonate plus dimethylsulfoxide; adiponitrile plus dimethylformamide plus glycerine.
    Type: Grant
    Filed: April 25, 1983
    Date of Patent: July 10, 1984
    Inventors: Lloyd Berg, An-I Yeh
  • Separation of isopropyl ether from acetone by extractive distillation
    Patent number: 4459179
    Abstract: Isopropyl ether cannot be completely removed from isopropyl ether-acetone mixtures by distillation because of the presence of the minimum binary azeotrope. Isopropyl ether can be readily removed from mixtures containing it and acetone by using extractive distillation in which the extractive distillation agent is a higher boiling oxygenated or nitrogenous organic compound or a mixture of these. Typical examples of effective agents are: dimethylsulfoxide; sulfolane and propylene glycol; glycerine, ethylene glycol and adiponitrile.
    Type: Grant
    Filed: January 6, 1983
    Date of Patent: July 10, 1984
    Inventors: Lloyd Berg, An-I Yeh