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 isobutyl acetate from isobutanol by extractive distillation
    Patent number: 4724049
    Abstract: Isobutyl acetate cannot be completely removed from isobutyl acetate - isobutanol - water mixtures by distillation because of the presence of the minimum ternary axeotrope. Isobutyl acetate can be readily removed from mixtures containing it, isobutanol 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 dimethylformamide; dimethylsulfoxide, dimethylformamide and N,N-dimethylacetamide.
    Type: Grant
    Filed: June 26, 1986
    Date of Patent: February 9, 1988
    Inventors: Lloyd Berg, An-I Yeh
  • Separation of 2-butyl acetate from 2-butanol by extractive distillation
    Patent number: 4718988
    Abstract: 2-Butyl acetate cannot be completely removed from 2-butyl acetate-2-butanol-water mixtures by distillation because of the presence of the minimum ternary azeotrope. 2-butyl acetate can be readily removed from mixtures containing it, 2-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; dimethylformamide and ethylene glycol; acetamide, dimethylsulfoxide and ethylene glycol.
    Type: Grant
    Filed: March 27, 1986
    Date of Patent: January 12, 1988
    Inventors: Lloyd Berg, An-I Yeh
  • Separation of isopropyl acetate from isopropanol by extractive distillation
    Patent number: 4693789
    Abstract: Isopropyl acetate cannot be completely removed from isopropyl acetate - isopropanol - water mixtures by distillation because of the presence of the minimum ternary azeotrope. Isopropyl acetate can be readily removed from mixtures containing it, isopropanol and water by using extractive distillation in which the extractive agent is a higher boiling oxygenated or nitrogenous organic compound or a mixture of these. Typical examples of effective agents are diethanolamine; ethanolamine and N-methyl pyrrolidone; triethanolamine and N-methyl pyrrolidone.
    Type: Grant
    Filed: March 5, 1986
    Date of Patent: September 15, 1987
    Inventors: Lloyd Berg, An-I Yeh
  • Separation of n-amyl acetate from n-amyl alcohol by extractive distillation
    Patent number: 4690734
    Abstract: n-Amyl acetate cannot be completely removed from n-amyl acetate - n-amyl alcohol - water mixtures by distillation because of the presence of the minimum ternary azeotrope. n-Amyl acetate can be readily removed from mixtures containing it, n-amyl alcohol and water by using extractive distillation in which the extractive distillation agent is a higher boiling organic compound or a mixture of these. Typical examples of effective agents are ethylene glycol; propylene glycol and dimethylsulfoxide; 1,3-butanediol, dimethylformamide and acetamide.
    Type: Grant
    Filed: November 25, 1985
    Date of Patent: September 1, 1987
    Inventors: Lloyd Berg, An-I Yeh
  • Separation of n-propyl acetate from n-propanol and water by extractive distillation
    Patent number: 4676874
    Abstract: n-Propyl acetate cannot be completely removed from n-propyl acetate - n-propanol - water mixtures by distillation because of the presence of the minimum ternary azeotrope. n-Propyl acetate can be readily removed from mixtures containing it, n-propanol and water 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 N-methylpyrrolidone; triethanolamine; N-methylpyrrolidone and ethylene glycol.
    Type: Grant
    Filed: November 7, 1985
    Date of Patent: June 30, 1987
    Inventors: Lloyd Berg, An-I Yeh
  • Separation of m-xylene from o-xylene by extractive distillation
    Patent number: 4676875
    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 dimethylformamide; dimethylformamide and 1,4-butanediol; dimethylformamide, adiponitrile and dihexyl phthalate.
    Type: Grant
    Filed: January 6, 1986
    Date of Patent: June 30, 1987
    Inventors: Lloyd Berg, An-I Yeh
  • Separation of m-xylene from o-xylene by extractive distillation with adiponitrile and mixtures thereof
    Patent number: 4676872
    Abstract: m-Xylene is difficult to separate from o-xylene by conventional distillation or rectification 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 adiponitrile or a mixture of it with certain high boiling organic compounds. Typical examples of effective agents are: adiponitrile; adiponitrile and 1,4-butanediol; adiponitrile, ethylene carbonate and benzyl alcohol.
    Type: Grant
    Filed: April 21, 1986
    Date of Patent: June 30, 1987
    Inventors: Lloyd Berg, An-I Yeh
  • Separation of m-xylene from o-xylene by extractive distillation with polychloro compounds
    Patent number: 4673465
    Abstract: m-Xylene is difficult to separate from o-xylene by conventional distillation or rectification 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 a mixture polychloro aromatic compounds. Typical examples of effective agents are 2,3,4,6-tetrachlorophenol and p-dichlorobenzene; dimethyltetrachloroterephthalate, 2,3,4,6-tetrachlorophenol and 1,2,4,5-tetrachlorobenzene; 2,4,5-trichlorophenol, benzene hexachloride, o-dichlorobenzene and dioctyl phthalate.
    Type: Grant
    Filed: April 21, 1986
    Date of Patent: June 16, 1987
    Inventors: Lloyd Berg, An-I Yeh
  • Dehydration of propanoic acid by extractive distillation
    Patent number: 4670105
    Abstract: Propanoic acid cannot be completely removed from propanoic-water mixtures by distillation because of the presence of the minimum azeotrope. Propanoic acid can be readily removed from mixtures containing it and water by using extractive distillation in which the extractive distillation agent is an acid amide. Typical examples of effective agents are acetamide; dimethylformamide and methyl glutaronitrile; formamide, adiponitrile and N,N-dimethylacetamide.
    Type: Grant
    Filed: April 7, 1986
    Date of Patent: June 2, 1987
    Inventors: Lloyd Berg, An-I Yeh
  • Separation of n-amyl acetate and water from n-amyl alcohol by extractive distillation
    Patent number: 4670106
    Abstract: n-Amyl acetate cannot be completely removed from n-amyl acetate - n-amyl alcohol - water mixtures by distillation because of the presence of the minimum ternary azeotrope. n-Amyl acetate can be readily removed from mixtures containing it, n-amyl alcohol and water by using extractive distillation in which the extractive distillation agent is a higher boiling organic compound or a mixture of these. Typical examples of effective agents are dimethylsulfoxide; N,N-dimethylacetamide and dimethylsulfoxide; dimethylformamide, N,N-dimethylacetamide and acetamide.
    Type: Grant
    Filed: December 2, 1985
    Date of Patent: June 2, 1987
    Inventors: Lloyd Berg, An-I Yeh
  • Separation of isopropyl ether from isopropanol and water by extractive distillation
    Patent number: 4666563
    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 glycol, glycol ether or a mixture of them. Typical examples of effective agents are ethylene glycol, propylene glycol, diethylene glycol diethyl ether plus propylene glycol ethyl ether.
    Type: Grant
    Filed: November 20, 1985
    Date of Patent: May 19, 1987
    Inventors: Lloyd Berg, An-I Yeh
  • Dehydration of ethanol by extractive distillation
    Patent number: 4654123
    Abstract: Water cannot be completely removed from ethanol by distillation because of the presence of the minimum azeotrope. Ethanol can be readily dehydrated by using extractive distillation in which the water is removed as overhead product and the ethanol and extractive agent as bottoms and subsequently separated by conventional rectification. Typical examples of suitable extractive agents are hexahydrophthalic anhydride; methyl tetrahydrophthalic anhydride and pentanol-1; trimellitic anhydride, ethyl salicylate and resorcinol.
    Type: Grant
    Filed: January 2, 1986
    Date of Patent: March 31, 1987
    Inventors: Lloyd Berg, An-I Yeh
  • Apparatus for timely controlling the sound characteristic of a signaling means of a voice communication device
    Patent number: 4644106
    Abstract: An automatic telephone silencer and volume controller having a microprocessor for storing time and volume information and for timely controlling the sound characteristics of a telephone ringer in accordance with the time and volume information stored. The time and volume information may be entered into the microprocessor by a suitable keyboard. Each time entry has associated with it a volume entry so that the telephone will ring at the prescribed volume from that time until the time denoted by the next time entry.
    Type: Grant
    Filed: January 10, 1985
    Date of Patent: February 17, 1987
    Assignee: Inventa electronics Co., Ltd.
    Inventor: Kou-I Yeh
  • Dehydration of formic acid by extractive distillation
    Patent number: 4642166
    Abstract: Formic acid cannot be completely removed from formic acid - water mixtures by distillation because of the presence of the maximum azeotrope. Formic acid can be readily removed from mixtures containing it and water by using extractive distillation in which the extractive distillation agent is a sulfone. Typical examples of effective agents are thiophan sulfone; dimethyl sulfone and adiponitrile; phenyl sulfone, adiponitrile and acetophenone.
    Type: Grant
    Filed: February 10, 1986
    Date of Patent: February 10, 1987
    Inventors: Lloyd Berg, An-I Yeh
  • Separation of isobutyl acetate from isobutanol by extractive distillation
    Patent number: 4642167
    Abstract: Isobutyl acetate cannot be completely removed from isobutyl acetate--isobutanol--water mixtures by distillation because of the presence of the minimum ternary azeotrope. Isobutyl acetate can be readily removed from mixtures containing it, isobutanol 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; dimethylformamide and dimethylsulfoxide; acetamide, dimethylformamide and dipropylene glycol.
    Type: Grant
    Filed: March 7, 1985
    Date of Patent: February 10, 1987
    Inventors: Lloyd Berg, An-I Yeh
  • Dehydration of ethanol by extractive distillation
    Patent number: 4631115
    Abstract: Water cannot be completely removed from ethanol by distillation because of the presence of the minimum azeotrope. Ethanol can be readily dehydrated by using extractive distillation in which the water is removed as overhead product and the ethanol and extractive agent as bottoms and subsequently separated by conventional rectification. Typical examples of suitable extractive agents are methyl benzoate; trimellitic anhydride and methyl benzoate; dipropylene glycol dibenzoate, ethyl salicylate and resorcinol.
    Type: Grant
    Filed: December 23, 1985
    Date of Patent: December 23, 1986
    Inventors: Lloyd Berg, An-I Yeh
  • Separation of methyl acetate from methanol by extractive distillation
    Patent number: 4597834
    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 dimethylformamide; dimethylsulfoxide plus tetraethylene glycol, dimethylsulfoxide plus 1,5-pentanediol plus 1,6-hexanediol.
    Type: Grant
    Filed: February 17, 1984
    Date of Patent: July 1, 1986
    Inventors: Lloyd Berg, An-I Yeh
  • Separation of n-propyl acetate from n-propanol by extractive distillation
    Patent number: 4592805
    Abstract: n-Propyl acetate cannot be completely removed from n-propyl acetate - n-propanol - water mixtures by distillation because of the presence of the minimum ternary azeotrope. n-Propyl acetate can be readily removed from mixtures containing it, n-propanol 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. Examples of effective agents are N,N-dimethylacetamide; acetamide and triethylene glycol; acetamide and N,N-dimethylacetamide and triethanolamine.
    Type: Grant
    Filed: December 14, 1984
    Date of Patent: June 3, 1986
    Inventors: Lloyd Berg, An-I Yeh
  • Separation of m-xylene from o-xylene by extractive distillation
    Patent number: 4585526
    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 comprises propoxypropanol; propoxypropanol and 1,4-butanediol; ethyl benzoate and ethylene glycol phenyl ether and benzyl alcohol.
    Type: Grant
    Filed: October 1, 1984
    Date of Patent: April 29, 1986
    Inventors: Lloyd Berg, An-I Yeh
  • Separation of isopropyl ether from isopropanol and water by extractive distillation
    Patent number: 4566948
    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 dimethylsulfoxide with or without a mixture of higher boiling oxygenated and/or nitrogenous organic compounds. Typical examples are dimethylsulfoxide; dimethylsulfoxide and ethylene glycol; dimethylsulfoxide, dimethylformamide and 1,4-butanediol.
    Type: Grant
    Filed: December 20, 1984
    Date of Patent: January 28, 1986
    Inventors: Lloyd Berg, An-I Yeh