Patents by Inventor Rei-Yu J. Hwan

Rei-Yu J. Hwan 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: 5565068
    Abstract: In the multistage distillation of a methyl tertiary butyl ether reaction product comprising methyl tertiary butyl ether, tertiary butyl alcohol, methanol, isobutylene and water, the methyl tertiary butyl ether reaction product is separated in a primary methyl tertiary butyl ether distillation column into a lower boiling methyl tertiary butyl ether fraction and a higher boiling aqueous tertiary butyl alcohol fraction; the lower boiling aqueous tertiary butyl alcohol fraction is separated in a tertiary butyl alcohol distillation column into a vaporized overhead tertiary butyl alcohol fraction and a higher boiling water fraction; cooling water is charged to the reflux condenser for the tertiary butyl alcohol distillation column to liquify the vaporized, overhead tertiary butyl alcohol fraction and to convert the cooling water to wet steam, and the wet steam is independently charged to the reboiler for the primary methyl tertiary butyl ether distillation zone to supply the heat necessary for the distillation to b
    Type: Grant
    Filed: June 16, 1995
    Date of Patent: October 15, 1996
    Assignee: Texaco Development Corporation
    Inventors: Stuart J. Parker, Arlen G. Sliger, Rei-Yu J. Hwan
  • Patent number: 5563301
    Abstract: Methyl tertiary butyl ether is sequentially prepared from tertiary butyl alcohol and methanol by:passing tertiary butyl alcohol and methanol through a primary reaction zone to form a primary etherification reaction product comprising unreacted methanol, unreacted tertiary butyl alcohol, water, dimethyl ether, isobutylene and methyl tertiary butyl ether;separating the primary etherification reaction product into a methanol recycle fraction, a tertiary butyl alcohol recycle fraction, an isobutylene fraction and a methyl tertiary butyl ether product fraction;recycling the methanol recycle fraction and the tertiary butyl alcohol recycle fraction to the methyl tertiary butyl ether etherification reaction zone;passing at least a portion of said isobutylene fraction together with added methanol through a secondary reaction zone to form a secondary etherification reaction product comprising water, methanol, isobutylene, DME, methyl tertiary butyl ether and tertiary butyl alcohol; andrecovering the methyl tertiary but
    Type: Grant
    Filed: November 28, 1994
    Date of Patent: October 8, 1996
    Assignee: Texaco Development Corp.
    Inventors: Kyle L. Preston, Lawrence E. Tillotson, Rei-Yu J. Hwan
  • Patent number: 5527970
    Abstract: Disclosed is an improved process for preparing ethyl t-butyl ether in one-step which comprises reacting tertiary butanol and ethanol in the presence of a catalyst consisting essentially of a macroreticular acid resin or a pentasil zeolite at a temperature of about 40.degree.-140.degree. C. and atmospheric pressure to about 500 psig.
    Type: Grant
    Filed: February 2, 1995
    Date of Patent: June 18, 1996
    Assignee: Texaco Chemical Inc.
    Inventors: Rei-Yu J. Hwan, John F. Knifton, Brian L. Benac
  • Patent number: 5395982
    Abstract: An impure methyl tertiary butyl ether product contaminated with isobutylene, methanol and water is purified by continuous counter-current contact with water and isobutylene in a counter-current contact extraction tower to provide an overhead extract comprising isobutylene, methyl tertiary butyl ether and water and a raffinate comprising methanol, water and a minor amount of methyl tertiary butyl ether, the overhead raffinate being separated in a methyl tertiary butyl ether purification distillation zone into a lighter distillation fraction comprising isobutylene and water and a heavier distillation fraction consisting essentially of methyl tertiary butyl ether, the lighter distillation fraction being decanted to remove water and to provide a distillate isobutylene fraction that is charged to a surge drum from which isobutylene is returned to the contact tower.
    Type: Grant
    Filed: November 5, 1993
    Date of Patent: March 7, 1995
    Assignee: Texaco Chemical Company
    Inventors: John R. Cassata, Stuart J. Parker, Rei-Yu J. Hwan, Catherine J. Conkwright
  • Patent number: 5354912
    Abstract: An isobutylene feed mixture comprising MTBE, isobutylene and methanol is passed through an isobutylene conversion zone to form an isobutylene conversion product comprising unreacted methanol, unreacted isobutylene, dimethyl ether, MTBE and water, then charged to a countercurrent methanol extraction zone and contacting with water to provide an overhead raffinate comprising isobutylene, MTBE and water, and an extract comprising methanol, water, MTBE, isobutylene and dimethyl ether;the extract is distilled to provide a vaporized overhead fraction comprising MTBE, isobutylene, methanol, and dimethyl ether;the vaporized overhead fraction is partially condensed and from about 5 to 10 wt. % of the mixed phase condensate is vented to thereby provide a liquid condensate that is substantially free from dissolved dimethyl ether, and the condensate is recycled to the methanol extraction zone.
    Type: Grant
    Filed: June 1, 1993
    Date of Patent: October 11, 1994
    Assignee: Texaco Chemical Company
    Inventors: Rei-Yu J. Hwan, Charles J. Kruse
  • Patent number: 5243091
    Abstract: A method for the preparation of methyl tertiary butyl ether is provided wherein a mixture of methanol and substantially peroxides-free tertiary butyl alcohol are catalytically reacted to form a reaction product that is separated into a first lighter distillation fraction comprising isobutylene, methanol and methyl tertiary butyl ether and a second heavier distillation fraction comprising methanol, tertiary butyl alcohol and water, wherein the first distillation fraction and a first recycle isobutylene fraction are reacted to form an isobutylene conversion product that is charged, together with recycle isobutylene to a methanol extraction zone and countercurrently contacted with water to provide an overhead extract comprising aqueous isobutylene, and wherein the isobutylene is recovered and recycled.
    Type: Grant
    Filed: November 19, 1992
    Date of Patent: September 7, 1993
    Assignee: Texaco Chemical Company
    Inventors: Charles J. Kruse, Rei-Yu J. Hwan, Kyle L. Preston, Feng-Ran Sheu