Patents by Inventor Linda S. Cheng

Linda S. Cheng 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).

  • Publication number: 20120264994
    Abstract: A process for separating para-xylene from a mixture of C8 alkylaromatics comprises contacting the mixture of C8 alkylaromatics with a zeolitic binder-converted composition comprising (a) a zeolite X composition having at least a first zeolite X having a mean diameter not greater than 2.7 microns, and a second zeolite X, wherein the second zeolite X is obtained by converting a binder material to the second zeolite X and the binder material is in a range from 5 to 50 wt % of the zeolite X composition; and (b) an unconverted binder material content, after conversion to the second zeolite X is complete, in a range from 0 to 3 wt % of the zeolite X composition. The zeolite X composition has an average Si/AI framework mole ratio in a range from 1.0 to 1.5, and a relative LTA intensity not greater than 1.0, as determined by x-ray diffraction (XRD).
    Type: Application
    Filed: March 22, 2012
    Publication date: October 18, 2012
    Applicant: UOP LLC
    Inventors: Jack E. Hurst, Linda S. Cheng, Robert W. Broach
  • Publication number: 20120264993
    Abstract: A zeolitic binder-converted composition comprising (a) a zeolite X composition having at least a first zeolite X having a mean diameter not greater than 2.7 microns, and a second zeolite X, wherein the second zeolite X is obtained by converting a binder material to the second zeolite X and the binder material is in a range from 5 to 50 wt % of the zeolite X composition; and (b) an unconverted binder material content, after conversion to the second zeolite X is complete, in a range from 0 to 3 wt % of the zeolite X composition. The zeolite X composition has an average Si/Al framework mole ratio in a range from 1.0 to 1.5, and a relative LTA intensity not greater than 1.0, as determined by x-ray diffraction (XRD).
    Type: Application
    Filed: March 22, 2012
    Publication date: October 18, 2012
    Applicant: UOP LLC
    Inventors: Jack E. Hurst, Linda S. Cheng, Robert W. Broach
  • Publication number: 20120264992
    Abstract: A zeolite X having (a) a Si/Al framework mole ratio in a range from 1.0 to 1.5; (b) a mean diameter not greater than 2.7 microns; and (c) a relative LTA intensity not greater than 0.35, as determined by x-ray diffraction (XRD). The relative LTA intensity is calculated as 100 times the quotient of a sample LTA XRD intensity divided by a reference XRD intensity of an LTA-type zeolite material. The intensities are summed for each LTA peak with Miller indices of (2 0 0), (4 2 0), and (6 2 2) at 7.27±0.16°, 16.29±0.34° and 24.27±0.50° 2?.
    Type: Application
    Filed: March 22, 2012
    Publication date: October 18, 2012
    Applicant: UOP LLC
    Inventors: Jack E. Hurst, Linda S. Cheng, Robert W. Broach
  • Publication number: 20120247334
    Abstract: Binderless BaKX zeolitic adsorbents, methods for their production, and adsorptive separation using the adsorbents are provided. An adsorbent comprises a first Zeolite X having a silica to alumina molar ratio of from about 2.0 to about 3.0; a binder-converted Zeolite X wherein a ratio of the binder-converted Zeolite X to the first Zeolite X ranges from about 10:90 to about 20:80 by weight; and barium and potassium at cationic exchangeable sites within the binderless BaKX zeolitic adsorbent. Potassium ranges from about 0.9 wt % to about 1.5 wt % and barium ranges from about 30 wt % to about 34 wt % of the binderless BaKX zeolitic adsorbent.
    Type: Application
    Filed: March 21, 2012
    Publication date: October 4, 2012
    Applicant: UOP LLC
    Inventors: Jack E. Hurst, Linda S. Cheng
  • Patent number: 6406521
    Abstract: A process is provided for the concentration and recovery of propylene from propane by a pressure swing adsorption (PSA) process using an adsorbent comprising AlPO-14. A PSA process is used to remove propylene from a C3 hydrocarbon stream comprising propylene and propane. The PSA process of the present invention can be employed in petroleum refining and petrochemical processes to purify and separate propylene from mixtures of propylene and propane without fractionation.
    Type: Grant
    Filed: November 30, 1999
    Date of Patent: June 18, 2002
    Inventors: Linda S. Cheng, Joel Padin, Salil U. Rege, Stephen T. Wilson, Ralph T. Yang
  • Publication number: 20020007101
    Abstract: A process is provided for the concentration and recovery of ethylene and heavier components from an oxygenate conversion process. A separation process such as a pressure swing adsorption (PSA) process is used to remove hydrogen and methane from a demethanizer overhead stream comprising hydrogen, methane and C2 hydrocarbons and subsequently return the recovered C2 hydrocarbons to be admixed with the effluent from the oxygenate conversion process. This integration of a separation zone with a fractionation scheme in an ethylene recovery scheme using an initial deethanizer zone resulted in significant capital and operating cost savings by the elimination of cryogenic ethylene-based refrigeration from the overall recovery scheme.
    Type: Application
    Filed: July 19, 2001
    Publication date: January 17, 2002
    Inventors: John J. Senetar, Lawrence W. Miller, Linda S. Cheng, Mark M. Davis
  • Patent number: 6296688
    Abstract: A vacuum swing adsorption process is provided for the separation of propylene from a feedstream comprising propylene and propane using an adsorbent comprising AlPO-14 to produce a high purity propylene product stream at high recovery. The vacuum swing adsorption process of the present invention can be employed in a variety of petroleum refining and petrochemical processes to purify and separate propylene from mixtures of propylene and propane alone or in combination with fractionation.
    Type: Grant
    Filed: November 30, 1999
    Date of Patent: October 2, 2001
    Assignee: UOP LLC
    Inventors: Linda S. Cheng, Stephen T. Wilson
  • Patent number: 6293999
    Abstract: A process is provided for the concentration and recovery of propylene from propane using an adsorbent comprising AlPO-14 at adsorption temperatures less than 120° C. and an adsorption pressure comprising a propylene partial pressure between about 0.5 bar and about 4 bar. The AlPO-14 adsorbent can be employed as a selective adsorbent for the separation of propylene from mixtures thereof with propane in vacuum swing adsorption processes, thermal swing adsorption processes, and combinations thereof. A simulated moving bed process using vacuum swing adsorption is used to remove propylene from a C3 hydrocarbon stream comprising propylene and propane and recover a high purity propylene product at a high recovery rate. The simulated moving bed vacuum swing adsorption process of the present invention can be employed in a variety of petroleum refining and petrochemical processes to purify and separate propylene from mixtures of propylene and propane alone or in combination with fractionation.
    Type: Grant
    Filed: November 30, 1999
    Date of Patent: September 25, 2001
    Assignee: UOP LLC
    Inventors: Linda S. Cheng, Stephen T. Wilson