Patents by Inventor Zhufang Liu

Zhufang Liu 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: 20070100166
    Abstract: Carboxylic acid mixtures form unsymmetrical ketones in yields approaching statistical using zirconia catalysts promoted with Group IA and IIA elements. Active catalysts exist in their monoclinic or tetragonal but not cubic form. And the level of promoter loading is generally less than ten percent. The advantages of this catalyst over other ketonization catalysts include its high selectivity to ketones, its low formation of dehydrogenated byproducts, and its stability. The catalyst stability permits its regeneration to remove carbon accumulations by air oxidation. This regeneration restores full catalytic activity.
    Type: Application
    Filed: September 22, 2006
    Publication date: May 3, 2007
    Inventors: William Beavers, Alexey Ignatchenko, Zhufang Liu, Carey Ashcroft, Tracy White
  • Publication number: 20070093679
    Abstract: Mixed ketones are prepared from a mixture of carboxylic acids in a process with high selectivity by using an improved catalyst. The catalyst contains zirconium dioxide or zirconium dioxide and titanium dioxide, and a Group 1 or 2 metal silicate or phosphate salt. The new catalyst is more selective toward the formation of the mixed ketone, as opposed to a symmetrical ketone.
    Type: Application
    Filed: September 22, 2006
    Publication date: April 26, 2007
    Inventors: Alexey Ignatchenko, Michelle King, Zhufang Liu, Calvin Whiddon
  • Publication number: 20070088181
    Abstract: A catalyst for the preparation of ketones from carboxylic acids is described. The catalyst comprises a mixture of zirconium dioxide, titanium dioxide, and one or more metal oxides from Group 1 or 2 of the Periodic Table of Elements. The catalyst can operate at a lower temperature, reduce coke formation, and provide longer lifetime.
    Type: Application
    Filed: September 22, 2006
    Publication date: April 19, 2007
    Inventors: Alexey Ignatchenko, Michelle King, Zhufang Liu
  • Patent number: 7164038
    Abstract: In a process for reducing the visible color of a crude aromatic dicarboxylic acid containing colored contaminants, an aqueous ammonia solution of the crude aromatic dicarboxylic acid is prepared and contacted with hydrogen in a reactor in the presence of a heterogeneous metal-containing catalyst that includes a noble metal and a support. The process is carried out under conditions of temperature, pressure, and contact time effective to reduce the visible color of the aromatic dicarboxylic acid.
    Type: Grant
    Filed: February 14, 2006
    Date of Patent: January 16, 2007
    Assignee: Eastman Chemical Company
    Inventor: Zhufang Liu
  • Publication number: 20060278039
    Abstract: A process for removing metal species from a composition comprising contacting: a. an oligomer mixture stream comprising the monomers of a partially aromatic polyester polymer and at least one metal species, or b. a molten polyester polymer stream comprising partially aromatic polyester polymers and at least one metal species, with a non-catalytic porous material in the presence of hydrogen to produce a treated stream containing a reduced amount of at least one metal species. There is also provided a composition comprising a partially aromatic polyester polymer having an It.V. of at least 0.50 produced in a direct esterification melt phase process, from greater than 0 to less than 50 ppm antimony, and less than 40 ppm cobalt. There is also provided a composition comprising partially aromatic polyester polymers having an It.V. of at least 0.50 produced in an ester exchange melt phase process, from greater than zero to less than 5 ppm titanium, and less than 10 ppm manganese.
    Type: Application
    Filed: June 13, 2005
    Publication date: December 14, 2006
    Inventors: Zhufang Liu, Jeff Howell
  • Patent number: 7067615
    Abstract: A process comprising contacting a liquid polyester stream with hydrogen in the presence of a hydrogenation catalyst comprising a metal supported on the surface of silicon carbide at a metal dispersion of at least 0.5% or graphite at a metal dispersion of at least 10% to produce a treated liquid polyester stream. The treated stream may be polycondensed in the presence of a polycondensation catalyst to produce a polyester polymer having an It.V. of at least 0.55 dL/g. The liquid polyester stream desirably has a composition comprising: a) terephthalic acid residues, isophthalic acid residues, and/or naphthalenedicarboxylic acid residues and b) an average degree of polymerization of 0.5 to 20 and c) an acid number ranging from 5 to 600.
    Type: Grant
    Filed: June 13, 2005
    Date of Patent: June 27, 2006
    Assignee: Eastman Chemical Company
    Inventors: Zhufang Liu, Jeff Scott Howell, Charles Edwan Sumner, Jr.
  • Patent number: 6521765
    Abstract: Disclosed is a process for the preparation of 3-methyltetrahydrofuran (MeTHF) from 3-(hydroxymethyl)tetrahydrofuran (HOMeTHF) by contacting HOMeTHF with hydrogen in the presence of an acidic, supported catalyst comprising a Group VIII metal.
    Type: Grant
    Filed: April 18, 2002
    Date of Patent: February 18, 2003
    Assignee: Eastman Chemical Company
    Inventors: Alexey Victorovitch Ignatchenko, William Anthony Beavers, Zhufang Liu