Patents by Inventor Andrius Algimantas Naujokas

Andrius Algimantas Naujokas 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).

  • Recovery of ester monomer from polyester resins
    Patent number: 5952520
    Abstract: There is described a process for improving the yield of diester monomer recovered from the depolymerization of polyethylene terephthalate by converting a mixture of dimethyl terephthalate and methylhydroxyethyl terephthalate to predominantly dimethyl terephthalate by treating that mixture with a mixture of an alcohol and an alkali metal hydroxide at a temperature up to the boiling point of the alcohol.
    Type: Grant
    Filed: July 10, 1996
    Date of Patent: September 14, 1999
    Assignee: Eastman Kodak Company
    Inventor: Andrius Algimantas Naujokas
  • Purification of ethylene glycol recovered from polyester resins
    Patent number: 5770778
    Abstract: There is described a process for purifying ethylene glycol recovered from scrap polyester by contacting the recovered ethylene glycol with, in either order, a first adsorbent that has a high affinity for polar contaminants and a second adsorbent that has a high affinity for non-polar contaminants.
    Type: Grant
    Filed: July 10, 1996
    Date of Patent: June 23, 1998
    Assignee: Eastman Kodak Company
    Inventor: Andrius Algimantas Naujokas
  • Recovery of components from polyester resins
    Patent number: 5747547
    Abstract: There is described a process and apparatus for the depolymerization of polyester resins, such as polyethylene terephthalate into component monomers using a countercurrent or crossflow reactor.
    Type: Grant
    Filed: July 26, 1996
    Date of Patent: May 5, 1998
    Assignee: Eastman Kodak Company
    Inventors: Andrius Algimantas Naujokas, William James Gamble
  • Purification of ethylene glycol recovered from polyester resins
    Patent number: 5672780
    Abstract: There is described a process for removing dimethyl terephthalate contaminants from ethylene glycol. The process comprises distilling ethylene glycol in the presence of an ester exchange catalyst to cause reaction between ethylene glycol and dimethyl terephthalate to form compounds that are less volatile than either ethylene glycol or dimethyl terephthalate, such as bishydroxyethyl terephthalate.
    Type: Grant
    Filed: July 26, 1996
    Date of Patent: September 30, 1997
    Assignee: Eastman Kodak Company
    Inventors: William James Gamble, Andrius Algimantas Naujokas
  • Recovery of terephthalate diesters from glycol residues
    Patent number: 5672729
    Abstract: There is described a process for improving the yield of difunctional ester in a process of recovering monomer components from condensation-type polyester resins such as polyethylene terephthalate by converting terephthalyl monomers and oligomers present in ethylene glycol still bottoms to terephthalate diester, such as dimethyl terephthalate. This is accomplished by treating the terephthalyl monomers and oligomers with a mixture of an alcohol and an alkali metal hydroxide at a temperature up to the boiling point of the alcohol.
    Type: Grant
    Filed: August 14, 1996
    Date of Patent: September 30, 1997
    Assignee: Eastman Kodak Company
    Inventor: Andrius Algimantas Naujokas
  • Recovery of components from polyester resins
    Patent number: 5654470
    Abstract: There is described a process for the depolymerization of polyethylene terephthalate into component monomers at ambient pressure. Monomer solids that deposit during cooling, as part of the recovery operation, are removed using a scraped wall heat exchanger.
    Type: Grant
    Filed: July 26, 1996
    Date of Patent: August 5, 1997
    Assignee: Eastman Kodak Company
    Inventors: Andrius Algimantas Naujokas, William James Gamble