Purification Or Recovery Patents (Class 560/78)
  • Patent number: 10301334
    Abstract: A method for preparing a stabilizer containing phosphate ester, including following steps: (1) distributing a compound containing phosphorous and oxide in polar aprotic solvent to obtain a mixture; (2) adding bis(2-hydroxyethyl) terephthalate (BHET) into the mixture to carry out a reaction so as to obtain a solution; and (3) hydrolyzing the solution to obtain a stabilizer containing phosphate ester, where the stabilizer includes compounds represented by the following formulas (I) and (II): where X1, X2 and X3 are independently selected from the moiety represented by following formula (III), and R1 and R2 are independently selected from one of the linear or branched alkylene radicals comprising 2 to 4 carbon atoms The method yields a phosphate ester containing a phosphate monoester and a phosphate diester of a high content and only a minor amount of phosphoric acid in the absence of phosphate triester without the step of extraction.
    Type: Grant
    Filed: June 25, 2018
    Date of Patent: May 28, 2019
    Assignee: Far Eastern New Century Corporation
    Inventors: Hsin-Hui Cheng, Cheng-Ting Wang, Der-Ren Hwang, Chih-Chien Lin
  • Patent number: 10213706
    Abstract: A process and an apparatus for the purification of a crude acrylic acid composition containing maleic anhydride as an impurity comprising the following steps: (a) carrying out at least one dynamic melt crystallization stage (14, 14a, 14b, 14c, 14d) with the crude acrylic acid composition to prepare a first purified acrylic acid composition and a first residue containing at least 3.5% by weight maleic anhydride, (b) adding a solvent (26) which is capable of dissolving maleic anhydride to the first residue in an amount that the weight ratio of the solvent to the maleic anhydride is 0.3 or more to prepare a ratio-adjusted residue and (c) carrying out at least one further dynamic melt crystallization stage and/or at least one static melt crystallization stage (18, 18a, 18b) with the ratio-adjusted residue to prepare a second purified acrylic acid composition and a second residue.
    Type: Grant
    Filed: July 30, 2015
    Date of Patent: February 26, 2019
    Assignee: Sulzer Chemtech AG
    Inventors: Matthias Schäfer, Andrzej Kuszlik, Florian Lippuner, Herbert Engstler
  • Patent number: 9981902
    Abstract: The current invention pertains to a process for producing a terephthalate ester comprising: providing reclaimed carpet material comprising a polyester component; and reacting the polyester component with an alcohol having from 6 to 20 carbon atoms and under conditions effective to produce a terephthalate ester; wherein 15-40% of the mass of the terephthalate ester is derived from the polyester present in the reclaimed carpet material.
    Type: Grant
    Filed: October 24, 2016
    Date of Patent: May 29, 2018
    Assignee: Columbia Insurance Company
    Inventor: John Charles Mastrangelo
  • Patent number: 8987499
    Abstract: Compositions including a C6 to C13 phthalate ester containing titanium but in an amount less than 0.01 ppm by wt of titanium, prepared by titanium catalyzed esterification, and containing from 0.1 to 2.0 wt % of an antioxidant, are provided.
    Type: Grant
    Filed: February 28, 2011
    Date of Patent: March 24, 2015
    Assignee: ExxonMobil Chemical Patents Inc.
    Inventors: Brady Compton, John Lyford, IV, Nicolaas A. De Munk, Aad Gerrit Oskam, Allen D. Godwin, Leendert Johannes Van Dop
  • Patent number: 8829227
    Abstract: Esters produced by the catalyzed reaction of alcohols and acids or anhydrides are neutralized by treatment with an aqueous alkaline alkali metal salt solution in an amount that provides less than a stoichiometric amount of alkali metal salt in relation to the acidity of the crude ester and the amount of water present during the treatment is from 0.8 to 1.4 wt % of water based on the weight of crude ester. When using titanium as the esterification catalyst, the ester resulting from this process contains less than 0.01 ppm by weight of titanium residue, so that it is storage stable when stored in the presence of an antioxidant.
    Type: Grant
    Filed: May 24, 2006
    Date of Patent: September 9, 2014
    Assignee: ExxonMobil Chemical Patents Inc.
    Inventors: Brady Compton, John Lyford, IV, Nicolaas Anthony De Munck, Aad Gerrit Oskam, Allen David Godwin, Leendert Johannes Van Dop
  • Patent number: 8729292
    Abstract: The invention relates to a raw ester of an esterification reaction catalyzed by a metal-containing esterification catalyst generated by a) mixing the raw ester at a temperature T of more than 100° C. under a pressure p that is equal to or greater than the vapor pressure of water at the temperature T with an aqueous base, b) relaxing the ester-base mixture and evaporating water, c) mixing the obtained fluid phase with water forming a water-in-oil emulsion, d) distilling water out of said emulsion and e) filtering the ester. Said method results in esters having low acid value and residues accrue in easily filterable form in the solid catalyst residues.
    Type: Grant
    Filed: December 15, 2009
    Date of Patent: May 20, 2014
    Assignee: BASF SE
    Inventors: Katrin Friese, Walter Disteldorf, Jarren Peters, Günther Golfier
  • Patent number: 8541616
    Abstract: An MHT reactor is added to a DMT process to eliminate the majority of the DMT/MHT recycle back to the DMT reactor, allowing for an increase in capacity to the DMT reactors.
    Type: Grant
    Filed: January 21, 2010
    Date of Patent: September 24, 2013
    Assignee: Eastman Chemical Company
    Inventors: Laura Ellen Bustamante, William Lee Cook, Brent Alan Tennant, Ashfaq Shaikh, Joseph Luther Parker, Richard Andrew Virost, Michael Visneski
  • Publication number: 20120041225
    Abstract: The present invention provides a means for the rapid selection of optimum resolving agents and solvents, combinations and conditions to separate optical isomers. The present invention combinedly describes and automates a full lifecycle of chiral separation method development and optimization through a series of kits and procedures providing screening, automation for screening, racemate recovery, enantiomer preparation, and method optimization.
    Type: Application
    Filed: October 21, 2011
    Publication date: February 16, 2012
    Inventor: Niteen A. Vaidya
  • Publication number: 20110251419
    Abstract: The invention relates to a raw ester of an esterification reaction catalyzed by a metal-containing esterification catalyst generated by a) mixing the raw ester at a temperature T of more than 100° C. under a pressure p that is equal to or greater than the vapor pressure of water at the temperature T with an aqueous base, b) relaxing the ester-base mixture and evaporating water, c) mixing the obtained fluid phase with water forming a water-in-oil emulsion, d) distilling water out of said emulsion and e) filtering the ester. Said method results in esters having low acid value and residues accrue in easily filterable form in the solid catalyst residues.
    Type: Application
    Filed: December 15, 2009
    Publication date: October 13, 2011
    Applicant: BASF SE
    Inventors: Katrin Friese, Walter Disteldorf, Mannheim Germany, Günther Golfer
  • Patent number: 8017797
    Abstract: A method for efficiently producing 4-(hydroxymethylphosphinyl)-2-oxobutanoic acid, useful as a production intermediate of herbicide L-AMPB. The method comprises using a compound represented by the below formula (4): (4) where R1 represents a C1-4 alkyl group, arylmethyl group, or substituted arylmethyl group.
    Type: Grant
    Filed: March 21, 2008
    Date of Patent: September 13, 2011
    Assignee: Meiji Seika Kaisha Ltd.
    Inventors: Nobuto Minowa, Nozomu Nakanishi, Masaaki Mitomi
  • Patent number: 7959713
    Abstract: Process for purifying and cooling a gas stream comprising a dialkyl ester A) of an aromatic dicarboxylic acid, which comprises treating the gas stream with an aliphatic dihydroxy compound B) at a temperature less than/equal to the melting point of the dialkyl ester A) in a 1st stage and treating the gas stream with an aliphatic dihydroxy compound B) at above the melting point of the dihydroxy compound B) in at least one 2nd stage.
    Type: Grant
    Filed: March 17, 2005
    Date of Patent: June 14, 2011
    Assignee: BASF Aktiengesellschaft
    Inventors: Jan-Martin Löning, Manfred Heckmann, Karl Hölemann, Thomas Heitz
  • Patent number: 7919649
    Abstract: Esters produced by the catalyzed reaction of alcohols and acids or anhydrides are neutralized by treatment with an aqueous alkaline alkali metal salt solution in an amount that provides less than a stoichiometric amount of alkali metal salt in relation to the acidity of the crude ester and the amount of water present during the treatment is from 0.7 to 1.4 wt % of water based on the weight of crude ester. When using titanium as the esterification catalyst, the ester resulting from this process contains less than 0.01 ppm by weight of titanium residue, so that it is storage stable when stored in the presence of an antioxidant.
    Type: Grant
    Filed: April 5, 2006
    Date of Patent: April 5, 2011
    Assignee: ExxonMobile Chemical Patents Inc.
    Inventors: Brady Compton, John Lyford, IV, Nicolaas A. De Munck, Aad Gerrit Oskam, Allen D. Godwin, Leendert Johannes Van Dop
  • Patent number: 7884230
    Abstract: A process for the chemical recycling of post consumption polyethylene terephthalate which includes the steps of performing the depolymerization of polyethylene terephthalate based upon a hydrolysis reaction which causes a rupture in of the ester bonds formed between the polymer precursors of terephthalic acid and ethylene glycol at the time of polymerization to recover terephthalic acid and ethylene glycol. The advantages of the present process are the working conditions at low to moderate pressure, at temperatures of 215 to 450° C., allowing the process to reach the energy level required to achieve the desired polyethylene terephthalate hydrolysis and simultaneously promoting the separation and purification of the terephthalic acid and ethylene glycol formed in this hydrolysis reaction.
    Type: Grant
    Filed: August 25, 2005
    Date of Patent: February 8, 2011
    Assignees: BRASKEM S.A.
    Inventors: Luiz Alberto Jermolovicius, Edmilson Renato De Castro
  • Publication number: 20100210867
    Abstract: An MHT reactor is added to a DMT process to eliminate the majority of the DMT/MHT recycle back to the DMT reactor, allowing for an increase in capacity to the DMT reactors.
    Type: Application
    Filed: January 21, 2010
    Publication date: August 19, 2010
    Applicant: EASTMAN CHEMICAL COMPANY
    Inventors: Laura Ellen Bustamante, William Lee Cook, Brent Alan Tennant, Ashfaq Shaikh, Joseph Luther Parker, Richard Andrew Virost, Michael Visneski
  • Publication number: 20090171113
    Abstract: A process for ethanolysis of PET is disclosed wherein a feed comprising PET is reacted with ethanol and recovering ethylene glycol and an aromatic diethyl ester such as diethyl isophthalate and/or diethyl terephthalate. PET, or a terpolymer comprising terephthalate monomer and ethylene glycol monomers, is reacted with ethanol and ethanol, diethyl terephthalate, ethylene glycol and optionally diethyl isophthalate are recovered. Recovered diethyl components can be subjected to liquid-phase oxidation to produce aromatic carboxylic acid. Acetic acid may also produced via liquid-phase oxidation of recovered diethyl components. The aromatic carboxylic acid can be used to form polymer.
    Type: Application
    Filed: December 30, 2006
    Publication date: July 2, 2009
    Applicant: BP Corporation North America Inc.
    Inventors: Ronald L. Anderson, David L. Sikkenga
  • Publication number: 20080275267
    Abstract: Esters produced by the catalyzed reaction of alcohols and acids or anhydrides are neutralized by treatment with an aqueous alkaline alkali metal salt solution in an amount that provides less than a stoichiometric amount of alkali metal salt in relation to the acidity of the crude ester and the amount of water present during the treatment is from 0.8 to 1.4 wt % of water based on the weight of crude ester. When using titanium as the esterification catalyst, the ester resulting from this process contains less than 0.01 ppm by weight of titanium residue, so that it is storage stable when stored in the presence of an antioxidant.
    Type: Application
    Filed: May 24, 2006
    Publication date: November 6, 2008
    Inventors: Brady Compton, John Lyford, Nicolaas Anthony De Munck, Aad Gerrit Oskam, Allen David Godwin, Leendert Johannes Van Dop
  • Patent number: 7306738
    Abstract: There is provided a method for deionizing a decomposition produced solution resulting from decomposition of a polyester by ethylene glycol. The ester interchange reaction and hydrolysis reaction along with cation removing treatment of a decomposition product resulting from decomposition of a polyester by ethylene glycol are suppressed. Thereby, a method for deionizing the decomposition produced solution with small reductions in yield and purity can be provided.
    Type: Grant
    Filed: December 13, 2002
    Date of Patent: December 11, 2007
    Assignee: Aies Co., Ltd.
    Inventors: Shuji Inada, Kikuchi Sato
  • Patent number: 7202283
    Abstract: The present invention provides a dissolution method for saturated polyester capable of recycling saturated polyester used in fibers, a film, a bottle and others with ease and a low cost, a solution decomposing saturated polyester and a decomposition method using the solution.
    Type: Grant
    Filed: November 13, 2002
    Date of Patent: April 10, 2007
    Assignee: Hitachi Chemical Co., Ltd.
    Inventors: Hisayo Masuda, Katsuji Shibata, Hiroyuki Izawa, Ayako Iwamaru
  • Patent number: 7135588
    Abstract: The present invention results to an improved and environment friendly method of producing dimethyl phthalate of about 99% purity from naphthalene based chemicals, said method comprising steps of mixing phthalic anhydride with methanol in the ratio ranging between 2:3 to 3:2, adding catalyst(s) to the mixture wherein, the ratio of phthalic anhydride and the catalyst is ranging between 3:1 to 15:1, adding a promoter to the resultant of step (b) wherein, the promoter is in the range of 1.5 to 2.0% by weight of phthalic anhydride, refluxing the resulted mixture at a temperature ranging between 60 to 100° C., for time duration ranging between 6 to 12 hrs. in the presence of benzene, wherein the ratio of benzene to phthalic anhydride is in the range of 1:5 to 2:1 to obtain distillate, neutralizing the residue with about 10% caustic soda, extracting the neutralized residue with the benzene, distilling at the temperature ranging between 140 to 150° C. under 10 mm of mercury to obtain dimethyl phthalate.
    Type: Grant
    Filed: March 5, 2004
    Date of Patent: November 14, 2006
    Assignee: Council of Scientific and Industrial Research
    Inventor: Kumares Chandra Bit
  • Patent number: 7078440
    Abstract: A dimethyl terephthalate composition includes 0.001 to 200 ppm of methyl 4-(1,3-dioxolan-2-yl)benzoate and 0 to 1 ppm of dimethyl hydroxyterephthalate contained in dimethyl terephthalate, and exhibits improved properties as a material for producing polyester.
    Type: Grant
    Filed: November 22, 2001
    Date of Patent: July 18, 2006
    Assignee: Teijin Limited
    Inventors: Kenichi Ishihara, Kazumasa Mizuno, Minoru Nakashima, Kazuhiro Sato, Masanori Miyamoto, Taizo Mori
  • Patent number: 7030264
    Abstract: Bis-?-hydroxyethyl terephthalate having an optical density measured in a 10 wt % methanol solution at a measurement wavelength of 380 nm and a cell optical path length of 10 mm of 0.000 to 0.006. The present invention makes it clear that purified BHET having an optical density of 0.006 or less provides high-quality PET having excellent purity, whiteness and transparency.
    Type: Grant
    Filed: July 31, 2000
    Date of Patent: April 18, 2006
    Assignee: Aies Co. Ltd.
    Inventors: Shuji Inada, Kikuchi Sato
  • Patent number: 6867322
    Abstract: An ester-forming monomer obtained by depolymerization of polytrimethylene terephthalate and having an acrolein content of no greater than 0.5 wt %. Polymers obtained using the monomer and fibers, films and molded articles comprising the polymers. The ester-forming monomer is obtained by reacting polytrimethylene terephthalate with at least one compound selected from among monoalcohols, 1,3-propanediol and water in the presence of a basic substance. When the recovered ester-forming monomer is used as the starting material for production of a polymer, it is possible to produce a molding polymer for fibers, films and the like with quality equivalent to or higher than that obtained using virgin monomer.
    Type: Grant
    Filed: September 13, 2000
    Date of Patent: March 15, 2005
    Assignee: Asahi Kasei Kabushiki Kaisha
    Inventors: Jinichiro Kato, Katsuhiro Fujimoto
  • Publication number: 20040215035
    Abstract: The present invention results to an improved and environment friendly method of producing dimethyl phthalate of about 99% purity from naphthalene based chemicals, said method comprising steps of mixing phthalic anhydride with methanol in the ratio ranging between 2:3 to 3:2, adding catalyst(s) to the mixture wherein, the ratio of phthalic anhydride and the catalyst is ranging between 3:1 to 15:1, adding a promoter to the resultant of step (b) wherein, the promoter is in the range of 1.5 to 2.0% by weight of phthalic anhydride, refluxing the resulted mixture at a temperature ranging between 60 to 100° C., for time duration ranging between 6 to 12 hrs. in the presence of benzene, wherein the ratio of benzene phthalic anhydride is in the range of 1:5 to 2:1 to obtain distillate, neutralizing the residue with about 10% caustic soda, extracting the neutralized residue with the benzene, distilling at the temperature ranging between 140 to 150° C. under 10 mm of mercury to obtain dimethyl phthalate.
    Type: Application
    Filed: March 5, 2004
    Publication date: October 28, 2004
    Applicant: COUNCIL OF SCIENTIFIC AND INDUSTRIAL RESEARCH
    Inventor: Kumares Chandra Bit
  • Patent number: 6720448
    Abstract: The present invention relates to a method of recovering a solution comprising the chemical species obtained by depolymerization of PET from a material containing poly(ethylene terephthalate) in the form of bottles, by making said material react, in the absence of water, with a reagent consisting of one or more metal salts of a weaker acid than the terephthalic acid and of ethylene glycol, until a water-soluble intermediate product is obtained, and subsequently carrying out dissolution in water, stirring and filtering.
    Type: Grant
    Filed: October 2, 2001
    Date of Patent: April 13, 2004
    Inventor: Massimo Broccatelli
  • Patent number: 6710202
    Abstract: To provide a process for producing a high-purity bis-&bgr;-hydroxyethyl terephthalate from crude terephthalic acid.
    Type: Grant
    Filed: August 5, 2002
    Date of Patent: March 23, 2004
    Assignee: Aies Co., Ltd.
    Inventors: Shuji Inada, Kikuchi Sato
  • Patent number: 6706843
    Abstract: For separation and recovery of dimethyl terephthalate (DMT) and ethyiene glycol (EG) from polyester waste containing foreign materials, the polyester waste is treated in EG containing a polyester depolymerization catalyst, a solid foreign material fraction floated on the surface of the resultant reaction solution is removed and the residual solid foreign material fraction is removed from the remaining solution fraction. The remaining solution fraction is distilled and concentrated and the distilled EG is recovered. A transesterification reaction catalyst and methanol are mixed into the distillation residue. The resultant reaction mixture is recrystallized and subjected to centrifugal separation to separate the reaction mixture into the DMT cake and a mixture solution, and then the cake is distilled whereby high-purity DMT is recovered. The residual mixture solution is subjected to distillation treatment for recovery of the methanol, and the distillation residue is distilled to recover EG.
    Type: Grant
    Filed: April 19, 2002
    Date of Patent: March 16, 2004
    Assignee: Teijin Limited
    Inventors: Kenichi Ishihara, Kenji Ishida, Masanori Miyamoto, Minoru Nakashima, Kazuhiro Sato, Hideo Hasegawa
  • Patent number: 6630601
    Abstract: An aromatic polyester is pre-decomposed by heating together with bis-&bgr;-hydroxyethyl terephthalate and/or a low condensate thereof and then, reacted with ethylene glycol to convert the terephthalic acid component of the pre-decomposed product into bis-&bgr;-hydroxyethyl terephthalate and/or a low condensate thereof. The thus obtained solution composition, that is, bis-&bgr;-hydroxyethyl terephthalate solution composition containing ethylene glycol, bis-&bgr;-hydroxyethyl terephthalate and cations and/or anions as impurities is brought into contact with a cation exchanger and/or an anion exchanger to remove cations and anions as impurities to produce bis-&bgr;-hydroxyethyl terephthalate having a small content of ions.
    Type: Grant
    Filed: August 17, 2000
    Date of Patent: October 7, 2003
    Assignee: Aies Company Limited
    Inventors: Shuji Inada, Kikuchi Sato
  • Patent number: 6569901
    Abstract: The present invention relates to compounds of formula (I) The compounds are useful in the treatment and/or prevention of conditions mediated by nuclear receptors, in particular the Peroxisome Proliferator-Activated Receptors (PPAR).
    Type: Grant
    Filed: January 26, 2001
    Date of Patent: May 27, 2003
    Assignee: Novo Nordisk A/S
    Inventors: John Patrick Mogensen, Per Sauerberg, Paul Stanley Bury, Lone Jeppesen, Ingrid Pettersson
  • Publication number: 20030088121
    Abstract: A method for purifying crude 2,6-naphthalenedicarboxylic acid includes a reduction step of reducing crude 2,6-naphthalenedicarboxylic acid containing 6-formyl-2-naphthoic acid with hydrogen and a cleaning step of cleaning the reduction product with alcohol. Preferably, in the reduction step, the crude 2,6-naphthalenedicarboxylic acid and the hydrogen is brought into contact with a hydrogenation catalyst in a liquid phase, and particularly in water. The method makes the purification process less complex and makes it possible to produce high-purity 2,6-naphthalenedicarboxylic acid without damaging equipment or increasing cost.
    Type: Application
    Filed: July 12, 2002
    Publication date: May 8, 2003
    Applicant: Kabushiki Kaisha Kobe Seiko Sho(Kobe Steel, Ltd.)
    Inventors: Yoshiyuki Nagase, Koji Yamamoto, Takeharu Tanaka, Maki Hamaguchi
  • Patent number: 6548695
    Abstract: Provided is a process for producing an isocoumarin-3-yl-acetic acid derivative, characterized by reacting a homophthalic acid derivative represented by a formula: (wherein Rc, R2 and R are mainly protecting groups) with a malonic acid derivating represented by a formula: (wherein R is an organic group including a lower alkyl group; R3 is a protecting group for a carboxyl group; and X is a halogen atom or a —OM group (wherein M is alkaline metal or alkaline earth metal)). According to the above process, various isocoumarin-3-yl-acetic acid derivatives can efficiently be provided.
    Type: Grant
    Filed: April 11, 2002
    Date of Patent: April 15, 2003
    Assignees: Mercian Corporation, Zaidan Hojin Biseibutsu Kagaku Kenkyu Kai
    Inventors: Toshio Tsuchida, Hazuki Nagai, Takashi Nakashima, Masashi Yoshida, Kaname Konuki, Asako Kuroda, Kunio Isshiki, Tomio Takeuchi
  • Patent number: 6534677
    Abstract: The present invention provides a carbon-containing catalyst support that includes at least a carbonaceous material nd a thermosetting or sinterable polymer. The components are mixed and the polymer sintered or thermoset to provide a non-crushable, non-friable, and non-breakable composite. A catalytically active metal can be supported on the carbonaceous material prior to mixing, or on the composite after mixing and heating the mixture to sinter or thermoset the polymer.
    Type: Grant
    Filed: June 4, 2001
    Date of Patent: March 18, 2003
    Assignee: Engelhard Corporation
    Inventors: James Ferguson White, Jeffrey James Ramler
  • Patent number: 6509507
    Abstract: A process for preparing polymerizable biaryl derivatives comprises reacting an aromatic comprising a 6-membered ring which bears ester or benzylic OH groups in the 1,4 position with a second aromatic in a palladium-catalyzed cross-coupling reaction to give a biaryl and converting the ester or benzylic OH groups into polymerizable groups in one or more steps. The biaryls obtained are suitable for preparing polymers which are used as electroluminescence materials.
    Type: Grant
    Filed: October 16, 2001
    Date of Patent: January 21, 2003
    Assignee: Aventis Research & Technologies GmbH & Co. KG
    Inventors: Hubert Spreitzer, Willi Kreuder, Heinrich Becker, Jochen Krause
  • Publication number: 20020173674
    Abstract: This invention provides a process for purifying the crude aromatic dicarboxylic acids produced by oxidation of dialkyl aromatic hydrocarbons and for using the purified acids in the preparation of polyethylene terephthalate, polyethylene naphthalate and other polyesters. The invention simplifies the manufacturing process by converting the crude aromatic acids into bis-glycol esters in an esterification reactor 4, from which the esterified partial oxidation impurities present in the oxidation product are removed by distillation in distillation tower 5. After removal of the volatile impurities, the dicarboxylic acid esters can separated by distillation in distillation tower 6 or by crystallization and converted to polyesters by polycondensation. The volatile impurities reoved as overhead from tower 5 can be recycled as stream 16 to the oxidation reactor where they act as oxidation promoters thereby optionally allowing for a bromine-free oxidation process for dialkyl aromatic hydrocarbons.
    Type: Application
    Filed: April 26, 2002
    Publication date: November 21, 2002
    Inventors: Krishna Kulai Rao, Russell D. Sellen, Xiaobing Feng, James Spanswick, William F. Huber
  • Publication number: 20020173673
    Abstract: This invention provides a process for purifying the crude aromatic dicarboxylic acids produced by oxidation of dialkyl aromatic hydrocarbons and for using the purified acids in the preparation of polyethylene terephthalate, polyethylene naphthalate and other polyesters. The invention simplifies the manufacturing process by converting the crude aromatic acids into bis-glycol esters in an esterification reactor 4, from which the esterified partial oxidation impurities present in the oxidation product are removed by distillation in distillation tower 5. After removal of the volatile impurities, the dicarboxylic acid esters can separated by distillation in distillation tower 6 or by crystallization and converted to polyesters by polycondensation. The volatile impurities reoved as overhead from tower 5 can be recycled as stream 16 to the oxidation reactor where they act as oxidation promoters thereby optionally allowing for a bromine-free oxidation process for dialkyl aromatic hydrocarbons.
    Type: Application
    Filed: May 18, 2001
    Publication date: November 21, 2002
    Inventors: Krishna Kulai Rao, Russell D. Sellen, Xiaobing Feng
  • Patent number: 6472557
    Abstract: A process for producing high quality TPA suitable for PET feedstock material from recycled polyester. The process includes the steps of depolymerizing the polyester to form DMT; separating the DMT from secondary materials; and hydrolyzing the DMT to form TPA. In a preferred embodiment of the invention the recycled polyester is contacted with a component monomer or oligomer thereof to liquefy the polyester prior to depolymerizing the polyester.
    Type: Grant
    Filed: November 12, 1999
    Date of Patent: October 29, 2002
    Assignee: Eastman Chemical Company
    Inventors: Thomas Michael Pell, Jr., Michael Paul Ekart, David Dunlap Cornell, Damon Brian Shackelford, Donald Lee Carver
  • Patent number: 6369263
    Abstract: A hydroquinone diester derivative represented by the formula (1): wherein R1 and R2 are the same or different, each representing an alkyl group, a cycloalkyl group, an aryl group, or a heterocyclic group is crystallized from a reaction mixture containing the hydroquinone diester derivative, and the resulting product in crystallized form is washed. A solvent for the crystallization is composed of an organic carboxylic acid and water, and the crystallized product is washed with warm or hot water of 40° C. or above. In the formula (1), R1 and R2 are C1-4alkyl groups.
    Type: Grant
    Filed: August 28, 2000
    Date of Patent: April 9, 2002
    Assignee: Daicel Chemical Industries, Ltd.
    Inventor: Tomohide Ina
  • Patent number: 6310235
    Abstract: The invention relates to an improved method for producing ester plasticizers by reacting di- or polycarboxylic acids or their anhydrides with alcohols in the presence of metal catalysts.
    Type: Grant
    Filed: November 17, 1999
    Date of Patent: October 30, 2001
    Assignee: Celanese GmbH
    Inventor: Wilhelm Gick
  • Patent number: 6262294
    Abstract: This invention relates to a process for producing aromatic divalent carboxylic acid ester and diatomic alcohol by reacting aromatic polyester and super critical monatomic alcohol, and by the process, PET is decomposed for recovering monomer components therefrom, and thus recovered monomer components can be used as the material for reproduction of new PET. In accordance with the present invention, there is provided a process for producing continuously monomer components from aromatic polyester, the process including the steps of: feeding continuously the above aromatic polyester and the above monatomic alcohol into a reactor while the above reactor is kept to be under the super critical condition of the above monatomic alcohol; reacting the above aromatic polyester and the above super critical monatomic alcohol and discharging the resultant reaction products, i.e.
    Type: Grant
    Filed: February 16, 2000
    Date of Patent: July 17, 2001
    Assignees: Agency of Industrial Science and Technology, Shin Nippon Air Technologies Co., Ltd.
    Inventors: Takeshi Sako, Masazumi Godo, Seiji Ishida, Kunio Miura, Masayuki Tsugumi
  • Patent number: 6211398
    Abstract: Disclosed is a process for the production and purification of dialkyl naphthalenedicarboxylate compounds wherein a crude naphthalenediacarboxylic acid is esterified with an alkanol such as methanol to produce a crude esterification product comprising dialkyl naphthalenedicarboxylate, starting materials and other compounds and the crude esterification product is purified by flash distillation to remove impurities which can cause fouling of conventional distillation equipment. A particularly useful diester is dimethyl 2,6-naphthalenedicarboxylate.
    Type: Grant
    Filed: September 9, 1998
    Date of Patent: April 3, 2001
    Assignee: Eastman Chemical Company
    Inventor: Thomas Michael Pell, Jr.
  • Patent number: 6180817
    Abstract: A process for preparing crude dimethyl terephthalate, comprises oxidizing a mixture comprising para-xylene and methyl para-toluate, esterifying the oxidized mixture with methanol, separating the resulting crude ester into fractions. By separating the crude ester with a distillation column containing structured packing and using a lower bottom temperature, product yield is increased, and the process is made more economical.
    Type: Grant
    Filed: September 16, 1998
    Date of Patent: January 30, 2001
    Assignee: Huels Aktiengesellschaft
    Inventors: Udo Lenz, Ulrich Neutzler, Anton Schoengen, Reinhard Sigg
  • Patent number: 6150552
    Abstract: Provided are methods for the preparation and purification of alkyl tetrahalophthalate esters by the reaction of a tetrahalophthalic compound with an alkanol in the presence of a titanate catalyst. More particularly, improved methods are provided for making and recovering an ester with little contamination by catalytic metal components and color bodies, and with little acidity, in a high yield from the esterification reaction by pretreating the starting materials to reduce the acidity thereof, reacting the starting materials in the presence of a titanate catalyst, stripping excess alcohol, hydrolyzing the catalyst, and filtering out solids to yield a high purity tetrahalophthalate ester product.
    Type: Grant
    Filed: June 30, 1999
    Date of Patent: November 21, 2000
    Assignee: Great Lakes Chemical Corporation
    Inventors: Jeffrey A. Schreier, James D. Siebecker, Arthur G. Mack
  • Patent number: 6136869
    Abstract: A process for recovering suitable polyester feedstock material from recycled polyester includes the steps of depolymerizing the polyester into its component ester monomers and half-esters; separating the monomers and half-esters from other secondary materials; and mixing the component ester monomers and half-esters with additional monomers to produce a low molecular weight polyester. In a preferred embodiment of the invention the recycled polyester is contacted with a component monomer or oligomer thereof to liquefy the polyester before the polyester is depolymerized.The invention further provides an apparatus for carrying out the process. The apparatus includes a first reactor for depolymerizing the recycled polyester, a separator for separating ester monomeric components and half-esters from secondary materials produced in the first reactor, and a second reactor for producing a low molecular weight polyester from the liquefied separator products.
    Type: Grant
    Filed: October 6, 1998
    Date of Patent: October 24, 2000
    Assignee: Eastman Chemical Company
    Inventors: Michael Paul Ekart, Thomas Michael Pell, Jr., David Dunlap Cornell, Damon Bryan Shackelford
  • Patent number: 6096171
    Abstract: A process for purifying a crude ester containing dimethyl terephthalate, includes flash distilling a mixture including para-xylene and methyl para-toluate, and separating the crude ester into fractions. By separating the crude ester with a distillation column containing structured packing and using a lower bottom temperature, product yield is increased, and the process is made more economical.
    Type: Grant
    Filed: May 13, 1998
    Date of Patent: August 1, 2000
    Assignee: Huels Aktiengesellschaft
    Inventors: Udo Lenz, Ulrich Neutzler, Anton Schoengen, Reinhard Sigg
  • Patent number: 6013831
    Abstract: A process for the production of high-purity dimethyl 2,6-naphthalenedicarboxylate, which comprises esterifying 2,6-naphthalenedicarboxylic acid obtained by liquid phase oxidation of 2,6-dialkylnaphthalene with molecular oxygen in the presence of an oxidation catalyst, with methanol and then purifying a crude ester formed by the esterification, the crude ester being purified in the presence of an aromatic hydrocarbon as a solvent, in which impurities contained in a reaction product obtained by the esterification of 2,6-naphthalenedicarboxylic acid prepared by the liquid phase oxidation of 2,6-dialkylnaphthalene are effectively removed with simple procedures, oxidation catalyst metals are recovered, a crystal of naphthalenedicarboxylic acid formed by the oxidation of dialkylnaphthalene and/or its oxide derivative can be easily separated, and the oxidation catalyst to be brought into the step of producing dimethyl naphthalenedicarboxylate is recovered in the process of the production of naphthalenedicarboxylic a
    Type: Grant
    Filed: April 30, 1998
    Date of Patent: January 11, 2000
    Assignee: Mitsubishi Gas Chemical Company, Inc.
    Inventors: Hiroshi Machida, Fumiya Zaima, Kengi Nakaya, Kazuo Tanaka
  • 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
  • Patent number: 5948934
    Abstract: A process is disclosed for recycling of polyester used in the fabrication of molded plastic goods, such as films, carbonated beverage bottles and particularly waste poly(ethylene terephthalate) (PET) bottle grade, manufacturing residues and other manufactured articles. The process comprises the alcoholysis of washed or cleaned, crushed or grinded PET in one step of reaction, with alcohols containing from 1 to 4 carbon atoms in their molecule, in an autoclave reactor capable to support pressures of about 10 MPa (100 Kg/cm.sup.2 gage) and operating temperatures in the range of 10 to 300.degree. C.; followed by one or several steps of reaction product purification such as crystallization and/or centrifugation and/or distillation. The alcoholysis reaction product is a dialkyl aromatic ester (DAAE), which is recovered by filtration or centrifugation and depending on the alcohol used in the process the DAAE obtained are several industrial products such as dimethyl terephthalate, dibutyl terephthalate, etc.
    Type: Grant
    Filed: January 2, 1998
    Date of Patent: September 7, 1999
    Assignee: Resinas y Materiales
    Inventors: M.-Javier Cruz-Gomez, Cecilia Rodriguez-Martinez, Nicolas Ramirez-de-Arellano-Aburto
  • Patent number: 5880310
    Abstract: Provided is a process for producing a plasticizer ester characterized by previously removing dissolved oxygen in a starting alcohol, and then subjecting an organic acid or its anhydride and the alcohol to an esterification reaction in the presence of an organic metal compound catalyst, which process can substantially reduce formation of coloring impurities and can easily provide a plasticizer ester having a low degree of coloring.Further, a plasticizer ester having a high volume resistivity can easily be obtained by adding an alkaline aqueous solution to a reaction product obtained by an esterification reaction to conduct neutralization of an unreacted acid and hydrolysis of the catalyst, further blowing a carbon dioxide gas to convert the residual alkali into a carbonate, recovering an excess alcohol, and then conducting purification through finefiltration using a filter aid or further in combination with adsorption treatment.
    Type: Grant
    Filed: April 23, 1998
    Date of Patent: March 9, 1999
    Assignee: Mitsubishi Gas Chemical Company, Inc.
    Inventors: Kuniaki Ageishi, Tadayoshi Takefumi, Tsutomu Numoto, Tsuguji Kawabata, Etsuo Urabe
  • Patent number: 5852201
    Abstract: A process for preparing crude dimethyl terephthalate, comprises oxidizing a mixture comprising para-xylene and methyl para-toluate, esterifying the oxidized mixture with methanol, separating the resulting crude ester into fractions. By separating the crude ester with a distillation column containing structured packing and using a lower bottom temperature, product yield is increased, and the process is made more economical.
    Type: Grant
    Filed: January 17, 1997
    Date of Patent: December 22, 1998
    Assignee: Huels Aktiengesellschaft
    Inventors: Udo Lenz, Ulrich Neutzler, Anton Schoengen, Reinhard Sigg
  • Patent number: 5821381
    Abstract: There is described a process for depolymerizing polyesters such as polyethylene terephthalate polyester to monomer components comprising esters such as dimethyl terephthalate and purifying the ester by sublimation, which purified ester can then be used to make virgin polyester.
    Type: Grant
    Filed: February 3, 1997
    Date of Patent: October 13, 1998
    Assignee: Eastman Kodak Company
    Inventor: Andrius A. Naujokas
  • Patent number: 5801269
    Abstract: Processes for recovering 4,4'-dimethyl bibenzoate (DMBB) from byproduct streams of dimethyl terephthalate (DMT) production are disclosed. The byproduct streams are treated to produce an overhead stream which includes DMBB. In one aspect of the invention, the overhead product stream is added to an organic solvent under conditions sufficient to rapidly form a suspension of crystallized DMBB. In another aspect of the invention, the overhead is dissolved in an appropriate organic solvent and cooled to form a suspension of DMBB crystals in the solvent. A portion of the suspension is removed, and the remaining portion of the suspension centrifuged to recover DMBB crystals. In still another aspect of the invention, the overhead stream is treated with an organic solvent to form a slurry of DMBB crystals, and the resultant slurry thermally treated to increase the concentration of DMBB crystals therein while also solubilizing any organic contaminants.
    Type: Grant
    Filed: April 30, 1997
    Date of Patent: September 1, 1998
    Assignee: Hoechst Celanese Corp.
    Inventors: Carrie A. Feeney, Ida L. Jones, Bennett C. Ward, Thomas M. Kenesson, Charles B. Hilton, Michael R. Ahern, Gregory M. Adams, Edward M. de la Garza, B. Frank Wood, Jr., Thomas L. Grantland, Kan J. Tsai, James L. Ragan