Patents by Inventor Ralf Wirges

Ralf Wirges 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).

  • Process for the production of DMT-intermediate product of specific purity and pure terephthalic acid
    Patent number: 5338882
    Abstract: The invention relates to a process for the production of a DMT intermediate product as well as its working up to fibregrade DMT and to medium pure and pure terephthalic acid.
    Type: Grant
    Filed: November 4, 1993
    Date of Patent: August 16, 1994
    Assignee: Huls Aktiengesellschaft
    Inventors: Hermann-Josef Korte, Anton Miletic, Hans U. Neutzler, Anton Schoengen, Johann H. Schroeder, Ralf Wirges
  • Process for the production of DMT-intermediate product of specific purity
    Patent number: 5286896
    Abstract: The invention relates to a process for the production of a DMT intermediate product as well as its working up to fibregrade DMT and to medium pure and pure terephthalic acid.
    Type: Grant
    Filed: August 15, 1991
    Date of Patent: February 15, 1994
    Assignee: Huls Aktiengesellschaft
    Inventors: Hermann-Josef Korte, Anton Miletic, Hans U. Neutzler, Anton Schoengen, Johann H. Schroeder, Ralf Wirges
  • Process for producing terephthalic acid from p-xylene and methanol by way of dimethyl terephthalate
    Patent number: 4642377
    Abstract: A process for the production of terephthalic acid from p-xylene and methanol by way of the dimethyl terephthalate obtained by oxidation, in the liquid phase with atmospheric oxygen in the presence of dissolved heavy metal compounds as the catalyst, of a mixture of p-xylene and a fraction containing predominantly methyl p-toluate, which fraction is recycled into the oxidation, to obtain an oxidation product containing primarily p-toluic acid and monomethyl terephthalate at a temperature of 140.degree.-170.degree. C. and under a pressure of 4-8 bar; by esterification of the oxidation product in a reactor with liquid and subsequently vaporized methanol brought to an elevated pressure, at a temperature of 220.degree.-280.degree. C.
    Type: Grant
    Filed: March 4, 1985
    Date of Patent: February 10, 1987
    Assignee: Dynamit Nobel Aktiengesellschaft
    Inventors: Rudolf Modic, Jorg Porschen, Anton Schoengen, Ralf Wirges
  • Process for the production of dimethyl terephthalate from p-xylene and methanol
    Patent number: 4642369
    Abstract: A process for the production of dimethyl terephthalate from p-xylene and methanol by oxidation in a reactor, in the liquid phase with atmospheric oxygen in the presence of dissolved heavy metal compounds as a catalyst, of a mixture of p-xylene and a fraction containing predominantly methyl p-toluate, which fraction is recycled into the oxidation, to obtain an oxidation product containing primarily p-toluic acid and monomethyl terephthalate, at a temperature of 140.degree.-170.degree. C. and under a pressure of 4-8 bar; by esterification of the oxidation product with liquid and subsequently vaporized methanol brought to an elevated pressure, at a temperature of 220.degree.-280.degree. C.
    Type: Grant
    Filed: March 4, 1985
    Date of Patent: February 10, 1987
    Assignee: Dynamit Nobel Aktiengesellschaft
    Inventors: Rudolf Modic, Jorg Porschen, Anton Schoengen, Ralf Wirges