Patents by Inventor Belaid AIT AISSA

Belaid AIT AISSA 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: 20230096748
    Abstract: A process for producing alkyl methacrylates, in particular methyl methacrylate (MMA), includes production of methacrolein (MAL) in a first reaction stage; direct oxidative esterification (DOE) of the methacrolein with an alcohol, preferably methanol, to afford an alkyl methacrylate in a second reaction stage: and workup of the alkyl methacrylate crude product from the second reaction stage. An optimized workup of the reactor output from the oxidative esterification of methacrolein involves minimizing the amount of employed water, the amount of employed acid, and/or the amount of aqueous waste streams, through an optimized recycling of the generated process water streams.
    Type: Application
    Filed: November 23, 2022
    Publication date: March 30, 2023
    Applicant: Röhm GmbH
    Inventors: Florian ZSCHUNKE, Belaid Ait Aissa, Andreas Rühling, Gerhard Kölbl, Steffen Krill, Daniel Helmut König
  • Patent number: 11560350
    Abstract: A process for producing alkyl methacrylates, in particular methyl methacrylate (MMA), includes production of methacrolein (MAL) in a first reaction stage; direct oxidative esterification (DOE) of the methacrolein with an alcohol, preferably methanol, to afford an alkyl methacrylate in a second reaction stage; and workup of the alkyl methacrylate crude product from the second reaction stage. An optimized workup of the reactor output from the oxidative esterification of methacrolein involves minimizing the amount of employed water, the amount of employed acid, and/or the amount of aqueous waste streams, through an optimized recycling of the generated process water streams.
    Type: Grant
    Filed: September 15, 2020
    Date of Patent: January 24, 2023
    Assignee: Röhm GmbH
    Inventors: Florian Zschunke, Belaid Ait Aissa, Andreas Rühling, Gerhard Kölbl, Steffen Krill, Daniel Helmut König
  • Publication number: 20220388942
    Abstract: A novel process can be used for purifying methyl methacrylate (MMA) contaminated with low-boiling components by distillation, where the process involves producing MMA by oxidative esterification, and a crude product containing methyl propionate (MP), methyl isobutyrate (MIB), and methacrolein (MAL) as low-boiling components. The process is compatible with MMA produced from C2-based methacrolein containing the low-boiling components specified.
    Type: Application
    Filed: September 10, 2020
    Publication date: December 8, 2022
    Applicant: Röhm GmbH
    Inventors: Steffen Krill, Daniel Helmut König, Belaid Ait Aissa
  • Publication number: 20220388941
    Abstract: A novel process can be used for a heterogeneously catalysed oxidation reaction, in the presence of a pulverulent noble metal-containing catalyst, where (meth)acrolein, an alkyl alcohol, in particular methanol, and an oxygen-containing gas are converted to an alkyl (meth)acrylate, in particular methyl (meth)acrylate. A corresponding reactor suitable for performing the reaction is also useful. The process allows for an effective retention of the particulate catalyst and the continuous discharge of fines fractions of the catalyst powder which are present, particularly in a fresh catalyst batch as a consequence of its preparation. Such fines fractions may also be produced by abrasion during the reaction. The process allows for effective recycling, recovery, and utilization of these discharged catalyst fractions.
    Type: Application
    Filed: May 25, 2022
    Publication date: December 8, 2022
    Applicant: Röhm GmbH
    Inventors: Steffen KRILL, Belaid Ait Aissa, Andreas Rühling, Mounir Stitou, Andreas Gräff, Olaf Merker
  • Publication number: 20220380293
    Abstract: A process produces methyl methacrylate by direct oxidative esterification of methacrolein. Methyl methacrylate is used in large amounts for producing polymers and copolymers with other polymerizable compounds. An optimized workup of the reactor discharge from the oxidative esterification of methacrolein allows for co-discharged fine catalyst particles to be very efficiently separated and optionally removed or recycled. In addition, this process can reduce the formation of byproducts in extended continuous operation compared to known variant. A reactor system contains stirrer configurations which allow virtually abrasion-free operation and thus a catalyst on-stream time of several years.
    Type: Application
    Filed: May 25, 2022
    Publication date: December 1, 2022
    Applicant: Röhm GmbH
    Inventors: Steffen KRILL, Andreas Rühling, Belaid Ait Aissa
  • Publication number: 20220356282
    Abstract: A process can be used for producing optical molding materials on the basis of methyl methacrylate (MMA). The MMA produced by an optimized method and the molding materials feature in particular a very low yellowness index. This MMA has been produced by direct oxidative esterification of methacrolein. An optimized workup of the reactor output from the oxidative esterification of methacrolein can be used for removing particularly discoloring byproducts. This process moreover has the advantage that fewer demands are placed on plant apparatus configuration.
    Type: Application
    Filed: July 22, 2022
    Publication date: November 10, 2022
    Applicant: Röhm GmbH
    Inventors: Steffen KRILL, Belaid Ait Aissa, Florian Zschunke, Gerhard Kõlbl, Rüdiger Carloff
  • Publication number: 20220332674
    Abstract: A process for producing alkyl methacrylates, in particular methyl methacrylate (MMA), includes production of methacrolein (MAL) in a first reaction stage; direct oxidative esterification (DOE) of the methacrolein with an alcohol, preferably methanol, to afford an alkyl methacrylate in a second reaction stage; and workup of the alkyl methacrylate crude product from the second reaction stage. An optimized workup of the reactor output from the oxidative esterification of methacrolein involves minimizing the amount of employed water, the amount of employed acid, and/or the amount of aqueous waste streams, through an optimized recycling of the generated process water streams.
    Type: Application
    Filed: September 15, 2020
    Publication date: October 20, 2022
    Applicant: Röhm GmbH
    Inventors: Florian Zschunke, Belaid Ait Aissa, Andreas Rühling, Gerhard Kölbl, Steffen Krill, Daniel Helmut König
  • Patent number: 11427664
    Abstract: A process is useful for producing optical molding materials on the basis of methyl methacrylate (MMA), wherein this MMA has been produced by an optimized method and the molding materials feature in particular a very low yellowness index. This MMA has been produced by direct oxidative esterification of methacrolein. In particular, an optimized workup of the reactor output from the oxidative esterification of methacrolein is useful for removing particularly discoloring byproducts. This process moreover has the advantage that fewer demands than described in related art are placed on plant apparatus configuration.
    Type: Grant
    Filed: August 20, 2018
    Date of Patent: August 30, 2022
    Assignee: Röhm GmbH
    Inventors: Steffen Krill, Belaid Ait Aissa, Florian Zschunke, Gerhard Kölbl, Rüdiger Carloff
  • Patent number: 11299449
    Abstract: A process for preparing methyl methacrylate by direct oxidative esterification of methacrolein has elevated yields compared to known processes. Methyl methacrylate (MMA) is used in large amounts for preparing polymers and copolymers with other polymerizable compounds. In addition, methyl methacrylate is an important synthesis unit for a variety of specialty esters based on methacrylic acid (MAA), which can be produced by transesterification with the appropriate alcohol. There is consequently a great interest in very simple, economic, and environmentally friendly processes for preparing methyl methacrylate. A superior workup of the reactor output from the oxidative esterification of methacrolein allows specific by-products to be isolated and then additionally converted to alkyl methacrylates, especially to MMA.
    Type: Grant
    Filed: June 7, 2019
    Date of Patent: April 12, 2022
    Assignee: Röhm GmbH
    Inventors: Steffen Krill, Florian Zschunke, Belaid Ait Aissa, Marcel Treskow
  • Patent number: 11124471
    Abstract: The present invention relates to a novel process for performing a heterogeneously catalyzed reaction for oxidative esterification of aldehydes to give carboxylic esters. Against this background, it has been possible by the present process according to the invention to perform such processes for longer periods without disruption, with constant or even increased activities and selectivities. This gives rise to the possibility of performing such processes in a very simple, economically viable and environmentally benign manner.
    Type: Grant
    Filed: April 23, 2018
    Date of Patent: September 21, 2021
    Assignee: Roehm GmbH
    Inventors: Alexander Lygin, Steffen Krill, Belaid Ait Aissa, Florian Zschunke
  • Publication number: 20210269385
    Abstract: A process for preparing methyl methacrylate by direct oxidative esterification of methacrolein has elevated yields compared to known processes. Methyl methacrylate (MMA) is used in large amounts for preparing polymers and copolymers with other polymerizable compounds. In addition, methyl methacrylate is an important synthesis unit for a variety of specialty esters based on methacrylic acid (MAA), which can be produced by transesterification with the appropriate alcohol. There is consequently a great interest in very simple, economic, and environmentally friendly processes for preparing methyl methacrylate. A superior workup of the reactor output from the oxidative esterification of methacrolein allows specific by-products to be isolated and then additionally converted to alkyl methacrylates, especially to MMA.
    Type: Application
    Filed: June 7, 2019
    Publication date: September 2, 2021
    Applicant: Röhm GmbH
    Inventors: Steffen Krill, Florian Zschunke, Belaid Ait Aissa, Marcel Treskow
  • Publication number: 20210047259
    Abstract: The present invention relates to a novel process for performing a heterogeneously catalyzed reaction for oxidative esterification of aldehydes to give carboxylic esters. Against this background, it has been possible by the present process according to the invention to perform such processes for longer periods without disruption, with constant or even increased activities and selectivities. This gives rise to the possibility of performing such processes in a very simple, economically viable and environmentally benign manner.
    Type: Application
    Filed: April 23, 2018
    Publication date: February 18, 2021
    Applicant: Roehm GmbH
    Inventors: Alexander LYGIN, Steffen KRILL, Belaid AIT AISSA, Florian ZSCHUNKE
  • Publication number: 20210032386
    Abstract: A process is useful for producing optical molding materials on the basis of methyl methacrylate (MMA), wherein this MMA has been produced by an optimized method and the molding materials feature in particular a very low yellowness index. This MMA has been produced by direct oxidative esterification of methacrolein. In particular, an optimized workup of the reactor output from the oxidative esterification of methacrolein is useful for removing particularly discoloring byproducts. This process moreover has the advantage that fewer demands than described in related art are placed on plant apparatus configuration.
    Type: Application
    Filed: August 20, 2018
    Publication date: February 4, 2021
    Applicant: Röhm GmbH
    Inventors: Steffen Krill, Belaid Ait Aissa, Florian Zschunke, Gerhard Kölbl, Rüdiger Carloff
  • Patent number: 10227284
    Abstract: The present invention relates to a process for preparing alpha-hydroxycarboxylic esters proceeding from hydrogen cyanide, wherein the ammonia formed in the step of alcoholysis of the corresponding alpha-hydroxycarboxamide is recycled into a hydrogen cyanide preparation process after a purification step.
    Type: Grant
    Filed: September 4, 2015
    Date of Patent: March 12, 2019
    Assignee: Evonik Roehm GmbH
    Inventors: Steffen Krill, Belaid Ait Aissa, Alexander May, Marcel Treskow
  • Patent number: 10160713
    Abstract: The present invention describes a process for dehydrating alpha-substituted carboxylic acids in the presence of water at high pressures while avoiding by-products.
    Type: Grant
    Filed: June 24, 2015
    Date of Patent: December 25, 2018
    Assignee: Evonik Roehm GmbH
    Inventors: Belaid Ait Aissa, Steffen Krill, Matthias Groemping
  • Publication number: 20180118650
    Abstract: The present invention describes a process for dehydrating alpha-substituted carboxylic acids in the presence of water at high pressures while avoiding by-products.
    Type: Application
    Filed: June 24, 2015
    Publication date: May 3, 2018
    Applicant: EVONIK ROEHM GmbH
    Inventors: Belaid AIT AISSA, Steffen KRILL, Matthias GROMPING
  • Patent number: 9809530
    Abstract: The present invention relates to a process for preparing alpha-hydroxycarboxylic esters from the alcoholysis of alpha-hydroxycarboxamides in the gas phase, characterized in that the conversion is effected in the presence of water.
    Type: Grant
    Filed: July 23, 2015
    Date of Patent: November 7, 2017
    Assignee: Evonik Roehm GmbH
    Inventors: Steffen Krill, Belaid Ait Aissa, Alexander May, Matthias Groemping
  • Publication number: 20170283364
    Abstract: The present invention relates to a process for preparing alpha-hydroxycarboxylic esters proceeding from hydrogen cyanide, wherein the ammonia formed in the step of alcoholysis of the corresponding alpha-hydroxycarboxamide is recycled into a hydrogen cyanide preparation process after a purification step.
    Type: Application
    Filed: September 4, 2015
    Publication date: October 5, 2017
    Applicant: Evonik Roehm GmbH
    Inventors: Steffen KRILL, Belaid AIT AISSA, Alexander MAY, Marcel TRESKOW
  • Publication number: 20170144960
    Abstract: The present invention relates to a process for preparing alpha-hydroxycarboxylic esters from the alcoholysis of alpha-hydroxycarboxam ides in the gas phase, characterized in that the conversion is effected in the presence of water.
    Type: Application
    Filed: July 23, 2015
    Publication date: May 25, 2017
    Applicant: Evonik Roehm GmbH
    Inventors: Steffen KRILL, Belaid AIT AISSA, Alexander MAY, Matthias GROEMPING