Patents by Inventor Takashi Murakawa

Takashi Murakawa 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).

  • Patent number: 5260238
    Abstract: There is disclosed a process for regenerating a deactivated catalyst containing a zeolite and a noble metal of group VIII of the Periodic Table supported thereon which comprises subjecting the deactivated catalyst to decoking treatment under reductive or oxidative condition and subsequently to contact treatment with a solution containing a halogen or a halogen-containing compound and thereafter calcining the deactivated catalyst. According to the above process, the catalytic activity of a deactivated catalyst is restored to the level comparable to that of a fresh catalyst by the use of an inexpensive regenerating agent and simplified steps. Thus, the regeneration process is expected to find effective use in petroleum refinery, petrochemical industry, etc.
    Type: Grant
    Filed: September 25, 1992
    Date of Patent: November 9, 1993
    Assignee: Idemitsu Kosan Co., Ltd.
    Inventors: Takashi Murakawa, Michio Sugimoto
  • Patent number: 5196631
    Abstract: The catalyst is an L-type zeolite with platinum supported thereon, which is then treated with a halogen-containing compound. The catalyst has a long catalyst life and is extremely useful for the preparation of aromatic hydrocarbons from aliphatic hydrocarbons. The process using the catalyst provides a production of aromatic hydrocarbons with a high yield.
    Type: Grant
    Filed: November 15, 1991
    Date of Patent: March 23, 1993
    Assignee: Research Association for Utilization of Light Oil
    Inventors: Takashi Murakawa, Hisashi Katsuno
  • Patent number: 5091351
    Abstract: The catalyst is an L-type zeolite with platinum supported thereon, which is then treated with a halogen-containing compound. The catalyst has a long catalyst life and is extremely useful for the preparation of aromatic hydrocarbons from aliphatic hydrocarbons. The process using the catalyst provides a production of aromatic hydrocarbons with a high yield.
    Type: Grant
    Filed: April 21, 1989
    Date of Patent: February 25, 1992
    Assignee: Research Association for Utilization of Light Oil
    Inventors: Takashi Murakawa, Hisashi Katsuno
  • Patent number: 4962251
    Abstract: A process for producing aromatic hydrocarbons in a high yield by introducing a naphtha fraction the cyclopentane content of which is controlled to not more than 1% by weight, or the methylpentane content is controlled to not more than 10% by weight, in a catalytic reaction tower, and contacting with a catalyst comprising a large pore zeolite containing at least one of Group VII metals of the Periodic Table. In this process, the catalyst cycle is greatly lengthened.
    Type: Grant
    Filed: December 28, 1989
    Date of Patent: October 9, 1990
    Assignee: Research Association for Utilization of Light Oil
    Inventors: Takashi Yamamoto, Toshikazu Yoneda, Hisashi Katsuno, Takashi Murakawa, Nobuyuki Takahashi
  • Patent number: 4937215
    Abstract: A process for restoring deactivated catalysts containing zeolite with a noble metal of Group VIII of the Periodic Table and to be used in the production of aromatic compounds, wherein decoking of the deactivated catalysts is carried out in the presence of halogen or a halogen-containing compound. This restoration process permits effective restoration of deactivated catalysts and thus is expected to be employed in the fields of petroleum purification, petrochemistry and so forth.
    Type: Grant
    Filed: October 12, 1988
    Date of Patent: June 26, 1990
    Assignee: Research Association for Utilization of Light Oil
    Inventors: Takashi Murakawa, Tomoaki Hirano
  • Patent number: 4761512
    Abstract: A process for producing aromatic hydrocarbons which comprises contacting at least one type of hydrocarbon selected from paraffin, olefin, acetylene, cyclic paraffin and cyclic olefin-based hydrocarbons with a catalyst comprising a L-type zeolite treated with a halogen-containing compound and platinum deposited thereon.
    Type: Grant
    Filed: March 31, 1987
    Date of Patent: August 2, 1988
    Assignee: Research Association for Utilization of Light Oil
    Inventors: Hisashi Katsuno, Takashi Murakawa, Toshikazu Yoneda
  • Patent number: 4681865
    Abstract: A catalyst for production of aromatic hydrocarbons and a process for producing aromatic hydrocarbons from various hydrocarbons using said catalyst are disclosed. The catalyst comprises a L-type zeolite treated with a halogen-containing compound and platinum deposited thereon, which is of high activity and then has a long service life. The process of the present invention using the catalyst enables to produce aromatic hydrocarbons in a yield as high as not less than 80% for a long time. The hydrocarbon feedstock is selected from paraffin, olefin, acetylene, cyclic paraffin, and cyclic olefin-based hydrocarbons.
    Type: Grant
    Filed: April 28, 1986
    Date of Patent: July 21, 1987
    Assignee: Research Association For Utilization of Light Oil
    Inventors: Hisashi Katsuno, Takashi Murakawa, Toshikazu Yoneda