Patents by Inventor Kuniaki Arasuna

Kuniaki Arasuna 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).

  • Method for producing xylylenediamine
    Patent number: 9024070
    Abstract: Provided is a method for stably and economically producing xylylenediamine with a high yield and long catalyst service life by hydrogenating dicyanobenzene that is obtained by ammoxidating xylene. By bringing an aqueous basic solution into contact with a dicyanobenzene-absorbed liquid, which is obtained by bringing an ammoxidation reaction gas into contact with an organic solvent, under specified temperature conditions, and subjecting a base and a carboxylic acid in the dicyanobenzene-absorbed liquid to a neutralization reaction so as to form an aqueous phase that contains a water-soluble salt, and then subjecting an organic phase and the aqueous phase to liquid-liquid separation so as to remove the aqueous phase, it is possible to remove the carboxylic acid contained in the dicyanobenzene-absorbed liquid with high selectivity while inhibiting loss of the dicyanobenzene.
    Type: Grant
    Filed: January 30, 2012
    Date of Patent: May 5, 2015
    Assignee: Mitsubishi Gas Chemical Company, Inc.
    Inventors: Tatsuyuki Kumano, Yukiya Ibi, Kuniaki Arasuna, Shinichi Nagao
  • METHOD FOR PRODUCING XYLYLENEDIAMINE
    Publication number: 20130296609
    Abstract: Provided is a method for stably and economically producing xylylenediamine with a high yield and long catalyst service life by hydrogenating dicyanobenzene that is obtained by ammoxidating xylene. By bringing an aqueous basic solution into contact with a dicyanobenzene-absorbed liquid, which is obtained by bringing an ammoxidation reaction gas into contact with an organic solvent, under specified temperature conditions, and subjecting a base and a carboxylic acid in the dicyanobenzene-absorbed liquid to a neutralization reaction so as to form an aqueous phase that contains a water-soluble salt, and then subjecting an organic phase and the aqueous phase to liquid-liquid separation so as to remove the aqueous phase, it is possible to remove the carboxylic acid contained in the dicyanobenzene-absorbed liquid with high selectivity while inhibiting loss of the dicyanobenzene.
    Type: Application
    Filed: January 30, 2012
    Publication date: November 7, 2013
    Applicant: Mitsubishi Gas Chemical Company, INC.
    Inventors: Tatsuyuki Kumano, Yukiya Ibi, Kuniaki Arasuna, Shinichi Nagao