Patents by Inventor Girendra Narain Kulsrestha

Girendra Narain Kulsrestha 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 preparation of benzene dicarboxylic acids
    Patent number: 6355835
    Abstract: The present invention relates to a process for the preparation of benzene dicarboxylic acids by liquid phase oxidation of Xylene isomers using oxygen or air by oxidising in the presence of acetic acid as solvent, cobalt salt as catalyst and an initiator. The oxidation step is followed by flashing the said reaction mixture to remove volatile substances and cooling and filtering to get crude benzene di-carboxylic acid as a solid product and filtrate. The dicarboxylic acid solid product is recrystallised to get at least 99% pure benzene. The filtrate may be recycled.
    Type: Grant
    Filed: December 8, 1999
    Date of Patent: March 12, 2002
    Assignee: Chemintel (India) Private Limited
    Inventors: Girendra Narain Kulsrestha, Mahendra Pratap Saxena, Ashok Kumar Gupta, Satish Kumar Sharma, Dinesh Prasad Bangwal, Hari Bhagwan Goyal, Rameshwar Prasad, Sanjib Mall, Prakash D. Patel