Patents by Inventor Andre Perrin

Andre Perrin 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 purification of para-nitrophenol
    Patent number: 3954892
    Abstract: In the nitration of phenol with nitric acid, decantation of the residual acid, and steam distillation of ortho-nitrophenol to leave an aqueous distillation residue of para-nitrophenol, a cleaner purer crystalline para-nitrophenol product is obtained by cooling the hot distillation residue when it contains at least 0.5% of sodium bisulphite and is at pH 5.4 to 6.4.
    Type: Grant
    Filed: March 13, 1973
    Date of Patent: May 4, 1976
    Assignee: Rhone-Poulenc, S.A.
    Inventor: Andre Perrin