The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Nov. 19, 2002
Filed:
Oct. 31, 2000
Applicant:
Inventor:
Jean-Pierre Schirmann, Paris, FR;
Assignee:
Atofina, , FR;
Attorney:
Primary Examiner:
Assistant Examiner:
Int. Cl.
CPC ...
C01B 2/116 ;
U.S. Cl.
CPC ...
C01B 2/116 ;
Abstract
A method for preparing hydrazine hydrate comprising: (a) reacting ammonia, hydrogen peroxide and methyl ethyl ketone in a working solution to form an azine; (b) separating the working solution from a mixture comprising the azine, methyl ethyl ketone oxime and optionally the methyl ethyl ketone which had not reacted; (c) recycling the working solution to step (a) after an optional treatment; (d) hydrolyzing the azine to obtain hydrazine hydrate and regenerating the methyl ethyl ketone; (e) recycling to step (a) the methyl ethyl ketone. In step (d) the methyl ethyl ketone oxime is purged.