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(12) PATENT APPLICATION PUBLICATION
(19) INDIA (21) APPLICATION No:
1685/MAS/1998A
(22) Date of filing of Application:29/07/1998 (43) Publication Date: 09/06/2006
(54) Title of the invention:
A PROCESS FOR THE PREPARATION
OF AN AQUEOUS SOLUTION OF FREE
HYDROXYLAMINE
(51)International classification: C01B 21/14
(31) Priority Document No.19733681.7
(32) Priority Date:04/08/1997
(33) Name of priority country: GERMANY
(87) WIPO No.: PCT/EP98/04850
(61) Patent of addition to
Application No. :
Filed on:
(62) Divisional to
Application No.:
Filed on:
(71) Name of Applicant
BASF AKTIENGESELLSCHAFT
Address of Applicant:
67056 LUDWIGSHAFEN,
GERMANY.
(72) Name of the Inventor(s):
Dr. OTTO WATZENBERGER
SEDANSTR,
PETER MAUER,
Dr. ECKHARD STROFER,
HEINER SCHELLING,
Dr. HANS-MICHAEL SCHNEIDER.
(57) Abstract
An aqueous solution of free hydroxylamine is prepared by treating a hydroxyl ammonium salt with ammonia
by the countercurrent method in a stripping column by a process in which hydroxylamine is liberated and at the same
time the solution obtained is separated by distillation into an aqueous hydroxylamine solution and a salt fraction. The
novel process can be carried out in a simple and I gentle manner and on a large scale. The danger of decomposition is
minimized owing to the low thermal load, the low concentration of hydroxylamine and the short residence time in the
process.
The Patent Office Journal 09/06/2006 10791