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.

Date of Patent:
Nov. 04, 1980

Filed:

Jun. 05, 1978
Applicant:
Inventor:

Alfred Schmidt, Vienna, AT;

Assignee:
Attorney:
Primary Examiner:
Int. Cl.
CPC ...
C07C / ;
U.S. Cl.
CPC ...
564 73 ; 208 25 ;
Abstract

Disclosed is a process and apparatus for purifying and regenerating urea solutions which have been contaminated with biuret and triuret and the like during the use of the urea solutions such as in dewaxing processes. The contaminated urea solution is first contacted with ammonia in gaseous or liquid form and about one to ten percent of the ammonia is absorbed into the contaminated solution. The contaminated solution and absorbed ammonia are reacted in a reactor with heating for a period of time sufficient to complete the reaction of biuret and triuret to produce urea. The purified product solution may then be returned for further use in dewaxing processes. Excess ammonia and CO.sub.2 formed during the reaction process by the decomposition of urea may optionally be separated from the purified solution and from each other with the separated excess ammonia being returned to the absorber for reuse.


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