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. 26, 1991
Filed:
May. 17, 1989
Applicant:
Inventors:
Yoshiro Ashina, Yokohama, JP;
Takeyuki Fujita, Yokohama, JP;
Kiyonobu Niwa, Yokohama, JP;
Takeshi Inagaki, Yokohama, JP;
Yuko Nikaido, Yokohama, JP;
Assignee:
Nitto Kagaku Kogyo Kabushiki Kaisha, Tokyo, JP;
Attorney:
Primary Examiner:
Assistant Examiner:
Int. Cl.
CPC ...
C07C / ;
U.S. Cl.
CPC ...
564479 ; 564474 ;
Abstract
There is provided a method for maintaining the activity of a zeolite catalyst in the catalytic production of methylamines from methanol and ammonia using a zeolite catalyst as at least one of catalysts applied, which comprises controlling the amount of aldehyde compounds as impurities flowing into a zeolite catalyst layer to about 0.15 g/hr.kg-cat. or lower, as calculated in terms of formaldehyde.