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:
Jul. 07, 1981
Filed:
Nov. 19, 1979
Applicant:
Inventors:
Assignee:
Kawasaki Kasei Chemicals Ltd., Tokyo, JP;
Primary Examiner:
Int. Cl.
CPC ...
B01D / ;
U.S. Cl.
CPC ...
55 85 ; 260707 ; 260D / ; 562408 ; 562485 ;
Abstract
A scale deposition from an aqueous slurry of naphthoquinone and phthalic acid can be prevented by adding fine crystals of phthalic acid to the aqueous slurry of naphthoquinone and phthalic acid collected, which slurry is obtained by contacting a gas resulting from a catalytic gas phase oxidation of naphthalene with water or a mother liquor recycled. The fine crystals of phthalic acid have diameters of less than 100.mu., preferably 10 to 40.mu., and can be in an aqueous slurry of phthalic acid pulverized by a pulverizer.