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.:

US 11021839 B1

PDF
Full Text
Expired
Date of Patent:
Jun. 01, 2021

Filed:

Jul. 26, 2018
Applicant:

Unicharm Corporation, Ehime, JP;

Inventors:

Takayoshi Konishi, Kanonji, JP;

Toshio Hiraoka, Kanonji, JP;

Takashi Kato, Kanonji, JP;

Yoshihide Ishikawa, Kanonji, JP;

Noritomo Kurita, Kanonji, JP;

Assignee:
Attorney:
Primary Examiner:
Int. Cl.
CPC ...
D21C 5/02 (2006.01); D21C 9/00 (2006.01); D21C 11/00 (2006.01);
U.S. Cl.
CPC ...
D21C 5/022 (2013.01); D21C 5/02 (2013.01); D21C 9/005 (2013.01); D21C 11/0007 (2013.01);
Abstract

The purpose of the present disclosure is to provide a recovery method for an organic acid. The recovery method makes it possible to efficiently recover an organic acid that is included in a deactivating aqueous solution that includes excrement. This recovery method has the following features. A method for recovering an organic acid that deactivates a highly water-absorbent polymer that is included in used absorbent articles, the method being characterized by including: a deactivation step (S) in which the highly water-absorbent polymer is immersed in a deactivating aqueous solution that includes an organic acid and has a prescribed pH and the highly water-absorbent polymer is deactivated; a highly water-absorbent polymer removal step (S) in which the deactivated highly water-absorbent polymer is removed from the deactivating aqueous solution; a pH adjustment step (S) in which the deactivating aqueous solution is adjusted to a prescribed pH; a concentration step (S) in which the deactivation step (S), the highly water-absorbent polymer removal step (S), and the pH adjustment step (S) are repeated using deactivating aqueous solution that has gone through the pH adjustment step (S) and the organic acid in the deactivating aqueous solution is concentrated; and an organic acid recovery step (S) in which the organic acid is recovered from the deactivating aqueous solution.


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