US 12,187,858 B2
Method for recovering raw materials from polyurethane products
Friedhelm Steffens, Leverkusen (DE); Sebastian Pohl, Langenfeld (DE); Shabnam Majidi Salehi, Cologne (DE); and Jonas Krause, Langenfeld (DE)
Assigned to Covestro Deutschland AG, Leverkusen (DE)
Appl. No. 17/617,430
Filed by Covestro Deutschland AG, Leverkusen (DE); and Covestro Intellectual Property GmbH & Co. KG, Leverkusen (DE)
PCT Filed Jun. 24, 2020, PCT No. PCT/EP2020/067694
§ 371(c)(1), (2) Date Dec. 8, 2021,
PCT Pub. No. WO2020/260387, PCT Pub. Date Dec. 30, 2020.
Claims priority of application No. 19182910 (EP), filed on Jun. 27, 2019; application No. 20176091 (EP), filed on May 22, 2020; and application No. 20181175 (EP), filed on Jun. 19, 2020.
Prior Publication US 2022/0251328 A1, Aug. 11, 2022
Int. Cl. C08J 11/24 (2006.01)
CPC C08J 11/24 (2013.01) [C08J 2375/04 (2013.01)] 15 Claims
OG exemplary drawing
 
1. A method for recovering raw materials from polyurethane products, comprising:
(A) providing a polyurethane product based on an isocyanate component and a polyol component;
(B) reacting the polyurethane product with an alcohol in the presence of a catalyst, to give a first product mixture containing unreacted alcohol, polyols and carbamates and optionally water;
(C) working up the first product mixture, the working up of the first product mixture comprising:
(C.I) combining the first product mixture, obtained in step (B), and without prior removal of any water present in the first product mixture, with an organic solvent which is not fully miscible with the alcohol used in step (B), and performing phase separation into a first alcohol phase and a first solvent phase; and
(C.II) working up the first solvent phase to recover the polyols;
and optionally
(D) working up the first alcohol phase, the working up of the first alcohol phase comprising a step of hydrolyzing the carbamates.