JPWO2020260387A5

JPWO2020260387A5 -

Info

Publication number: JPWO2020260387A5
Application number: JP2021577182A
Authority: JP
Publication date: 2023-07-03

Claims

(A) preparing a polyurethane product made from an isocyanate component and a polyol component;
(B) reacting the polyurethane product with an alcohol in the presence of a catalyst to obtain a first product mixture containing unreacted alcohol, polyol and carbamate, and optionally water;
(C)
(C.I) the first product mixture obtained in step (B), without prior removal of the water present in the first product mixture, combining with an organic solvent that is not completely miscible with the alcohol and causing phase separation into a first alcoholic phase and a first solvent phase;
(C.II) post-treating the first solvent phase to recover the polyol;
post-treating the first product mixture comprising
optionally,
(D) post-treating the first alcoholic phase comprising hydrolyzing the carbamate;
A method of recovering raw materials from polyurethane products, comprising:

Step (C.II) is
(C.II.1) scrubbing the first solvent phase with an aqueous scrubbing solution and phase separation into a second solvent phase, an emulsion phase and optionally a first aqueous phase;
(C.II.2) post-treating the second solvent phase to recover the polyol;
2. The method of claim 1, comprising:

Step (C.II) is
(C.II.3) the emulsion phase,
(C.II.3.a) combined with an organic solvent and undergoing phase separation into a third solvent phase and a second aqueous phase, or
(C.II.3.b) combining with said first alcoholic phase and an organic solvent and undergoing phase separation into a third solvent phase and a second alcoholic phase;
(C.II.4) returning said third solvent phase to step (C.I) or step (C.II.1);
3. The method of claim 2, further comprising:

step (C.II.3.a);
(D.I.a) evaporating the alcohol fraction from said first alcohol phase leaving a carbamate phase;
(D.II.a) hydrolyzing the carbamate phase with an aqueous phase to obtain an amine phase, (D.III) recovering the amine corresponding to the isocyanate of the isocyanate component from the amine phase,
4. The method of claim 3, comprising step (D) comprising:

step (C.II.3.b);
(D.I.b) hydrolyzing said second alcoholic phase with an aqueous phase to obtain an amine-water-alcohol mixture;
(D.II.b) evaporating water from said amine-water-alcohol mixture to obtain an amine-alcohol mixture and then evaporating the alcohol fraction from said amine-alcohol mixture leaving an amine phase;
(D.III) recovering the amine corresponding to the isocyanate of the isocyanate component from the amine phase;
4. The method of claim 3, comprising step (D) comprising:

(E) providing a crude product fraction of an amine that is the same amine as that recovered in step (D.III), wherein said crude product fraction comprises, in addition to said amine, less than said amine; a process that contains organic impurities that boil at a higher boiling point,
further comprising
Step (D.III) is
(D.III.1) mixing said amine phase with said crude product fraction and post-treating the resulting mixture to remove amines contained in said crude product fraction from amines recovered from said amine phase; to obtain with
6. A method according to claim 4 or 5 , comprising

Said crude product fraction is removed from the bottom fraction of the distillation in order to purify the amine contained in said crude product fraction and is boiled at a higher boiling point than said amine in step (D.III.1) a solid residue containing organic impurities is additionally obtained,
or
Said crude product fraction is removed from the crude product of a process for producing the amine contained in said crude product fraction, and in addition to organic impurities boiling at a higher boiling point than said amine, and water, which is fed to distillation to remove the water, including the amine, organic impurities boiling more readily than the amine, and organic impurities boiling at a higher boiling point than the amine. 7. Process according to claim 6 , wherein a bottoms fraction is obtained, as well as an overhead fraction comprising removed water.

The step (E) is
(E.I) catalytically hydrogenating a nitro compound corresponding to an amine present in said crude product fraction to, in addition to said amine, organic impurities boiling at a higher boiling point than said amine; obtaining a crude product containing readily boiling organic impurities and water;
(E.II) removing water from said crude product to obtain a water depleted process product;
(E.II) distilling the water depleted process product to contain a distillate fraction of the amine present in the crude product fraction and organic impurities boiling at a higher boiling point than the amine; obtaining a bottoms fraction;
8. The method of claim 7 , comprising:

In step (C.I),
said organic solvent is selected from the group consisting of aliphatic hydrocarbons, alicyclic hydrocarbons, aromatic hydrocarbons, and mixtures of two or more of said organic solvents;
said alcohol consists of methanol, ethanol, ethylene glycol, diethylene glycol, propylene glycol, dipropylene glycol, methyl glycol, triethylene glycol, glycerol, 2-methyl-1,3-propanediol, and mixtures of two or more of said alcohols; A method according to any one of claims 1 to 8 , selected from the group.

Water in step (B), if present, has a mass fraction of water of 0% to 5.0% based on the total mass of polyurethane product, catalyst, alcohol and water present in step (B) and no additional water is added during the reaction of the polyurethane product with the alcohol in the presence of the catalyst. .