Granted Patent B2

US 12,595,352 · App. 18/857,362 · Granted Apr 7, 2026

Inventors: Suresh L. Makhija (Mumbai, IN); Dhanvant Yeola (Nashik, IN); Christian Neumann (Hanau, DE)

Assignee: Revalyu Resources GmbH

C08J11/24C08J2367/02

Abstract

Claims (20)

1 . A method for producing a first intermediate product, comprising the steps of

a. providing a feedstock that comprises a first polyester;

b. contacting the first polyester with a further organic compound in a volume section V 3 , to obtain a further initial mixture;

c. reducing a weight average molar mass of the first polyester in the volume section V 3 , to obtain a first intermediate mixture, wherein the first intermediate mixture comprises

i. a first intermediate product that has an intrinsic viscosity in the range of 0.010 dL/g to 0.120 dL/g,

ii. the further organic compound;

d. adding first particulated material to the first intermediate mixture in a volume section V 4 ;

e. transporting the first intermediate mixture to a filtering means;

f. at least partially removing at least one impurity from the first intermediate mixture using the filtering means;

wherein

a temperature of the first intermediate mixture in the volume section V 4 is in the range of 170° C. to 220° C., and wherein at least 40 wt-% of the first intermediate product is in the form of oligomers that have in the range of 2 to 35 repeating units, and wherein the first particulated material is diatomaceous earth,

with the intrinsic viscosity, the wt-% of the first intermediate product in the form of oligomers, and the temperature in the volume section V 4 determined according to the methods described herein.

2 . The method according to claim 1 , wherein the first polyester is selected from the group consisting of a polyethylene terephthalate, a polybutylene terephthalate, a polylactide, a polytrimethylene terephthalate, a polyethylene naphthalate, a polycarbonate, a polyester carbonate, a polyarylate, a polyester resin, and a combination of two or more thereof.

3 . The method according to claim 1 , wherein the further organic compound has at least one or all of the following properties:

a. comprises at least two hydroxyl groups;

b. a molar mass of at least 60 g/mol;

c. a boiling point of at least 192° C.

4 . The method according to claim 1 , wherein the temperature of the further initial mixture in the volume section V 3 is in the range of 180° C. to 220° C., with the temperature determined according to the method described herein.

5 . The method according to claim 1 , wherein the first intermediate mixture comprises at least 70 wt-% of the first intermediate product, with the wt-% determined according to the method described herein.

6 . The method according to claim 1 , wherein the method further comprises the step of at least partially removing at least one impurity from the first intermediate mixture.

Assignments (1)

Priority Claims (1)

Continuity (1)

References Cited (161)