Granted Patent B2

US 12,503,566 · App. 18/857,370 · Granted Dec 23, 2025

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

Assignee: Revalyu Resources GmbH

C08J11/24C08J2367/02

Abstract

Claims (30)

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. pre-coating a filtering means with the first particulated material;

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

wherein

the first particulated material has a median pore diameter in the range of 10 mm to 20 mm,

the first particulated material is diatomaceous earth, and

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,

with the intrinsic viscosity, the wt-% of the first intermediate product in the form of oligomers, and the median pore diameter of the first particulated material 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 first particulated material has a pore diameter distribution with at least one mode in the range of 8 000 nm to 20 000 nm, with the mode determined according to the method described herein.

5 . The method according to claim 1 , wherein the first particulated material has a pore diameter distribution with at least two modes in the range of 8 000 nm and 20 000 nm, and wherein

a. at least one mode is in the range of 8 000 nm to 15 000 nm;

b. at least one mode is in the range of >15 000 nm to 20 000 nm;

with the at least one mode determined according to the method described herein.

6 . The method according to claim 1 , wherein the first particulated material has a pore diameter distribution with at least one first mode in the range of 9 000 nm to 15 000 nm, and at least one further mode in the range of >15 000 nm to 20 000 nm, wherein a ratio of the first mode to the further mode is in the range of 0.30 to 1.00, with the modes determined according to the method described herein.

7 . The method according to claim 1 , wherein the first particulated material has at least one or all of the following properties:

a. a cumulative pore volume in the range of 0.6 cm 3 /g to 1.9 cm 3 /g for pores with a diameter in the range of 9000 nm and 20 000 nm;

b. a cumulative pore volume in the range of 0.5 cm 3 /g to 1.4 cm 3 /g for pores with a diameter in the range of 10 000 nm and 15 000 nm;

c. a cumulative pore volume in the range of 0.10 cm 3 /g to 0.80 cm 3 /g for pores with a diameter in the range of >15 000 nm to 20 000 nm;

with the cumulative pore volume determined according to the method described herein.

Assignments (1)

Priority Claims (1)

Continuity (1)

References Cited (161)