Catalysts and method for producing recycled polyester

Patent metadata

Field	Value
Publication number	US-12577366-B2
Application number	US-201917275856-A
Country	US
Kind code	B2
Filing date	Sep 12, 2019
Priority date	Sep 12, 2018
Publication date	Mar 17, 2026
Grant date	Mar 17, 2026

Abstract

The present invention describes the preparation of heterogeneous catalysts of mixed oxides based upon niobium and mixed oxides of zinc, manganese, nickel, cobalt and/or aluminum, originating from hydrotalcites (HTs) as precursor phase of heterogeneous catalysts, and application thereof in the chemical recycling of poly(ethylene terephthalate) (PET) for the production of metal free bis(hydroxy)ethylene (BHET) monomers and oligomers having a processing performance similar to that of the homogeneous catalysis system.

First claim

The invention claimed is:

1 . A catalyst for the obtainment of recycled polyester, comprising the following general formulas:
(Zn 0.67 Mn 0.33 ) (1-x) Al x (OH) 2 (CO 3 ) x/2 .m H 2 O  (II);
(Ni a Mn b ) (1-x) Al x (OH) 2 (A n− ) x/n .m H 2 O  (IV);
(Zn a Mn b ) (1-x) Al x (OH) 2 (A n− ) x/n .m H 2 O  (V); and
(Co 0.67 Mn 0.33 ) (1-x) Al x (OH) 2 (CO 3 ) x/2 .m H 2 O  (VII),

wherein
0.2 ≤x≤ 0.5,
0.1 ≤a/b≤ 5,
A n− =anion of compensation, which may be carbonate, terephthalate or another anion, and
m= 1−(3/2) x+ 0.125.

2 . The catalyst of claim 1 , the catalyst having the following general formula:
(Co 0.67 Mn 0.33 ) (1-x) Al x (OH) 2 (CO 3 ) x/2 .m H 2 O  (VII),
wherein x=0.20 and m=1−(3/2)x+0.125.

3 . A catalyst for the obtainment of recycled polyester, the catalyst consisting essentially of one of the following general formulas:
(Zn 0.67 Mn 0.33 ) (1-x) Al x (OH) 2 (CO 3 ) x/2 .m H 2 O  (II);
(Ni a Mn b ) (1-x) Al x (OH) 2 (A n− ) x/n .m H 2 O  (IV);
(Zn a Mn b ) (1-x) Al x (OH) 2 (A n− ) x/n .m H 2 O  (V); and
(Co 0.67 Mn 0.33 ) (1-x) Al x (OH) 2 (CO 3 ) x/2 .m H 2 O  (VII),

wherein
0.2 ≤x≤ 0.5,
0.1 ≤a/b≤ 5,
A n− =anion of compensation, which may be carbonate, terephthalate or another anion, and
m= 1−(3/2) x+ 0.125.

Assignees

• Petroleo Brasileiro S A —Petrobras
• Univ Federal Do Rio De Janeiro—Ufrj
• Univ Federal De Pernambuco—Ufpe

Inventors

• De Oliveira Da Silva Wellington
• Hallen Lima Stevie
• Lopes Dias Marcos
• Sirelle Lys
• De Andrade Pacheco Filho Jose Geraldo
• Nascimento De Andrade Jacicleide
• Do Nascimento Júnior Hezrom Saulo
• Bastos Lopes Daniela Emilia
• Cipriano De Arcanjo Ana Paula
• Machado De Castro Aline

Classifications

• B01J35/40

  characterised by dimensions, e.g. grain size (in a colloidal state B01J35/23; crystallite size B01J35/77) · CPC title

• C08J2367/02

  Polyesters derived from dicarboxylic acids and dihydroxy compounds; (C08J2367/06 takes precedence) · CPC title

• C08G63/183

  Terephthalic acids · CPC title

• C07C67/02

  by interreacting ester groups, i.e. transesterification · CPC title

• B01J23/8892

  Manganese · CPC title