Produção de Poliéster PET via Policondensação

Das garrafas de bebidas às fibras têxteis

Petrochemical & Refining Global Industrial Scale $55 billion

Visão geral

Polyethylene terephthalate (PET) is produced by polycondensation of ethylene glycol with terephthalic acid (PTA). PET is the world's most recycled plastic, used for beverage bottles, food packaging, and polyester textile fibers. The two-stage process involves esterification followed by melt polycondensation under vacuum. Global PET production exceeds 90 million tons annually, with approximately 70% used for fibers and 30% for packaging.

Processo químico

Purified terephthalic acid (PTA) is esterified with ethylene glycol (EG) at 240-260 degrees C to form bis(2-hydroxyethyl) terephthalate (BHET). The BHET undergoes melt polycondensation at 270-290 degrees C under high vacuum (<1 mbar) using antimony trioxide catalyst, removing ethylene glycol to build molecular weight. Solid-state polymerization (SSP) further increases IV for bottle-grade resin.

nHOOC-C₆H₄-COOH + nHOCH₂CH₂OH →[Sb₂O₃, 280 degrees C, vacuum] −(OC-C₆H₄-CO-OCH₂CH₂O)ₙ− + (2n-1)H₂O

Matérias-primas

  • Purified terephthalic acid (PTA, C₈H₆O₄) — Oxidation of p-xylene (Diacid monomer)
  • Ethylene glycol (C₂H₆O₂) — Hydration of ethylene oxide (Diol monomer)
  • Antimony trioxide (Sb₂O₃) — Mining and smelting (Polycondensation catalyst)

Produtos finais

  • PET resin (chips/pellets) — Bottles, packaging, polyester fibers (IV 0.60-0.84 dL/g depending on grade)
<path stroke-linecap="round" stroke-linejoin="round" d="M12 9v3.75m-9.303 3.376c-.866 1.5.217 3.374 1.948 3.374h14.71c1.73 0 2.813-1.874 1.948-3.374L13.949 3.378c-.866-1.5-3.032-1.5-3.898 0L2.697 16.126zM12 15.75h.007v.008H12v-.008z" />

Environmental Impact

PET is the most recycled plastic with established mechanical and chemical recycling infrastructure. However, production from fossil feedstocks contributes to CO₂ emissions. Antimony catalyst traces in PET have raised health concerns. Microfiber shedding from polyester textiles is a growing environmental issue.

Considerações de segurança

Inovações recentes

Bio-based PET using plant-derived ethylene glycol and furandicarboxylic acid (PEF) as a drop-in replacement is in commercial development.
Enzymatic depolymerization by PETase enzymes enables closed-loop chemical recycling under mild conditions.

Escala de produção

90000000

toneladas/ano

$55 billion

valor de mercado

Mais em Petrochemical & Refining

Craqueamento a Vapor para Produção de Etileno

Global Industrial Scale

Destilação Fracionada do Petróleo Bruto

Global Industrial Scale

Polimerização do Polietileno

Global Industrial Scale

Produção de Óxido de Etileno via Oxidação Catalítica com Prata

Global Industrial Scale

Produção de Polipropileno via Catálise Ziegler-Natta

Global Industrial Scale

Reforma Catalítica para Gasolina de Alto Octano

Global Industrial Scale

Síntese de Fischer-Tropsch para Combustíveis Sintéticos

Commercial Production

Frequently Asked Questions

What industry uses Produção de Poliéster PET via Policondensação?
Produção de Poliéster PET via Policondensação is used in the petrochemical & refining sector at global industrial scale scale.
What process is involved in Produção de Poliéster PET via Policondensação?
Purified terephthalic acid (PTA) is esterified with ethylene glycol (EG) at 240-260 degrees C to form bis(2-hydroxyethyl) terephthalate (BHET). The BHET undergoes melt polycondensation at 270-290 degrees C under high vacuum (<1 mbar) using antimony trioxide catalyst, removing ethylene glycol to buil
What is the economic significance of Produção de Poliéster PET via Policondensação?
Produção de Poliéster PET via Policondensação has a market value of $55 billion and annual production of 90,000,000 tons.
What is the environmental impact of Produção de Poliéster PET via Policondensação?
PET is the most recycled plastic with established mechanical and chemical recycling infrastructure. However, production from fossil feedstocks contributes to CO₂ emissions. Antimony catalyst traces in PET have raised health concerns. Microfiber shedding from polyester textiles is a growing environme
What raw materials are used in Produção de Poliéster PET via Policondensação?
The main raw materials include: Purified terephthalic acid (PTA, C₈H₆O₄), Ethylene glycol (C₂H₆O₂), Antimony trioxide (Sb₂O₃).