Chemical depolymerisation of PET complex waste: hydrolysis vs. glycolysis

  • Alicia Aguado
  • L. Martínez
  • L. Becerra
  • M. Arieta-araunabeña
  • S. Arnaiz
  • A. Asueta
  • I. Robertson


The huge increase in the generation of post-consumer plastic waste has produced a growing interest in eco-efficient strategies and technologies for their appropriate management and recycling. In response to this, PROQUIPOL Project is focused on developing, optimizing and adapting feedstock recycling technologies as an alternative for management for the treatment of complex plastic waste. Among the different plastic wastes studied, PROQUIPOL Project is working on providing a suitable treatment to the highly colored and complex multilayered post-consumer waste fractions of polyethylene terephthalate (PET) by chemical depolymerisation methods. Glycolysis and alkali hydrolysis processes have been studied with the aim of promoting the transformation of PET into the bis(2-hydroxyethyl) terephthalate monomer and terephthalic acid, respectively. In both cases operational conditions such as temperature, reaction time, catalyst to PET rate and solvent to PET rate have been considered to optimize product yield, achieving values near to 90 % and monomer purities over 95 % in both processes. This paper presents results obtained for each treatment as well as a simplified comparison of technical, economic and environmental issues.


Depolymerisation Alkali hydrolysis Glycolysis PET waste 



The authors wish to acknowledge the confidence for and economic support of the Spanish Ministry of Education and Science to this work by financing the PROQUIPOL Project “Reference PID-560620-2009-4” and the supply of actual post-consumer waste samples of PET by ECOEMBES.


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Copyright information

© Springer Japan 2013

Authors and Affiliations

  • Alicia Aguado
    • 1
  • L. Martínez
    • 1
  • L. Becerra
    • 1
  • M. Arieta-araunabeña
    • 2
  • S. Arnaiz
    • 2
  • A. Asueta
    • 2
  • I. Robertson
    • 2
  1. 1.Environmental Division, CARTIF Centro TecnológicoBoecilloSpain
  2. 2.GAIKER Technology CenterZamudioSpain

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