Sustainability within the polyester value chain
type: CreativeWork
description: Polyethylene terephthalate (PET) is used to make textile fibres, bottles and packaging films. The global production in 2013 was 65 Mt, growing at 5-7% per year over the last decade. PET is manufactured by the continuous polymerisation of ethylene glycol and terephthalic acid, both of which are produced from fossil fuels. This Dissertation examines the environmental impact of manufacturing PET using process modelling and life cycle assessment. The work focused on ways of reducing the environmental impact of the polymer manufacture by using biomass instead of conventional fossil fuels, either as a raw material for producing ethylene glycol or terephthalic acid, or as a fuel to supply process heating or electricity. The environmental impacts of producing a PET bottle using ethylene glycol derived from two types of biomass, sugarcane and willow, were investigated and compared with conventional production. For sugarcane, the sugars were fermented to bioethanol, then dehydrated to ethylene. By using sugarcane, it was found that the global warming potential (GWP) and non-renewable resource use could be reduced by 28% and 16% respectively. Ethanol, and hence ethylene, can also be produced from willow, a lignocellulosic biomass, which could also potentially reduce nonrenewable resource use by 16%. However, for sugarcane there was a significant increase in other environmental impacts, e.g. acidification and eutrophication potential; these increases were smaller when using willow. From supply chain analysis, the transport of finished and intermediate products only made a minor contribution to the environmental impacts. The principal raw material for terephthalic acid is p-xylene, conventionally made from naphtha. It is feasible, however, to manufacture p-xylene by the catalytic conversion of sugars extracted from biomass sources. A PET bottle made using p-xylene derived from willow could reduce the GWP and non-renewable energy use by 32% and 2%, respectively, or 87% and 26% us…
abstract: Polyethylene terephthalate (PET) is used to make textile fibres, bottles and packaging films. The global production in 2013 was 65 Mt, growing at 5-7% per year over the last decade. PET is manufactured by the continuous polymerisation of ethylene glycol and terephthalic acid, both of which are produced from fossil fuels. This Dissertation examines the environmental impact of manufacturing PET using process modelling and life cycle assessment. The work focused on ways of reducing the environmental impact of the polymer manufacture by using biomass instead of conventional fossil fuels, either as a raw material for producing ethylene glycol or terephthalic acid, or as a fuel to supply process heating or electricity. The environmental impacts of producing a PET bottle using ethylene glycol derived from two types of biomass, sugarcane and willow, were investigated and compared with conventional production. For sugarcane, the sugars were fermented to bioethanol, then dehydrated to ethylene. By using sugarcane, it was found that the global warming potential (GWP) and non-renewable resource use could be reduced by 28% and 16% respectively. Ethanol, and hence ethylene, can also be produced from willow, a lignocellulosic biomass, which could also potentially reduce nonrenewable resource use by 16%. However, for sugarcane there was a significant increase in other environmental impacts, e.g. acidification and eutrophication potential; these increases were smaller when using willow. From supply chain analysis, the transport of finished and intermediate products only made a minor contribution to the environmental impacts. The principal raw material for terephthalic acid is p-xylene, conventionally made from naphtha. It is feasible, however, to manufacture p-xylene by the catalytic conversion of sugars extracted from biomass sources. A PET bottle made using p-xylene derived from willow could reduce the GWP and non-renewable energy use by 32% and 2%, respectively, or 87% and 26% us…
author: Van Uytvanck, Pieterjan Paul
language: en
license: https://www.repository.cam.ac.uk/bitstreams/4c5a2896-c0b3-4058-a05b-8f3cce83d874/download
license: https://www.rioxx.net/licenses/all-rights-reserved/
license: https://www.repository.cam.ac.uk/bitstreams/85bf926d-f1c1-4d00-ad95-b749e7a38b91/download
date published: 2015-06-30
date modified: 2026-07-22T22:23:57Z
provider: Cambridge University
publisher: Networked Digital Library of Theses and Dissertations
type: WebPage
source organization: University of Cambridge

PropertyValue
property ID: DOI
value: 10.17863/CAM.6929