Applications are invited for a fully-funded PhD position working with Prof. Stephen Connon based in the School of Chemistry, Trinity College Dublin on an exciting project to develop new catalytic methodologies for the catalysis of plastic recycling. Poly(ethylene terephthalate) (or PET) is an oil-derived very common polyester thermoplastic with a global synthesis rate of >800 kg per second and a landfill half life estimated at >2500 years. The production of these and other plastics and their accumulation in the natural world impacts human health considerably at every life stage and is contributing to the current climatological and environmental emergency. Most plastic recycling is mechanical in nature and leads to recycling plastic of inferior quality, downcycling and eventual landfill. Chemical recycling (i.e. breaking down the plastic to monomers which can be purified and re-synthesised into pristine plastic is an emerging, far more sustainable and circular technology - however it relies on efficient catalysis that can be sustainably used at scale.
We have recently shown that it is possible to design catalysts for the recycling of PET and other plastics which are unprecedentedly active and sustainable. This is important, as in the future chemical recycling (which currently represents only 0.1% of total plastic production) will need to be carried out on enormous scales, all around the globe. We wish to design catalysts for the depolymerisation of PET and similar materials which operate via novel mechanisms and which themselves are eminently sustainable. Our group is passionate about this - we believe the future of recycling will be powered by catalysts which are both highly efficient and highly sustainable. As an example, to chemically recycle 10% of the amount of PET produced in 2023 with a catalyst active at 0.5 wgt% levels (pretty active), 12.5 million kg of catalyst would be required globally. This project involves using mechanistic understanding to design, synthesise and evaluate the performance of the next generation of PET recycling catalysts with sustainability of the catalyst itself as a core-design feature. This is an exciting goal: we must not only face the chemical challenge presented by trying to catalyse the organic reaction itself, we must also achieve this using systems that can be generated and used economically at scale by others, with minimal environmental impact. We also plan to design catalysts for efficient upcycling of PET (i.e. turning water bottle waste into higher value products). The successful student will also collaborate with groups in the polymer synthesis and computational chemistry fields.
The successful candidate will have, or be about to obtain, a degree (2.1 or higher) in chemistry (or related discipline) interested in organic synthesis and catalysis. Would also suit a person enthusiastic about utilising their organic chemistry skills to help alleviate environmental problems.
Competitive stipend available, EU-status fees only
Recent relevant references
‘Upcycle to recycle: triglyceride-derived magnesium soaps as stable, sustainable and efficient catalysts for poly(ethylene terephthalate) glycolysis', L. Pedrini, A. Jain, L. Kenny, D. T. Mannion, K. N. Kilcawley and S J. Connon*, RSC Sustainability, 2026, 4, 770.
‘Rapid catalytic recycling of poly(ethylene terephthalate): minimal hydroxide, minimal biomass-derived recyclable cosolvent', A. Jain, E. Killian and S. J. Connon*, ChemSusChem. 2025, 18, e202501392.
‘Catalytic alkaline hydrolysis of PET and BPA-PC waste in minutes at atmospheric pressure without microwaves or organic solvents ', A. Jain and S. J. Connon*, Green Chem. 2025, 27, 4986.
‘Neutral hydrolysis of poly(ethylene terephthalate) catalysed by highly active terephthalate-based ionic liquids at low loadings', I. L. Martin, L. B. Anderson, D. A. McAdams, C. Molloy, P. W. Dunne and S. J. Connon*, Chem. Commun. 2025, 61, 2750.
‘Ionic liquid catalysts for poly(ethylene terephthalate) glycolysis: use of structure activity relationships to combine activity with biodegradability', L. Pedrini, C. Zapelli and S. J. Connon*, ACS Sustainable Chem. Eng. 2025, 13, 1424 .
‘Effect of phase transfer catalyst structure on the alkaline hydrolysis of poly(ethylene terephthalate)', L. B. Anderson, C. Molloy, L. Pedrini, I. L. Martin and S. J. Connon*, Green Chem. 2024, 26, 11125.
'Cholinium-based ionic liquid catalysts for polyethylene terephthalate glycolysis: understanding the role of solvent and a reappraisal of the cation contribution', D. Bura, L. Pedrini, C. Trujillo* and S. J. Connon*, RSC Sustainability, 2023, 1, 2197.