Monash University engineers have unveiled a new filtering material that could significantly improve the efficiency and sustainability of plastic recycling.
Developed in collaboration with CSIRO and the University of Texas at Austin, the breakthrough centres on a nanocomposite membrane designed to enhance glycolysis, a chemical recycling process used to break down polyethylene terephthalate (PET) plastics.
PET plastics are widely used in everyday products such as drink bottles, food packaging and synthetic textiles. While glycolysis can break these materials down into reusable chemical building blocks, the process has traditionally been hindered by the difficulty and cost of recovering ethylene glycol, a key solvent used in the reaction.
To address this challenge, the research team engineered highly selective nanocomposite membranes capable of separating water from ethylene glycol without relying on energy-intensive methods.
Acting as advanced molecular filters, these membranes enable ethylene glycol to be recovered at high purity and reused in the recycling process.
This innovation has the potential to reduce both chemical consumption and operational costs, making chemical recycling more economically viable and environmentally friendly.
Lead author Dr Hamidreza Mahdavi, a Research Fellow at the Monash Department of Materials Science and Engineering, said the development targets a critical limitation in current recycling systems.
“Instead of only recovering energy from end-of-life plastics, we are trying to recover the building blocks needed to make new materials,” Dr Mahdavi said.
“This is an important step toward a more circular approach to plastic recycling.”
The study demonstrated that the membrane-based separation process can operate under conditions relevant to real-world recycling environments, suggesting strong potential for industrial-scale adoption.
The technology could be applied across a broad range of PET waste streams, including bottles, packaging materials, trays and textiles.
Researchers say the long-term implications are significant.
By improving the recovery and reuse of key chemicals, the innovation could help reduce plastic waste, lower greenhouse gas emissions and strengthen the economic case for advanced recycling technologies.
The findings were published in the Chemical Engineering Journal.
