Detoxification and recycling of contaminated plastic waste streams with hydrothermal liquefaction (HTL)/solvolysis

The present initiative aims at providing a material recycling solution that allows the integration of complex contaminated plastic waste streams in a circular flow of non-toxic plastics. Current handling of such waste is based on incineration and landfill, which is not a sustainable solution.

In a future circular economy, chemical recycling can enable detoxification of complex waste streams to remove persistent and unwanted contaminants in our environment and at the same time provide a stream of recycled polymers and chemicals.In this project we focus on a recycling methodology based on solvolysis in subcritical water, which allows to remove both halogen and metal contaminants by a separation of halogens (bromine and chlorine) and metals from the formed oil product as ions to the water phase.However, the combination with plastic waste streams and fate of additives in chemical recycling have been less investigated.

Our aim is therefore to raise this question in a cross disciplinary team from circular economy, toxic contaminants and chemical recycling.

With this research project we want to investigate how solvolysis (also known as hydrothermal liquefaction, HTL) can be used to recycle the most problematic plastic waste and at the same time break down the dangerous additives (Figure 1).