Plastics are predominantly well suited for thermal recovery, however, only their calorific value is used for power and heat generation. The carbon bound in the polymer is lost as CO2 and contributes to global warming – not a sustainable end-of-life concept.
Most polymers are thermoplastic and can therefore easily be brought into a new shape and function by re-melting. However, this so-called mechanical recycling has some disadvantages, as only clean and pure polymers can be used. Polymers with added colourants and other additives as well as a constant decreasing quality due to environmental influence, mechanical stress and contamination inevitably leads to “downcycling”. Recyclates obtained by conventional mechanical recycling do not yet always fulfil the high requirements for food packaging regarding purity and mechanical properties of the materials.
In contrast to thermal recovery or mechanical recycling of plastic waste, chemical recycling aims for real closing of the loop.