Multilayer plastic materials present a major challenge at the end of their life cycle because it is very difficult to separate and process their components. This leads to lower recycling efficiency and increases the amount of waste ending up in landfills or incinerators. 

The RECIPLUS project approached this problem using physicochemical delamination, which combines mechanical separation techniques and enzymatic recycling. These approaches have enabled the efficient and sustainable recycling of multilayer waste, so that it can be reintroduced into the value chain or used to produce new recycled plastic products.

To separate and purify the various components of the multilayer structure, they used chemical solvents under supercritical fluid pressure and temperature conditions. This reduced the processing time and solvent usage. The result is a smaller environmental impact and purer separated components.

The project also optimized existing separation technologies with a view to increasing efficiency based on the material mix obtained after delamination. This included various methods such as near-infrared separation, air-flow density separation and triboelectric separation.

Once the different components of the multilayer material (PE, PET and aluminum) have been separated, they can be reintroduced into the value chain, for instance as recycled film or in the production of plastic items. For instance, researchers took recycled polyethylene, applied a further process to modify its properties, and manufactured plant pots as an example of circular economy in the plastics sector.

This project involved AIMPLAS, the Plastics Technology Centre, ACTECO, a company specialising in comprehensive waste management, recovery and valorization, and CEBIMAT LAB, a spin-off from the Jaume I University dedicated to studying material biodegradation.

The work was carried out as part of the RECIPLUS research project, funded by the Valencian Institute for Competitiveness and Innovation (IVACE+i) using ERDF funds.