Instruction:
Dr. Naum Naveh

This project concerns the recycling of multi-layered sheets composed of three different layers: polyethylene, EVOH, and polyamide. The sheets are manufactured by Plastopil Ltd.

The project’s aim is to recycle the multi-layered sheet by separating the layers to obtain each material separately. The separation is performed by selectively dissolving the middle layer (EVOH) under the influence of ultrasonic waves, to achieve maximum penetrative effect of the solvent and thus recycle the mass-produced multi-layered sheet. The remaining components (polyethylene and polyamide) can then be separated by gravity separation, due to the difference in their specific weights.

The central challenges addressed in the project stem from the “chemical resemblance” between EVOH and polyamide – both polar polymers, which limits the choice of solvents and the method of inserting the solvent into the middle layer of the sheet. HSP (Hansen Solubility Parameters) software was used to choose the solvents.