Polyurethane foam degradation combining ozonization and mealworm biodegradation and its exploitation

Area of Science:

• Environmental Science
• Biotechnology
• Materials Science

Background:

• Polyurethane foam (PU foam) is a persistent environmental pollutant.
• Biodegradation offers a sustainable solution for PU foam waste management.
• Tenebrio molitor (mealworms) have shown potential in degrading various waste materials.

Purpose of the Study:

• To investigate the biodegradation of PU foam using Tenebrio molitor (mealworms) with prior ozonization.
• To assess the impact of different ozone oxidation levels on PU foam degradation by mealworms.
• To evaluate the potential of mealworm byproducts for circular economy applications.

Main Methods:

• PU foam was treated with varying degrees of ozone oxidation (0%, 25%, 50%).
• Tenebrio molitor mealworms were fed the treated PU foam, and their consumption, survival, and growth were monitored.
• Fourier transform infrared (FTIR) spectroscopy and differential scanning calorimetry (DSC) analyzed structural changes.
• Gut microbiota composition was analyzed to understand degradation mechanisms.

Main Results:

• Mealworm consumption rates were highest for non-oxidized PU foam and decreased with increased oxidation.
• Mealworm survival rates were comparable across all PU foam diets and a control bran diet.
• FTIR and DSC indicated minor structural alterations in the PU foam.
• Gut microbiota analysis revealed diet-specific microbial communities, with Klebsiella prevalent in PU foam diets.

Conclusions:

• Ozone pre-treatment influences PU foam palatability and degradation by mealworms.
• Tenebrio molitor can degrade PU foam, with potential for resource recovery (frass, chitin).
• This approach supports the development of a circular bio-economy by valorizing PU foam waste.