As a modern processing technique, 3D printing has revolutionized catalyst fabrication by enabling complex geometries like triply periodic minimal surface structures, which enhance surface area, mass transfer, and mechanical stability, improving overall catalysts efficiency. Metal-based catalysts, such as zinc, manganese, and titanium, have proven effective in the chemical recycling of polyethylene terephthalate (PET). However, concerns regarding toxicity and environmental impact highlight the need for less toxic alternatives. Sustainable catalysts such as sodium carbonate have been investigated for PET glycolysis, providing an environmentally friendly approach.
This study investigates the degradation of PET using sodium carbonate powder as a sustainable catalyst, with the long-term goal of developing a printable formulation for 3D-printed catalytic structures. While previous work has demonstrated the successful integration of titanium oxide into SLA resins and nickel nitrate into PLA filaments for FDM, sodium carbonate has not yet been incorporated into a printable matrix. Current efforts focus on assessing the catalytic efficiency of sodium carbonate in powder form during PET glycolysis and understanding its potential for future resin integration.
Three types of PET waste were analyzed using differential scanning calorimetry (DSC) and thermogravimetric analysis (TGA) to assess their thermal behavior and degradation potential. The glycolysis product, bis(2-hydroxyethyl) terephthalate (BHET), was confirmed through Fourier transform infrared spectroscopy (FTIR), DSC, and both proton and carbon nuclear magnetic resonance (¹H and ¹³C NMR). These results support the use of sodium carbonate as an effective catalyst in PET glycolysis and provide a basis for future integration into eco-friendly, 3D-printed catalytic systems.