Polyethylene terephthalate (PET) is one of the most widely utilized polymers nowadays in an
extensive range of products and packaging system, and accounts for 12% of the world’s total
solid waste. Effective and efficient chemical recycling technologies are emerging as high
potential sustainable routes with considerable benefits over conventional recycling methods for
the achievement of circular economies for PET postconsumer plastic waste. Herein, a single step
hydrolytic depolymerization and product purification of colored postconsumer PET, was carried
out under conventional heating demonstrating excellent efficiencies. Optimized hydrolysis-purification
conditions were determined using Box Behnken Design (BBD) to attain maximum weight loss of
PET and percentage yield of terephthalic acid (TPA) monomer while achieving high acid value
and transparency of TPA as its purity indicators. Within 30-40 minutes, the proposed hydrolytic
depolymerization-purification technology was able to facilitate ≈96% conversion of PET to TPA
monomer with improved acid value and color properties.
Furthermore, taking into consideration the industrial scale depolymerization of PET with factors
like plant installation and maintenance costs, skilled labor requirements and safety, the single
step depolymerization-purification route demonstrated by the proposed technique can present an
attractive economic and environmentally sustainable approach for postconsumer PET and other
polyesters recycling and circularity.