بازيافت شيميايي پلي اتيلن ترفتالات به ترفتاليك اسيد به وسيله آبكافت با سولفوريك اسيد

Obtaining Terephathalic Acid by Chemical Recycling of Polyethylene Terephthalate via Hydrolysis Using Sulphuric Acid

Polyethylene terephthalate (PET) is one of the most important thermoplastics due to its special properties and applications. Different methods have been developed for recycling PET waste. Hydrolysis is a chemical method for recycling of PET waste. Advantages of this method are: direct conversion to terephthalic acid (TPA) and ethylene glycol (EG) with high purity and low cost. In this research, the depolymerization of PET to TPA via hydrolysis using sulphuric acid has been investigated. The hydrolysis is carried out at a range of acid concentration of 3-15 M, the time period of 3-7 h and temperature range of 130-170°C. TPA was determined by FTIR spectroscopy, elemental analysis and gravimetric calculations. The optimum conditions for maximum PET conversion yield to TPA recovery of 96% are: 12 M H2SO4 at 140^C for 5 h.