Glycolysis of postconsumer polyethylene terephthalate waste

Abstract Glycolytic depolymerization of polyethylene terephthalate (PET) bottle waste was attempted using ethylene glycol (EG) in the presence of chlorides of zinc, lithium, didymium, magnesium, and iron as catalysts. Virtual monomer bis (2‐hydroxyethyl terephthalate) (BHET) was obtained in all cases with nearly 74% yield, the highest yield being achieved with zinc chloride catalyst 0.5% w/w, PET : EG ratio 1 : 14 and 8 h under reflux conditions. The results were comparable to other catalysts like common alkalis, acids, and salts of some earth metals and zeolites used earlier although parameters of glycolysis were observed to vary depending on the catalyst. © 2009 Wiley Periodicals, Inc. J Appl Polym Sci, 2010