ISSN print edition: 0366-6352 ISSN electronic edition: 1336-9075 Registr. No.: MK SR 9/7 Published monthly

A kinetic study on the depolymerization of polyethylene terephthalate waste with crude glycerol

Georgy V. Dzhabarov, Valentin N. Sapunov, Violetta V. Shadrina, Mikhail S. Voronov, Tran Diem Nhi, and Dmitry V. Staroverov

D. Mendeleev University of Chemical Technology of Russia, Moscow, Russia

E-mail: ricaura@yandex.ru

Received: 21 December 2020  Accepted: 6 July 2021

Abstract:

The crude glycerol is the main by-product of biodiesel production and contains large amounts of potassium (or sodium) soap. These alkaline compounds may be reacted with ester groups of polyethylene terephthalate (PET) to form the corresponding terephthalic acid salts. In this work, the process of PET depolymerization with crude glycerol with a high content of potassium salts was studied. Depolymerization is the multistage process and proceeds through the formation of oligomers of various molecular weights. Subsequently, the resulting intermediate compounds decompose to low molecular weight oligomers (dimers and trimers), up to dipotassium terephthalate (DPT). A general reaction scheme and a mathematical model of the process are represented, and rate constants of all reactions are estimated.

Keywords: Depolymerization; Waste PET; Recycling; Crude glycerol; Kinetics; Green chemistry

Full paper is available at www.springerlink.com.

DOI: 10.1007/s11696-021-01780-y

Chemical Papers 75 (11) 6035–6046 (2021)