Knowledge Agora



Similar Articles

Title All Green Microwave Assisted 99% Depolymerisation of Polyethylene Terephthalate into Value Added Products via Glycerol Pre-treatment and Hydrolysis Reaction
ID_Doc 12577
Authors Azeem, M; Attallah, OA; Tas, CE; Fournet, MB
Title All Green Microwave Assisted 99% Depolymerisation of Polyethylene Terephthalate into Value Added Products via Glycerol Pre-treatment and Hydrolysis Reaction
Year 2024
Published Journal Of Polymers And The Environment, 32.0, 1
Abstract Energy-efficient and fast depolymerisation technologies present as new sustainable and green recycling routes for achieving a circular economy for plastics. Herein, we present a highly efficient 2-step microwave-based (MW) degradation of polyethylene terephthalate (PET). Initially, a MW-assisted pre-treatment was evaluated using glycerol as a non-toxic reagent for the conversion of PET into a modified form that makes it easily depolymerised. Box Behnken Design was employed to determine the optimised pre-treatment conditions attaining maximum PET weight loss and favourable crystallinity and carbonyl indices for the pre-treated PET. Glycerol of 12 mL volume and 3 min of 182W MW irradiation resulted in 11% PET weight loss at onset temperature of degradation and gave rise to carbonyl index up to 4.22 and 33% crystallinity of pre-treated PET. MW assisted hydrolysis of the pre-treated PET was then performed in the presence of sodium bicarbonate and ethylene glycol as depolymerizing agents. Within 3 min, the proposed depolymerisation methodology provided 99.9% conversion of PET into 79.1% terephthalic acid (TPA), 17.6% monohydroxyethyl terephthalate (MHET), and 1.8% bis (2-hydroxyethyl) terephthalate (BHET). The obtained TPA was separated from the monomers mixtures and its purification was evaluated via different characterization techniques against a standard TPA. A purity of 95%, 82.4 APHA colour value, 645.3 mgKOH/g acid number and acceptable heavy metal content indicated that the purified TPA can be repolymerised as virgin PET.
PDF

Similar Articles

ID Score Article
14519 Ghosal, K; Nayak, C Recent advances in chemical recycling of polyethylene terephthalate waste into value added products for sustainable coating solutions - hope vs. hype(2022)Materials Advances, 3, 4
10570 Yuan, Z; Yang, JL; Manos, G; Tang, JW Microwave Catalytic Depolymerization of Polyethylene Terephthalate Plastic to the Monomers(2023)Ccs Chemistry, 5, 12
22086 Conroy, S; Zhang, XL Theoretical insights into chemical recycling of polyethylene terephthalate (PET)(2024)
26311 Valh, JV; Voncina, B; Lobnik, A; Zemljic, LF; Skodic, L; Vajnhandl, S Conversion of polyethylene terephthalate to high-quality terephthalic acid by hydrothermal hydrolysis: the study of process parameters(2020)Textile Research Journal, 90, 13-14
28305 Enache, AC; Grecu, I; Samoila, P Polyethylene Terephthalate (PET) Recycled by Catalytic Glycolysis: A Bridge toward Circular Economy Principles(2024)Materials, 17.0, 12
23856 Jeya, G; Dhanalakshmi, R; Anbarasu, M; Vinitha, V; Sivamurugan, V A short review on latest developments in catalytic depolymerization of Poly (ethylene terephathalate) wastes(2022)Journal Of The Indian Chemical Society, 99, 1
14289 Sabde, S; Yadav, GD; Narayan, R Conversion of waste into wealth in chemical recycling of polymers: Hydrolytic depolymerization of polyethylene terephthalate into terephthalic acid and ethylene glycol using phase transfer catalysis(2023)
29189 Babaei, M; Jalilian, M; Shahbaz, K Chemical recycling of Polyethylene terephthalate: A mini-review(2024)Journal Of Environmental Chemical Engineering, 12.0, 3
17139 Unruean, P; Padungros, P; Nomura, K; Kitiyanan, B Efficient chemical depolymerization of polyethylene terephthalate via transesterification with ethanol using CaO catalyst(2024)Journal Of Material Cycles And Waste Management, 26, 2
27476 McNeeley, A; Liu, YA Assessment of PET Depolymerization Processes for Circular Economy. 1. Thermodynamics, Chemistry, Purification, and Process Design(2024)Industrial & Engineering Chemistry Research, 63.0, 8
Scroll