Kinetic, products distribution, and mechanism analysis for the pyrolysis of polyglycolic acid toward carbon cycle. (1st February 2023)

• Record Type: Journal Article
• Authors: Li, Chenyang; Meng, Xin; Gong, Weiguang; Chen, Shiyuan; Xin, Zhong
• Is Part Of: Fuel. Volume 333(2023)Part 2
• Publication Date: 2023-02-01
• Subjects: Polyglycolic acid -- Pyrolysis -- Kinetic -- Product distribution -- Reaction pathway -- ReaxFF-MD; Fuel -- Periodicals; Coal -- Periodicals; Coal; Fuel; Periodicals; 662.6
• DOI: 10.1016/j.fuel.2022.126567
• Languages: English
• ISSNs: 0016-2361

Abstract

Graphical abstract: Highlights: Thermokinetic study for polyglycolic acid (PGA) was carried out. Carbon monoxide, carbon dioxide, and formaldehyde were determined as major gaseous products in the pyrolysis process of PGA by TG-IR and TG-MS systems. Effect of pyrolysis temperature on products was investigated by Py-GC/MS system. The pyrolysis of PGA was initiated by alkoxy bond, followed by acyloxy bond and CC bond. ReaxFF-MD simulation revealed reasonable and new pyrolysis reactions of PGA. Abstract: Present investigation was aimed at exploring the pyrolysis kinetics, product distribution, and mechanisms of polyglycolic acid (PGA) via experiments and reactive force field molecular dynamic (ReaxFF-MD) simulations to establish a foundation for the recycling of raw materials in the future. The kinetic analysis presented that the PGA pyrolysis belonged to the contracting cylinder model with the apparent activation energy ranged from 138.1 to 141.7 kJ/mol. The gaseous product was determined to contain carbon dioxide, carbon monoxide, and formaldehyde through TG-IR and TG-MS, and Py-GC/MS results showed that the yield of glycolide reached the maximum at 450 °C. The ReaxFF-MD simulation revealed that the initial pyrolysis pathway for PGA was the cleavage of alkoxy bond, followed by CC bond and acyloxy bond with the generation of carbon dioxide, carbon monoxide, formaldehyde, and ethenone. This study would provide comprehensive experiment data and meaningful guidance for recycling PGA to achieve a closed-loop economy.