Effect of nano Ni–Fe alloy addition on flash pyrolysis of poly(ethylene glycol)

Flash pyrolysis of p-PEG (pure PEG) and PEG/NiFe (mixture of PEG and nano Ni–Fe alloy) was carried out in argon atmosphere, aiming to study the effect of nano Ni–Fe alloy on the behavior and mechanism of PEG pyrolysis. A special combinational system was designed to perform pyrolysis experiment and collect pyrolysis products, while GC/MS was employed to identify the products. The experimental results showed that nano Ni–Fe alloy changed not only the relative contents but also the series of PEG pyrolysis products. It was interesting that all of 15 possible series of PEG pyrolysis products in theory were detected from p-PEG and/or PEG/NiFe pyrolysis in the present work. Six product series disappeared and two new product series were detected after adding nano Ni–Fe alloy. Based on quantitative analysis of the end groups of products, the effect of nano Ni–Fe alloy on PEG pyrolysis process as well as the mechanism was discussed. Ni and Fe played quite different roles in the process of PEG pyrolysis. Fe made end group OCH2CH3, OCHCH2, OH and OCH3 transfer to OCH2CHO by inducing hydrogen transfer and OC bond cleavage; Ni made OCHCH2 transfer to OCH2CH3 by inducing hydrogenation.