Pyrolysis of furan and its derivatives at 1100 °C: PAH products and DFT study

•The pyrolysis of furan, 2-methylfuran, furfuryl alcohol, and furfural have been investigated by Py-GC–MS at 1100 °C.•Different side chain functional groups on furan-rings lead to different kinds of products and product distributions.•Mechanism for furan-ring opening and decomposition is universal for furans.•Formation of benzene from furan has been calculated by B3LYP/6-31G + +(d,p)

In this work, the pyrolysis of furans (furan, 2-methylfuran, furfuryl alcohol, and furfural) have been checked by Py-GC–MS at 1100 °C to detect the decomposition of furans and the formation of benzene derivatives and PAH. From the Py-GC–MS results, different side chain functional groups on furan-ring lead to different kinds of products and product distributions, such as hydroxyl group leading to dimers, and aldehyde group leading to pyrans, but the mechanism for furan-ring opening and decomposition is universal for furans pyrolyzed in this study. In order to explain the experimental results and the formation of benzene derivatives and PAH, the formation of benzene from furan has also been calculated by B3LYP/6-31G + +(d,p). Two possible benzene formation mechanisms, Diels-Alder and acetylene reaction mechanism, have been proposed and calculated. By comparison, it has been regarded that Diels-Alder reaction was more possible for PAH formation as this mechanism has a lower activation energy for initiation step, but acetylene reaction mechanism was more possible for benzene formation as this mechanism has a lower global activation energy.