Pyrolysis Products of Untreated and Flame Retardant Treated Alpha-Cellulose and Levoglucosan

摘要

A typical gas chromatogram of the volatile pyrolysis products (molecular weights less than 150) of untreated alpha-cellulose contains 39 peaks, however, mass spectral data indicate that at least 59 compounds are present. Since the initial pyrolysis products undergo decomposition, both initial and subsequent decomposition products are included in the analysis. A comparison of the products generated in the temperature range 330 - 400C indicates that the formation of pyrolysis products is essentially independent of temperature. In general, flame retardant treated samples produce fewer products than untreated samples, although the compounds that are present are the same. Some treatments, including 4% iodination, 6% benzhydrylation, and 4% iodination-5% benzhydrylation yield only five prominent compounds: water, acetic acid, furfural, 5-methyl-2-furfuraldehyde, and an unknown. Flame retardant concentration seems to affect the formation of products more than the type of retardant. Comparisons of the chromatograms obtained for untreated levoglucosan and cellulose indicate that most of the decomposition of cellulose probably forms levoglucosan which then decomposes to yield the observed pyrolysis products. (Author)