Abstract

The widespread commercial application of wax has resulted in the generation of significant volumes of waste waxes. Pyrolysis is a highly viable method for recycling waste hydrocarbons. In this study, pyrolysis behaviors of saturated hydrocarbons with molecular weights < 800 g mol–1 were investigated based on molecular weight and pyrolysis temperature (423°C, 500°C, 590°C, 670°C, and 764°C). Additionally, pyrolysis products were analyzed using gas chromatography/mass spectrometry . The major pyrolysis products were alkanes, alkenes, and alkadienes. The dominant pyrolysis product—determined by the maximum peak area—depended significantly on both molecular weight and pyrolysis temperature. Alkenes were more abundant than the other products, whereas small alkadienes were rarely generated. The quantities of the pyrolysis products increased with the molecular weight of the sample. The appropriate pyrolysis temperatures for generating alkanes and alkadienes were approximately 590°C and 670°C, respectively, whereas those for generating alkenes decreased as the molecular weight of the sample increased. The dissociation energies of C–C bonds in the saturated hydrocarbon chains were calculated to discuss the experimental results. Olefins derived from pyrolysis can be used as reactants in chemical synthesis.

Keywords: saturated hydrocarbon waste, pyrolysis, gas chromatography/mass spectrometry, alkanes, alkenes, alkadienes