of SO2 (a) and H2S (b) during pyrolysis of waste rubber modified
by woody biomass are illustrated in Fig. 4. As shown in Fig. 4, during
the pyrolysis process, no matter with or without sawdust, sulfur
was always released as a form of SO2. A small amount of H2S
was observed during pure rubber pyrolysis, while no H2S was
found after adding sawdust. It was suggested that the sulfur was
released as a form of SO2 vapor during the pyrolysis.