REACTION OF VISBREAKER BITUMENS WITH SULFUR

The utilization of sulfur in bituminous binders started many years ago : a number of roads were paved in U.S. with SA (sulfur-asphalt) mixtur es. Literature reports that, when mixing sulfur and asphalt, H2S evolu tion starts at temperatures higher than 150 degrees C. By using therma l analysis techniques, the present paper shows that H2S evolution begi ns at about 130 degrees C for most types of bitumens. Kinetics of reac tion between sulfur and visbreaker bitumens were also studied: the rea ction order with respect to sulfur is equal to 0.5 for the three visbr eaker bitumens considered in this work.