VOCs characteristics and their relation with rheological properties of base and modified bitumens at different temperatures

Abstract

During heating process of bituminous materials, volatile organic compounds (VOCs) will be released, and it is harmful to the skin, the respiratory and nervous system of the human body, especially increasing its carcinogenic tendency. In this study, the VOCs emission of base and modified binder was characterized as the function of typical temperatures by gas chromatography coupled with mass spectrometry (GC/MS). The rheological behavior of each binder before and after the emission of VOCs was compared. The relation between the VOCs emission of bitumen and its rheological properties was researched. The results indicated that a higher temperature can lead to increase of VOCs components of binder. The addition of SBS modifier can reduce VOCs components of its base binder. However, the degradation of the SBS modifier decreased its inhibition effect on the VOCs emission of bitumen at 220 °C. Naphthalene release and carcinogenic index of polycyclic aromatic hydrocarbons (PAHs) increased with the increase of temperature. The complex-flow activation energy Ea increased after VOCs emission. Naphthalene content exhibited a better linear relation with Ea.