Study on the effect of different aldehyde modifiers on the fume suppression effect, mechanism and road performance of SBS modified asphalt

Sci Total Environ. 2024 Feb 20:912:169162. doi: 10.1016/j.scitotenv.2023.169162. Epub 2023 Dec 9.

Abstract

In order to curb asphalt fume emissions during the heating process of styrene-butadiene-styrene (SBS) asphalt, three aldehyde modifiers [vanillin (X), citral (N) and amyl cinnamaldehyde (J)] were blended into SBS-modified asphalt to prepare aldehyde-modified asphalt in this paper. By collecting solid particles and volatile organic compounds (VOCs) in asphalt fumes to conduct relevant experiments, we have analyzed the fume suppression effect and suppression mechanism of aldehyde modified asphalt, and finally examined the road performance of aldehyde modifiers with the best fume suppression effect. It was found that the average VOCs concentration of aldehyde modified asphalt was reduced by about 78 % after 30 min. Aldehyde modifiers significantly reduce the compositional type and content of VOCs in SBS asphalt and reduce the risk of carcinogenicity by curbing the emission of substances such as benzene and phenol. J asphalt reduced solid particle emissions from SBS asphalt fume by 31.4 % and outperformed both X and N asphalt in inhibiting the escape of solid particulate matter and carcinogens from asphalt fume. Polymer networks and the cross-linking of chemical molecules are the main reasons for inhibiting the escape of asphalt fume molecules. In addition, the J modifier enhanced the high-temperature stabilization and water-stability properties of asphalt mixtures, but slightly reduced the low-temperature cracking resistance. The results showed that the three aldehyde modifiers were effective in inhibiting the volatilization of fumes from SBS modified asphalt. Among them, with the best effect of curbing fume emissions and a better road performance, J-modified asphalt is promising for the application in asphalt fume prevention and emissions reduction, and provides a new solution to reduce construction pollution and physical harm caused by asphalt fume in the construction process.

Keywords: Aldehyde modifier; Asphalt fume suppression; Mechanistic study; Road performance; SBS modified asphalt; VOCs.