Research on the preparation of high softening point asphalt from ethylene tar

Ethylene tar was utilized as the raw material to prepare high softening point asphalt via the air oxidation method. The influence of reaction temperature on the properties of the reaction product was systematically investigated. An appropriate reaction temperature enables oxygen elements to incorporate into the asphalt in the form of hydroxyl and carbonyl groups, as well as other structures, thereby forming a cross-linked network and effectively increasing the molecular weight. Additionally, dehydrogenation and ring formation reactions occur under oxidative conditions. As the reaction progresses, the proportion of polycyclic aromatic structures gradually increases. The unsaturated structures formed through dehydrogenation reactions impart high aromaticity to the resulting asphalt, which has a high softening point after complete response. Experimental results indicate that high softening point asphalt with a coke value of 70.3% and a softening point of 265°C can be obtained at a reaction temperature of 330°C and a reaction time of 8 hours.