Hydrochar from corn stalk used as bio-asphalt modifier: High-temperature performance improvement

Biomass utilization, even for conversion products like hydrochar or biochar, has an increasing demand because improper disposal can cause intensive pollution. In this study, hydrochar obtained by hydrothermal treatment of corn stalk was added to virgin asphalt as a novel modifier by manual stirring and high-speed shearing. This hydrochar-modified asphalt (HCMA) showed a better high-temperature performance compared to unmodified asphalt, and the optimized dosage was 6 wt% with Rutting Index reaching 76 degrees C, and its penetration and softening point reaching 31.70 (0.1 mm) and 54.70 degrees C, respectively. The macroscopic representation of modified asphalt was conducted by microscopic characterization methods such as Fourier Transform Infrared Spectroscopy (FTIR) and Gel Permeation Chromatography (GPC). It was demonstrated that the performance was improved by the good blending state between hydrochar and asphalt. The application of hydrochar in modifying asphalt can reduce pollution and enhance its high-temperature performance, which has a potentially extensive application prospect in pavement engineering in subtropical and tropical climate.

Automated summary

Hydrochar obtained by hydrothermal treatment of corn stalk can be used as a modifier to improve the high-temperature performance of asphalt and reduce pollution, showing potential extensive application prospect in subtropical and tropical climate for pavement engineering.