CHARACTERISATIONS OF BIO-ASPHALT INCORPORATING PALM BIO-OIL FROM WASTE EMPTY FRUIT BUNCHES

Abstract

Bio-asphalts feature economic, social, and environmental benefits and may thus be potentially substituted for petroleum-based asphalt in asphaltic concrete mixtures. This article presents the experimental investigation of adding palm bio-oil derived from empty fruit bunches (WBO) into the conventional asphalt binder at 5, 10 and 15 wt%. The physical properties of bio-asphalt were assessed via the penetration, softening point, rotational viscosity, ductility, and mass loss after the rolling thin-film oven (RTFO) tests. Fourier-transform infrared spectroscopy (FTIR) and gas chromatography-mass spectrometry (GC-MS) tests were used to identify the chemical composition and functional groups of the bio-oil and bio-asphalt samples. The binder coatability was assessed by static water immersion and water boiling tests. The addition of bio-oil lowers the softening point and viscosity of the binder while increasing its penetration, ductility and mass loss after RTFO. The main absorption peaks for WBO bio-oil and WBO bio-asphalts were corresponding to C=H stretching of alkanes and aliphatic compounds, respectively. The bio-oil was mostly composed of aromatic and oxygenated compounds, as observed from GC-MS results, which justified the FTIR analysis for WBO bio-oil. The addition of WBO bio-oil improved the bonding characteristics of asphalt-aggregates, indicating that it has a significant potential for use in the production of bio-asphalt.