Recycling

Biography

Biography: Norgbey Eyram

Abstract

Concerns on the cost, over security of supply, and environmental impact of using petroleum-based materials have led to the modification and development of alternative asphalt binders for flexible pavements. The objective of this study is to investigate the thermal properties and the uniform miscibility of Kraft Lignin and petroleum asphalt blends using the thermogravimetric analysis (TGA), differential scanning calorimetry (DSC), scanning electron microscopy (SEM) and Fourier transform infrared spectroscopy (FT-IR) over the entire range of composition. The study shows that 30% by weight of lignin can be added to asphalt to obtain uniformly mixed and a thermally stable binder composite. Lignin has a lower Td value than asphalt. An increase in the concentration of lignin in the composite reduces the Td value of the composite making the composite less thermally stable. The lowest Td value of the composite binder recorded was 280 °C while the mixing temperature of bitumen and aggregate is 165 °C. Thus, the addition of 30% had no negative results on the thermal stability of the composite. The thermal behaviour of these blends as measured by TGA suggests compatibility for the blends containing up to 30% (weight) of Kraft lignin. SEM results showed a uniform distribution of lignin of particle size less than 75µm in the bitumen. The infrared data show that the miscibility of the blends with varying concentrations was a physical reaction since the functional groups in both Lignin and bitumen remained intact in the composite. The thermal stability and the uniform distribution of lignin fibers in asphalt binder gives a positive indication that the composite can be used in asphalt pavements. Not only is the petroleum resource saved and the environment protected but there is an effective use of the solid waste material, lignin.