Synthesis and Characterization of Bio-pitch from Bio-oil

Coal-tar-pitch (CTP) is a fossil carbon material, currently used as a the binder in carbon anode manufacturing process. Regardless of the technical benefits of coal-tar-pitch, it contains polycyclic aromatic hydrocarbons (PAHs), known to be carcinogenic for humans and detrimental to the environment. To overcome this challenge, research was carried out to search for a suitable substitution with health- and environmental-friendly properties. Bio-pitch, produced from bio-oil, could be a potential alternative binder for the carbon anode manufacturing process, due to its similarity with CTP. However, the properties of bio-pitch could be significantly different from those of CTP depending on its origins and process conditions. This study focuses on the synthesis of bio-pitches from bio-oil under different vacuum extraction conditions and characterization of its physical and chemical properties, aiming at the determination of the conditions that may result in suitable properties for anode formulation. Both typical characterization and profound chemical analysis of bio-pitches were carried out, including the determination of density, softening point, coking value, quinoline insolubles, PAH content, molecular weight, viscosity, and elemental composition and the identification of chemical structures. In addition, the condensed fraction produced was also analyzed to identify the reaction mechanisms occurring during the pyrolysis process.