Polymerization during low-temperature electrochemical upgrading of bio-oil: Effects of interactions among bio-oil fractions.

The electrochemical method is becoming a promising approach to deliver the bio-oil upgrading objective at room temperature. However, it still faces the coke formation issue because of the easy polymerization nature of bio-oil. Interactions among components impact the polymerization during the electrochemical upgrading of bio-oil. This study investigates the effects of interactions between the aromatic-rich and aromatic-poor fractions (ARFs and APFs) of the bio-oil on polymerization under various reaction time and current densities. Coke yield differences provide direct evidence of the existence of interactions between ARFs and APFs during the electrochemical upgrading process. Our results indicate that the coke yields and its condensation level are decreased by the interactions. The surface area, pore volume and the functionalities content of the coke are increased by the interactions. In addition to polymerization, more types of reactions including hydrogenation and esterification are induced by the interactions, resulting in more types of products and less coke. The interactions can inhibit polymerization by consuming the coke precursors before their condensation. The interactions can also inhibit the anodic adsorption and oxidation, thus depressing polymerization and coke formation. Investigating the impacts of interactions between aromatic-rich and aromatic-poor fractions on polymerization of bio-oil in chronoamperometric electrochemical upgrading. [Display omitted] • Interactions of aromatic-rich and -poor fractions in bio-oil is proven existed in electrolysis. • Aromatic-poor fractions end-cap the reactive chains of polymerization precursors. • Interactions weaken the anodic adsorption and polymerization of bio-oil. • Interactions decrease the yields, surface areas and pore volumes of the coke. [ABSTRACT FROM AUTHOR]