Roles of interactions between aromatic-poor and aromatic-rich fractions on bio-oil upgrading and CO2 fixation during co-electrolysis of bio-oil and CO2

Co-electrolysis of bio-oil (derived from the fast pyrolysis of lignocellulosic biomass) and CO 2 to produce sustainable and carbon-neutral chemicals offers a promising approach for simultaneous bio-oil upgrading and CO 2 fixation. Despite variations in raw materials, bio-oil shares common functional groups, comprising aromatic-poor fractions (APF, mainly from cellulose and hemicellulose) and aromatic-rich fractions (ARF, mainly from lignin), whose interactions significantly influence the electrochemical upgrading of bio-oil. In this study, building on our previously proposed method of co-electrolysis of bio-oil and CO 2 , we further investigated the roles of the interactions between APF and ARF on bio-oil upgrading and CO 2 fixation. Results showed that the interactions suppressed CO 2 fixation, promoted CO 2 conversion, improved product selectivity of organic acids, and inhibited polymerization. Notably, the interactions between acetophenone and ARF significantly enhanced the formation of organic acids, with a 136.55 % increase in their content. Furthermore, the interactions facilitated the conversion of larger molecular compounds (350–450 Da) into smaller molecular compounds (<300 Da) during co-electrolysis of bio-oil and CO 2 . In conclusion, we proposed a mechanism for bio-oil upgrading and CO 2 conversion, influenced by interactions between APF and ARF during the co-electrolysis, providing valuable insights into the synergistic processing of bio-oil from various sources with CO 2 .