In Situ Spectroelectrochemical Study of Acetate Formation by CO 2 Reduction Using Bi Catalyst in Amine-Based Capture Solution.

Carbon capture and utilization (CCU) are technologies sought to reduce the level of CO 2 in the atmosphere. Industrial carbon capture is associated with energetic penalty, thus there is an opportunity to research alternatives. In this work, spectroelectrochemistry was used to analyze the electrochemical CO 2 reduction (eCO 2 R) in CO 2 saturated monoethanolamine (MEA)-based capture solutions, in a novel CCU process. The in situ Fourier transform infrared (FTIR) spectroscopy experiments show that at the Bi catalyst, the active species involved in the eCO 2 R is the dissolved CO 2 in solution, and not carbamate. In addition, the products of eCO 2 R were evaluated under flow, using commercial Bi 2 O 3 NP as catalyst. Formate and acetate were detected, with normalized FE for acetate up to 14.5 %, a remarkable result, considering the catalyst used. Acetate is formed either in the presence of cetrimonium bromide (CTAB) as surfactant or at higher current density (>-100 mA cm -2 ) and the results enabled the proposition of a pathway for its production. This work sheds light on the complex reaction environment of a capture medium electrolyte and is thus relevant for an improved understanding of the conversion of CO 2 into value-added products and to evaluate the feasibility of a combined CCU approach.