Catalytic conversion of NaHCO3 into formic acid in mild hydrothermal conditions for CO2 utilization

Highly efficient water splitting and carbon dioxide reduction into formic acid with iron and copper powder

“…In this study, NaHCO 3 was used as the source of CO 2 to simplify the operation and to allow for an accurate quantification of CO 2 [15]. The reagents NaHCO 3 powder (99.5%), Fe powder (200-mesh, 98%) and Cu powder (200-mesh, 99.7%) were purchased from Sinopharm Chemical Reagent Co. Ltd, China.…”

“…However, previous research on the reduction of CO 2 with Fe as a reductant showed that the formic acid production was very low (below 10%) without the addition of catalyst [15]. Therefore, further research with the use of catalyst is required to improve efficient reduction of CO 2 .…”

“…Thus, our research interest focused on the development of cheap and highly active metal catalyst. Among candidate cheap metals catalysts, Ni exhibited a lower catalytic activity in hydrothermal reduction of CO 2 into formic acid with Fe [17] and the formic acid production was limited to only about 16% [15]. Then, we turned our attention to the next candidate of cheap metal Cu, because the study on the activity of Cu for catalyzing CO 2 reduction is limited.…”

“…With this in mind, we previously investigated the dissociation of H 2 O for reducing CO 2 (or NaHCO 3 as a CO 2 source) to formic acid with metallic iron (Fe) as a reductant in the presence or absence of a nickel (Ni) catalyst [15,16]. In this process with Fe, water is used as a source of hydrogen and Fe is used as the reductant for rapidly producing hydrogen, which then is used to reduce the CO 2 in-situ.…”

Pd/C-catalyzed reduction of NaHCO 3 into CH 3 COOH with water as a hydrogen source

“…To further examine the above proposed reaction mechanism, the adsorption enthalpies of the intermediate of formate on the Pd, Cu and Ni were compared by referring the data from literature, and our previous research, in which the HCO 3 − was mainly reduced into C 1 products when Cu or Ni as the catalyst [18,20,33]. It has been reported that the formate adsorption enthalpy on the Pd, Cu and Ni follows the order of Cu (110) < Pd (110) < Ni (110) [35], which suggest that the formate adsorption enthalpy on Cu is the lowest, that is Cu can catalyze the HCOOH formation effectively.…”