Room Temperature, Ambient Pressure Synthesis of Urea By Electrolysis and Its Accurate and Consistent Measurement

There is rapidly growing interest in the electrochemical reduction of both nitrite and carbon dioxide to mitigate environmental concerns and produce fuels and commodity chemicals (1). Urea is an important target in this area since it is the most widely used nitrogen fertilizer, and can also be used as a fuel and source of hydrogen. It can be produced simultaneously by electrochemical coreduction of NO2 - and CO2 (2-7). Various TiO2 based catalysts such as Cu-doped TiO2 (7) and FeTiO3 (4) have been reported to be effective for co-reduction of CO2 and NO2 -. Metallophthalocyanine catalysts have also been found to be effective in a gas-diffusion electrode configuration under ambient conditions (3). The primary objective of this research is to develop fast and straightforward methodologies that can be routinely used to comprehensively evaluate and compare commercial and new catalysts for co-electrolysis of CO2 and NO2 - in an anion exchange membrane multi-cathode electrolysis cell under ambient conditions. The second objective is using this methodology to synthesize urea and develop reliable and consistent urea measurement methods using various techniques including spectrophotometric, 1H-NMR, mass spectrometry, and enzyme-based methods. It was found that NO2 - and the electrolyte can cause interference during urea measurement. In this research, commercial catalysts such as iron (II) phthalocyanine were used for co-electrolysis of CO2 and NO2 -. Acknowledgements This project is funded in part by the Government of Canada. / Ce projet est financé en partie par le gouvernement du Canada, and by Memorial University References C. Tang, Y. Zheng, M. Jaroniec and S. Z. Qiao, Angew. Chem. Int. Ed., 60, 19572 (2021). M. Shibata, K. Yoshida and N. Furuya, J. Electrochem. Soc., 145, 2348 (1998). M. Shibata and N. Furuya, Electrochim. Acta, 48, 3953 (2003). P. Siva, P. Prabu, M. Selvam, S. Karthik and V. Rajendran, Ionics, 23, 1871 (2017). Y. G. Feng, H. Yang, Y. Zhang, X. Q. Huang, L. G. Li, T. Cheng and Q. Shao, Nano Lett., 20, 8282 (2020). N. N. Meng, Y. M. Huang, Y. Liu, Y. F. Yu and B. Zhang, Cell Reports Physical Science, 2 (2021). N. Cao, Y. L. Quan, A. X. Guan, C. Yang, Y. L. Ji, L. J. Zhang and G. F. Zheng, J. Colloid Interface Sci., 577, 109 (2020).