Abstract : In this dissertation, we present a temperature-dependent plasma-chemical kinetic study to investigate the roles of both electron-induced and thermally induced reactions in the decomposition of NH3, ultimately providing valuable insights for process optimization. To this end, we conducted experiments and numerical simulations across a wide range of operational parameters. A temperature-controlled dielectric barrier discharge reactor was introduced for experimental investigations and a plasma-chemical kinetic model (KAUSTKin) was employed for numerical analysis with the developed plasma-chemical reaction mechanism. As a result, we discovered the non-monotonic effects of operating parameters (i.e., gas temperature, NH3 concentration, discharge power, reduced electric field). Furthermore, the primary kinetics in the plasma-induced cracking of NH3 was also revealed: (i) 13 major reactions and their reaction pathways were identified, explaining the underlying chemistry for non-monotonic conversion trends; and (ii) the key recombination (NH2+H+M ↔ NH3+M) appeared as the most important rate-limiting step. We believe that the present dissertation will spark fundamental interest in plasma-induced NH3 cracking technology and contribute to technical advancements.
Bio : Seunghwan Bang is a Ph.D. candidate in Mechanical engineering program under the supervision of Professor Min Suk Cha. He obtained his bachelor's and master’s degree in mechanical engineering from Yeungnam University, South Korea, in 2018. His Ph.D. research focus on the development of a comprehensive reaction mechanism for achieving the fundamental understanding of the plasma-induced chemical process, particularly for NH3 cracking process.