Plasmant

On Friday November 8 at 2 p.m., Joachim Slaets from our UAntwerp - Department of Chemistry and supervised by Annemie Bogaerts will publicly defend the PhD thesis "Plasma chemistry modelling for the conversion of CO2 and CH4 into value-added chemicals under atmospheric pressure plasma conditions" at the Campus Drie Eiken, aula O.01. Everyone is cordially invited to attend this public defense. Global CO2 concentrations in the atmosphere have reached unprecedented levels, driven primarily by anthropogenic emissions. This alarming rise in greenhouse gases (GHGs) presents a significant challenge to global climate stability, with CO2 being the primary contributor to climate change. Industrial activities are major sources of these emissions, highlighting the urgent need for innovative and sustainable solutions. Plasma technology emerges as particularly promising, which creates a highly reactive environment through the presence of high-energy electrons. By leveraging such processes, CO2 can be transformed into useful chemicals, contributing to both emissions reduction and resource circularity. One interesting reaction, which can be carried out in a plasma environment, is the dry reforming of methane (DRM), a process that utilizes CO2 and methane (CH4) to produce a mixture of carbon monoxide (CO) and hydrogen (H2). These are valuable intermediates for further chemical synthesis, which can be used to synthesize a variety of chemicals and fuels. Through chemical kinetics modelling a wide range of conditions is explored to better understand the core chemical kinetics of DRM in warm plasma. Thereby examining the performance of the process across a wide temperature range and highlighting the limitations of various gas mixtures. The findings demonstrate where plasma-specific kinetics diverges from thermal gas-phase chemistry, offering new insights into the unique behavior of plasma-driven reactions. Also, the effect of nitrogen (N2) on plasma-based DRM is investigated through computational modelling to support experimental results and demonstrate the role of N2 in the conversion process within a gliding arc plasmatron (GAP) reactor. Revealing a small fraction of N2 can improve the process. Furthermore, after the plasma has converted the gas molecules, further chemical changes can still occur, influencing the overall efficiency and product distribution. The model demonstrates that quenching the gas temperature does not generally improve performance, except in CO2-rich mixtures where certain reactions are influenced by the cooling process, leading to notable changes in the product distribution. The benefits of combining the hot plasma effluent with unconverted gas are also explored, as the residual heat from the plasma can be reused to drive additional reactions, thereby improving the overall efficiency of the process.

On Thursday October 10 at 1:30 p.m., Shangkun Li from our UAntwerp - Department of Chemistry and supervised by Annemie Bogaerts & Erik C. Neyts will publicly defend the PhD thesis "Plasma-driven direct CH4 conversion to high value-added products: experiment and modeling" at the Campus Drie Eiken, aula R2. Everyone is cordially invited to attend this public defense. The direct conversion of CH4 to value-added chemicals has attracted intensive interest from both academic and industrial communities. Plasma technology is a promising approach to activate gas molecules by electricity instead of heat, and it can be operated at mild conditions and allows easy upscaling. The combination of plasma and catalysis often shows synergy. In order to optimise this syngergistic operation, it is important to understand the plasma and plasma-catalyst interactions at a fundamental level. However, it is not straightforward to reveal the entire mechanism because of the intrinsically highly complex reactions of plasma catalysis. This thesis aims to provide a fundamental understanding of plasma-driven direct CH4 conversion into value-added products using various oxidants (i.e., O2, CO2, and H2O), involving plasma gas-phase reactions and plasma-assisted surface reactions on a catalyst by combining experiments and modeling, which could be of great interest for the application of plasma-based gas conversion at a wider scale, boosting the transition towards a more sustainable energy economy.

I am honored that I was recently awarded the Best Student Oral Presentation Award at the 10th International Conference on Plasma Medicine (#ICPM10) in Slovenia, where I presented my experience with how critical comparison between methods can aid in increasing both comparability and understanding of results in our field. As I presented my computational work at a mostly experimental conference, this was especially motivating. I appreciate as well the interesting discussions that followed, and continue to be amazed by the scientific efforts in this field. My thanks goes to both the organizers and my fellow attendees for making this such a fun and interesting experience.