| Biography | |
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 Dr. Marek Wiśniewski Nicolaus Copernicus University in Toruń, Poland |
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| Title: Glowing gases for green chemistry – mechanistic viewpoint of catalytic processes under non-thermal plasma | |
| Abstract: The low temperature plasmas are extremely complex systems and processes being performed under these conditions usually involve a “great zoo” of different charged and uncharged species which can all contribute to the properties of the resulting products. Despite great advancements in the field of plasma based processes, the details involved in this “plasma production process” are still far from being understood. The non-thermal plasmas are nowadays widely used for a variety of different applications ranging from the VOC removal, CO2 reduction, etching of microstructures and the deposition of thin films to the modification of surfaces and the synthesis of novel materials. The flexibility of plasma based processes and in particular the possibility to combine different kinds of plasma based processes make them an ideal tool for the fabrication of nanocomposite materials and catalysts. On the other hand we can observe the “water paradox” – our planet is full of this compound, however drinking water starts to be rare. Thus we need to start use water (not-tap-water) as a reagent. New technologies treating water as a source of hydrogen are required. Also, the "Oil Crisis" has stimulated research on new energy sources as substitutes for fossil fuel. Hydrogen is an excellent energy source and one of the most important raw materials, used in large scale in many industrial processes such as ammonia synthesis, methanol synthesis, CO hydrogenation, metallurgy, and many petrochemical reactions. Current methods for hydrogen production still include steam reforming of methane, the water gas shift reaction, and electrolysis of water. H2O splitting (actually co-splitting) is the key step of reactions utilized in many environmental-friendly processes. Two most important are: so called "artificial photosynthesis" (CO2/H2O), "nitrogen fixation" (N2/H2O). However, there are some inconveniences: water molecules are very stable. Their decomposition is a strongly endothermic reaction (AG° = 229 kJ/mol). Thus, external energy such as thermal, light, or electric energy are needed. Low temperature plasma (LTP) can perfectly function as sources of energy suitable for water splitting, thus solving the catalysis society challenge: the production of hydrocarbons from water and CO2 in low energy consumption systems. Also, the N2 fixation reaction is one of the most important chemical processes in nature as it is essential for both human beings and the planet’s ecosystem. NH3 is the main product of N2 fixation and nowadays is the most widely produced chemical, with an annual production of over 200 million tons. Nearly 80% of synthetic NH3 is consumed as a raw material in industry for the synthesis of fertilizers. The main objective of the presentation will be to answer the questions: (i) is it possible to control the overall catalytic activity and selectivity to most wanted product: hydrogen, hydrocarbons, ammonia, urea?; (ii) how the main parameters affected the mechanism of the process?; (iii) are surface structures, in form of: C=O, C–O, and C–OH for CO2/H2O, and C=N, C–N and –NCO (–CNO), when N2 is incorporated into the reaction zone, the main intermediates of the processes? Acknowledgements: The author gratefully acknowledge financial support by the Excellence Initiative – Research University program of Nicolaus Copernicus University, grant: IDUB-2323. | |
| Biography: Marek Wiśniewski has completed his PhD from Nicolaus Copernicus University in Toruń, Poland and postdoctoral fellow from Claude Barnard University in Lyon, France. He is the member of Chair of Materials Chemistry, Adsorption and Catalysis, and Physicochemistry of Carbon Materials Research Group. He has published over 80 scientific papers in reputed journals. He is interested in synthesis of novel catalysts including carbon materials and MOF structures and their unusual properties studies. Moreover, for a few years he works with low temperature plasma. He built some glow discharge reactors for in-situ investigations. | |
