Spatially-resolved gas concentration, surface species and temperature measurement for heterogeneous catalyzed reactions using an optical accessible channel reactor.

新的原料和材料被引入能源和化学工业。催化剂的使用是开发环境友好和经济可行的转化过程(例如，生物质、废物和二氧化碳转化为燃料和化学品)的关键。反应器工程研究、催化剂设计和对反应机理的了解，不仅对优化产品产率，而且对管理热量需求具有重要意义。对这些催化反应建模是有利的，因为它允许容易和经济有效地研究操作条件对反应器和整个过程性能的影响。只有当化学反应器中的所有相关过程及其相互作用都得到充分的表示时，才能得到一个好的模型。为此，只需从实验中获得准确的动力学模型是必要的。**通常使用带有数百毫克催化剂的小型实验室反应堆，其中气体成分仅在反应器出口处测量。因此，一个单一的实验产生一个单一的数据点。为了避免因反应性质而引起的温度变化过大，使用了高度稀释的混合气体(&gt；90%的惰性气体)、稀释的催化剂床，并且反应器在低转化率(&lt；10%)下运行。这些实验条件可能远离工业相关环境。**拟议研究的目的是开发创新的仪器工具和实验方法，以建立和评估可持续能源转换领域中催化反应网络的复杂动力学模型。具体地说，我计划开发空间分辨率测量技术，允许收集关于气体组成、催化剂表面物种和沿反应堆轴线的温度分布的信息。通过这样做，可以更详细地研究反应动力学、反应机理和转移现象。在这个研究项目中，将研究生物质生产合成天然气(SNG)的反应网络。生物质通过气化、气体净化、催化甲烷化和燃料升级的热化学转化为SNG的过程再次变得突出。它可以将以固体碳形式束缚的化学能转化为气体产品，可以很容易地在现有的天然气管道中运输。从理论上讲，Bio-SNG可以提供加拿大当前天然气需求的60%，这使得这一过程对我们的国内能源市场非常有趣。*该反应网络的动力学数据将在新设计的光学可接近的催化板反应器中实验获得。板式反应器的底部涂有一层薄薄的催化剂层。反应器的顶部用一个特殊设计的玻璃窗关闭，通过这个玻璃窗用红外热像仪测量催化剂表面的温度分布。气体组成的空间分辨测量是用可移动的细毛细管进行的，空间分辨率高达~200微米，因此一次实验就有大量的数据点。两个空间位置之间的浓度差是有差别的，但可以实现完全转换。用红外光谱(FTIR)测定了催化剂沿反应器轴线的表面物种。**所开发的工具还可用于研究其他催化反应，如减少汽车行业的NOx排放。这项工作的最终结果将是通过综合实验观察和理论建模相结合的方式加深对催化反应机理的理解，并培训人员(4名研究生和5名本科生)。

New feedstocks and materials are introduced into the energy and chemical industries. The use of a catalyst is key to the development of environmentally friendly and economically feasible conversion processes (e.g. biomass, waste, and CO2 into fuels and chemicals). Reactor engineering research, catalysts design and understanding of the reaction mechanisms are of primary importance in optimizing not only product yields but also managing heat requirements. Modeling these catalyzed reactions is advantageous as it allows to easily and cost effective study the influence of operating conditions on the reactor and overall process performance. A good model can only be obtained if all relevant processes in a chemical reactor and their interactions are represented adequately. For this, accurate kinetic models are necessary that are obtained from experiments only.**Usually small laboratory reactors with a few hundred milligram of catalyst are used in which the gas compositions are measured at the reactor exit only. Thus, a single experiment results in a single data point. To avoid excessive temperature changes due to the nature of the reactions, highly diluted gas mixtures (>90% inert gas), diluted catalyst beds are used, and the reactor is operated at low conversion (<10%). These experimental conditions might be far away from industrial relevant settings.**The aim of the proposed research is the development of innovative instrumentation tools and experimental methodologies to build and evaluate sophisticated kinetics models for catalyzed reaction networks in the field of sustainable energy conversion. In detail, I plan to develop spatially-resolved measurement techniques that allows gathering information on gas composition, catalyst surface species and temperature profiles along the reactor axis. By doing so reaction kinetics, reaction mechanisms and transfer phenomena can be investigated in much more detail. Within this research program the reaction network of the production of synthetic natural gas (SNG) from biomass will be studied. The thermochemical conversion of biomass to SNG via gasification, gas cleaning, catalytic methanation and fuel upgrading is a process that has again become prominent. It allows to convert the chemical energy bound in a solid carbon form into a gaseous product, which can be easily transported in already existing natural gas pipelines. Bio-SNG could theoretically provide up to 60% of current natural gas demand in Canada, which makes this process very interesting for our domestic energy market.*The kinetic data for this reaction network, will be experimentally obtained in a newly designed optically accessible catalytic plate reactor. The bottom of the plate reactor is coated with a thin catalyst layer. The top of the reactor is closed with a special designed glass window through which the catalyst surface temperature profile is measured by means of infrared thermography. Spatially-resolved measurement of the gas composition is carried out with a thin movable sampling capillary achieving a high spatial resolution of ~200 µm, and thus a large number of data points for a single experiment. The concentration difference between two spatial positions is differential, but complete conversion can be achieve. Catalyst surface species along the reactor axis are measured by means of infrared spectroscopy (FTIR). **The developed tools can also be applied to investigate other catalyzed reactions such as reduction of NOx emissions in the automotive industry. The net result of this work will be a deeper understanding of catalyzed reaction mechanisms through the combination of comprehensive experimental observation and theoretical modeling, and trained personnel (4 graduate and 5 undergraduate students).