Interaction of Nitrogen and Sulfur Species with Oxygen Carriers in Chemical Looping with Oxygen Uncoupling

化学环是一种很有前途的碳捕获策略。在化学环氧解耦（CLOU）过程中，燃烧过程所需的氧气从称为氧载体的金属氧化物中释放出来，消除了空气和燃料之间的直接接触，使二氧化碳容易分离。本研究的目的是利用各种实验技术和分子模型来研究氮和硫与氧载体材料的相互作用。这项研究将对未来将要建造的化学环工厂产生影响，因为它将对CLOU过程中污染物的形成提供一个基本的了解。如果在根据排放水平和法规进行固存之前需要对二氧化碳流进行处理，这种理解将有助于设计排放控制技术。从这个项目中产生的实验数据将深入了解这些污染物对氧载体活性的影响，这将有助于设计未来的氧载体材料，这些材料将持续许多氧化还原循环，从而降低材料的成本。在发现适合于化学环应用的氧载体材料方面已经付出了很大的努力；然而，对氧载体表面发生的非均相化学反应，特别是与杂质的相互作用，缺乏基本的认识。在提出的工作中，铜和锰基氧载体和支撑材料的各种组合将在CLOU条件下进行测试，同时暴露于氮和硫物种，以揭示在氧载体表面发生的非均相反应。氧载体表面也将模拟使用密度泛函理论和反应途径将确定。通过采用实验规模的实验和理论模拟，该项目将提供对CLOU过程中特定的NOx（氮氧化物）和SOx（硫氧化物）形成机制的基本理解。

1606874 - PadakChemical looping is one of the promising strategies for carbon capture. In the chemical looping oxygen uncoupling (CLOU) process, the oxygen necessary for the combustion process is released from a metal oxide, called the oxygen carrier, eliminating the direct contact between air and fuel, causing carbon dioxide to be easily separated. The objective of the proposed work is to investigate the interaction of nitrogen and sulfur species with the oxygen carrier material employing various experimental techniques as well as molecular modeling. This research will create an impact on the chemical looping plants that will be built in the future, in the sense that it will provide a fundamental understanding of the pollutant formation during the CLOU process. This understanding would aid in the design of emission control technologies, if a treatment of the carbon dioxide stream is required prior to sequestration depending on the emission levels and regulations. Experimental data that will be produced from this project will provide insight into the effect of such pollutants on the activity of the oxygen carrier, which would help the design of future oxygen carrier materials that would last for many oxidation reduction cycles, thus reducing the cost of the materials.There has been a great effort in the discovery of oxygen carrier materials that are suitable for chemical looping applications; however, there is a lack of a fundamental understanding of the heterogeneous chemistry occurring on the oxygen carrier surface, especially for the interactions with impurities. In the proposed work, various combinations of copper and manganese-based oxygen carrier and support materials will be tested under CLOU conditions while being exposed to nitrogen and sulfur species to shed light into the heterogeneous reactions taking place on the oxygen carrier surface. The oxygen carrier surfaces will also be simulated using density functional theory and the reaction pathways will be determined. By employing bench-scale experiments and theoretical simulations, this project will provide a fundamental understanding of NOx (nitrogen oxides) and SOx (sulfur oxides) formation mechanisms specific to the CLOU process.