{"title":"Modeling nitrogen species from ammonia reciprocating engine combustion in temperature-equivalence ratio space","authors":"William F. Northrop","doi":"10.1016/j.jaecs.2023.100245","DOIUrl":"10.1016/j.jaecs.2023.100245","url":null,"abstract":"<div><p>This paper explores nitrogen species formation in temperature (T)-equivalence ratio (ϕ) space under internal combustion engine-relevant conditions using zero-dimensional modeling. The analysis reveals that N<sub>2</sub>O and NO are formed in a much larger region of ϕ-T space than in hydrocarbon combustion due to fuel chemical pathways. N<sub>2</sub>O is formed over a large range of ϕ, primarily in low temperature regions that have significant levels of unburned NH<sub>3</sub>. NO is formed over a large, high temperature, lean region. Further analysis shows that even when mixing burned gas with unburned NH<sub>3</sub> from engine crevices, N<sub>2</sub>O is reduced to low levels in the expansion stroke after initially increasing due to the thermal de-NOx mechanism. This indicates that N<sub>2</sub>O emissions measured from premixed engine combustion are likely from quenching near cold surfaces.</p></div>","PeriodicalId":100104,"journal":{"name":"Applications in Energy and Combustion Science","volume":"17 ","pages":"Article 100245"},"PeriodicalIF":0.0,"publicationDate":"2024-01-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.sciencedirect.com/science/article/pii/S2666352X23001346/pdfft?md5=d6446272d72ddf644eac87d8c1ee03c5&pid=1-s2.0-S2666352X23001346-main.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139392347","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Thermodynamic and kinetic modeling and experiment on plasma ignition of pulverized high-ash coal","authors":"Vladimir E. Messerle, Alexandr B. Ustimenko","doi":"10.1016/j.jaecs.2024.100248","DOIUrl":"https://doi.org/10.1016/j.jaecs.2024.100248","url":null,"abstract":"<div><p>Solid fuels are relatively inexpensive and widely available, making them an attractive option for energy producers. However, they are currently inefficient in converting heat energy into electricity, and new technological advances are needed to make them more efficient. Plasma ignition and stabilization of pulverized coal flame provides a cost-effective and sustainable approach to boiler start-up and combustion stabilization, avoiding the traditionally used fuel oil or gas. This technology consists of heating the air-coal mixture with electric arc plasma to the temperature of coal devolatilization and partial gasification of the coke residue. Thus, a highly reactive two-component fuel, consisting of combustible gas and coke residue, is obtained from the original coal. In this paper, a comprehensive thermodynamic and kinetic analysis was carried out. A thermodynamic analysis was carried out to study the optimal parameters of plasma ignition and stabilization of combustion of a pulverized fuel flame. Kinetic modeling of the process of plasma ignition and stabilization of combustion of pulverized fuel made it possible to obtain changes in temperatures, velocities and concentrations of high-temperature two-component fuel components along the length of the plasma-fuel system. In experiments on plasma ignition of thermal coal, a stable coal-dust flame was obtained, and its temperature, composition and degree of carbon gasification were determined. Comparison of experimental and calculated data showed satisfactory agreement.</p></div>","PeriodicalId":100104,"journal":{"name":"Applications in Energy and Combustion Science","volume":"17 ","pages":"Article 100248"},"PeriodicalIF":0.0,"publicationDate":"2024-01-04","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.sciencedirect.com/science/article/pii/S2666352X24000037/pdfft?md5=7b94a618d9241966a44e74bb74d37543&pid=1-s2.0-S2666352X24000037-main.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139111448","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Xiaoxiang Shi , Tianyou Lian , Yi Zhang, Zundi Liu, Wei Li, Zhongya Xi, Yuyang Li
{"title":"Enhanced ammonia combustion by partial pre-cracking strategy in a gas turbine model combustor: Flame macrostructures, lean blowout characteristics and exhaust emissions","authors":"Xiaoxiang Shi , Tianyou Lian , Yi Zhang, Zundi Liu, Wei Li, Zhongya Xi, Yuyang Li","doi":"10.1016/j.jaecs.2024.100247","DOIUrl":"10.1016/j.jaecs.2024.100247","url":null,"abstract":"<div><p>Cofiring with hydrogen presents a reasonable approach to achieve enhanced ammonia (NH<sub>3</sub>) combustion without introducing an extra carbon footprint. A promising strategy for NH<sub>3</sub>/H<sub>2</sub> cofiring in gas turbines involves on-site partial pre-cracking of NH<sub>3</sub> and burns of NH<sub>3</sub>/H<sub>2</sub>/N<sub>2</sub> mixtures, eliminating additional hydrogen transportation and storage. This work investigates the effects of the pre-cracking ratio (<em>γ</em>) on flame macrostructures, lean blowout characteristics and exhaust emissions of the partially pre-cracked NH<sub>3</sub> flames in a single-swirl gas turbine model combustor. Flow and flame macrostructures were captured using particle image velocimetry (PIV) and OH planar laser-induced fluorescence (OH-PLIF) measurements. Lean blowout limits (<em>ϕ</em><sub>LBO</sub>) were assessed under varying <em>γ</em>, and emissions at the burner outlet were measured using a Fourier transform infrared spectroscopic (FTIR) gas analyzer. Results show that as <em>γ</em> increases, the flame exhibits a shortened height, strengthened OH fluorescence, amplified core jet velocities and significantly reduced <em>ϕ</em><sub>LBO</sub>, indicating an effective enhancement of NH<sub>3</sub> combustion by partial pre-cracking strategy. Nevertheless, NO and NO<sub>2</sub> emissions exhibit a substantial increase with larger <em>γ</em>. Opposite trends of NO and NH<sub>3</sub> emissions versus equivalence ratio (<em>ϕ</em>) suggest a trade-off between NO and NH<sub>3</sub> emissions, with relatively low NO/NH<sub>3</sub> window appearing under slightly-rich (<em>ϕ</em> = 1.0–1.1) conditions. Low NO emissions are also noted under ultra-lean conditions (<em>ϕ</em> = 0.4–0.5) with the penalty of high NH<sub>3</sub> and N<sub>2</sub>O emissions, making it an unacceptable trade-off. Furthermore, the effect of N<sub>2</sub> separation from the partially pre-cracked NH<sub>3</sub> mixtures was evaluated at <em>γ</em> = 0.4. The results show deteriorating effects on NOx emissions, resulting in 13 % and 21 % increases in peak NO and NO<sub>2</sub> emissions, respectively, which implies more feasibility to burn the partially pre-cracked NH<sub>3</sub> in a direct manner rather than N<sub>2</sub> separation.</p></div>","PeriodicalId":100104,"journal":{"name":"Applications in Energy and Combustion Science","volume":"17 ","pages":"Article 100247"},"PeriodicalIF":0.0,"publicationDate":"2024-01-04","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.sciencedirect.com/science/article/pii/S2666352X24000025/pdfft?md5=c74fe0a6205c93760bef8c23c89fd92c&pid=1-s2.0-S2666352X24000025-main.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139392494","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Flow-field design of the bipolar plates in polymer electrolyte membrane fuel cell: Problem, progress, and perspective","authors":"Yong Zhang , Zhengkai Tu","doi":"10.1016/j.jaecs.2023.100244","DOIUrl":"10.1016/j.jaecs.2023.100244","url":null,"abstract":"<div><p>As a promising carbon-neutral technology, the polymer electrolyte membrane fuel cell (PEMFC) is gaining considerable attention over the past decades. Many problems in PEMFC performance and durability can be ultimately ascribed to the flow-field design, which is a complex and systematic work owing to the inherent sophisticated nature of the PEMFC with multicomponent mass transportation and multiphysics field coupling. This paper presents a critical review of the state-of-the-art flow-field designs and an in-depth analysis of the key problems involved from a perspective of efficient mass transport within the PEMFC. In particular, flow-optimization principles are discussed specifically for the enhancement in reactant mass transfer, water management, optimized opening ratio, uniformity of flow distribution, and choice of appropriate numerical approaches assisting the flow-field design. The material formability and forming accuracy and their effects are also discussed for metallic bipolar plates. The objective of this review work is to present a comprehensive overview of the problems, progresses, and perspectives of the flow-field designs for bipolar plates in PEMFC and provide a general theoretical instruction for present and future relevant R&D activities that aim at high-performance, durable, and low-cost fuel cells.</p></div>","PeriodicalId":100104,"journal":{"name":"Applications in Energy and Combustion Science","volume":"17 ","pages":"Article 100244"},"PeriodicalIF":0.0,"publicationDate":"2024-01-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.sciencedirect.com/science/article/pii/S2666352X23001334/pdfft?md5=82c2202c74b0d892f60595829f22b6e0&pid=1-s2.0-S2666352X23001334-main.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139393720","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Enhancing water hydration in air-cooled proton exchange membrane fuel cell using a staggered tapered slotted flow field","authors":"Jianfei Zhang, Wei Li, Guobin Zhang, Hongwei Bai, Zhiguo Qu","doi":"10.1016/j.jaecs.2023.100239","DOIUrl":"10.1016/j.jaecs.2023.100239","url":null,"abstract":"<div><p>Air-cooled proton exchange membrane fuel cell (AC-PEMFC) is widely considered as a promising power source for unmanned aerial vehicles (UAVs) due to its merits such as high energy density, short refueling time, and simple auxiliary system. However, the performance of AC-PEMFC is not satisfactory due to the poor membrane hydration caused by the large air supply for heat dissipation demand. This study proposes a staggered tapered slotted flow field (STSF) configuration to address this issue, which has higher contact area between the airflow and the bipolar plate by arranging tapered and slotted sections in the channels along the airflow direction, aiming to enhance the cooling effect and improve the membrane water hydration. Utilizing a three-dimensional (3D) multiphase non-isothermal model verified against experimental data, it was found that the STSF configuration reduces the internal temperature of the cell by about 14.2–28.3 K and increases the water content in the membrane by about 35.1–85.7 % compared with traditional straight channels. In addition, the STSF configuration can enhance mass transfer by inducing cross-flow, reducing concentration losses, which takes more effect for UAVs working at high altitude. Moreover, the slotted sections reduced the volume and weight of the bipolar plates, contributing to an additional power density improvement. Finally, the pressure drop within the flow channels and net power was compared. Due to the increased contact area between the cooling airflow and the bipolar plates, the STSF configuration inevitably results in a higher pressure drop within the channels, but the net power of PEMFC with STSF still increased under severe conditions by 0.080 W.</p></div>","PeriodicalId":100104,"journal":{"name":"Applications in Energy and Combustion Science","volume":"17 ","pages":"Article 100239"},"PeriodicalIF":0.0,"publicationDate":"2023-12-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.sciencedirect.com/science/article/pii/S2666352X23001280/pdfft?md5=10775af11167589661e72c0ec7b16bae&pid=1-s2.0-S2666352X23001280-main.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139193886","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Yong Wu , Mingyan Gu , Shuanglong Li , Xin Wei , Xiangyong Huang , Qifu Lin
{"title":"Study on the NOx formation of propane/ammonia co-combustion with a swirl burner","authors":"Yong Wu , Mingyan Gu , Shuanglong Li , Xin Wei , Xiangyong Huang , Qifu Lin","doi":"10.1016/j.jaecs.2023.100242","DOIUrl":"10.1016/j.jaecs.2023.100242","url":null,"abstract":"<div><p>Replacing traditional fuels with carbon free fuel ammonia is one of the important ways to achieve low carbon emissions. However, the problem of high concentration NOx formation in the process of ammonia combustion is still a topic of great concern. In this paper, the combustion experimental system was built to study the NOx generation characteristics of ammonia propane combustion for a swirl burner. The experimental results show that the addition of ammonia into propane flame greatly increases the amount of NOx, and reasonable organization of ammonia doping ratio and primary air ratio can effectively control the generation of NOx. When the ammonia doping ratio is less than 15%, the highest NOx appeared with the primary air ratio of 20%. When the ammonia ratio was greater than 15%, the increase of the primary air ratio had no obvious effect on the formation of NOx near the swirl burner. The flame temperature changes with the ammonia doping ratio, and when the ammonia doping ratio is 15%, the furnace gas temperature is the highest at each point along the furnace height.</p></div>","PeriodicalId":100104,"journal":{"name":"Applications in Energy and Combustion Science","volume":"17 ","pages":"Article 100242"},"PeriodicalIF":0.0,"publicationDate":"2023-12-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.sciencedirect.com/science/article/pii/S2666352X23001310/pdfft?md5=da0cb9124922dfd1ceeda3f07b007798&pid=1-s2.0-S2666352X23001310-main.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139188306","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Linhao Fan , Yang Wang , Qing Du , Meng Ni , Kui Jiao
{"title":"Linking the ionomer film morphology and nanoscale oxygen transport properties in fuel cells","authors":"Linhao Fan , Yang Wang , Qing Du , Meng Ni , Kui Jiao","doi":"10.1016/j.jaecs.2023.100243","DOIUrl":"10.1016/j.jaecs.2023.100243","url":null,"abstract":"<div><p>Transport processes are crucial for the performance of electrochemical energy conversion devices and attract wide attentions. This work focuses on the critical oxygen transport process in the ionomer electrolyte film on a Pt electrode, which highly limits the performance of low Pt-loading fuel cells. Reduction of oxygen transport resistance may be achieved by optimizing the ionomer film morphology. Therefore, the relationship between ionomer film morphology and oxygen transport characteristics is explored by altering ionomer side chain lengths in this work. The results show that the swollen structure with larger water agglomerates in the ionomer film with shorter ionomer side chains is detrimental to the formation of oxygen transport paths. However, the multilamellar structure with an alternating alignment of water agglomerates and PFSA ionomer agglomerates in the ionomer film with longer ionomer side chains has a larger water-PFSA interface, which provides more oxygen transport paths and thus reduces the oxygen transport resistance. This work inspires the novel design concept of the ionomer electrolyte film with low local oxygen transport resistance, i.e., enlarging the water-PFSA interface parallel to the oxygen transport direction via altering the ionomer material properties, which is valuable for the development of low Pt-loading fuel cells.</p></div>","PeriodicalId":100104,"journal":{"name":"Applications in Energy and Combustion Science","volume":"17 ","pages":"Article 100243"},"PeriodicalIF":0.0,"publicationDate":"2023-12-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.sciencedirect.com/science/article/pii/S2666352X23001322/pdfft?md5=33af514ce5341c8fe5f401670fcb9acb&pid=1-s2.0-S2666352X23001322-main.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139192218","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Tengda Song, Can Wang, Mingsheng Wen, Haifeng Liu, Mingfa Yao
{"title":"Combustion mechanism study of ammonia/n-dodecane/n-heptane/EHN blended fuel","authors":"Tengda Song, Can Wang, Mingsheng Wen, Haifeng Liu, Mingfa Yao","doi":"10.1016/j.jaecs.2023.100241","DOIUrl":"https://doi.org/10.1016/j.jaecs.2023.100241","url":null,"abstract":"<div><p>Due to the challenges of ammonia, such as high ignition energy and slow flame propagation speed, the utilization of ammonia in engines might necessitate the implementation of dual-fuel combustion modes along with the use of cetane improvers. To optimize the performance of ammonia-fueled engines, and achieve efficient and clean combustion, three-dimensional computational fluid dynamics (CFD) simulations are imperative. However, prior to conducting a three-dimensional CFD study, an accurate reaction mechanism for each component is essential. In this study, the blending mechanisms of ammonia, n-dodecane, and 2-ethylhexyl nitrate (EHN) were constructed using CHEMKIN software, including 243 species and 1293 reactions. The calculated results of ignition delay, laminar flame velocity, and the concentration of significant species agreed well with experiment results. The ignition delay, laminar flame velocity, adiabatic flame temperature, and the concentration of major products were analyzed in different blending ratios. The use of high cetane fuel shortens ignition delay and increases laminar flame speed. As the equivalence ratio of ammonia increases, the concentration of NO decreases while the concentration of H<sub>2</sub> increases. The combustion process is also analyzed based on optical diagnostic results, and the impact of the ammonia/n-dodecane mixtures blended with EHN on the combustion process is investigated. The addition of EHN proved to shorten the ignition delay of the mixture. Furthermore, the introduction of EHN exhibits marginal influence on NOx generation, with the predominant augmentation of NOx emissions stemming from fuel-derived NOx resulting from the fuel's inherent nitrogen content. Due to the small amount of EHN added, the overall impact is relatively small.</p></div>","PeriodicalId":100104,"journal":{"name":"Applications in Energy and Combustion Science","volume":"17 ","pages":"Article 100241"},"PeriodicalIF":0.0,"publicationDate":"2023-12-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.sciencedirect.com/science/article/pii/S2666352X23001309/pdfft?md5=5e4c094db5c403ecbb96b6cabc22b48a&pid=1-s2.0-S2666352X23001309-main.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139108497","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Cobalt–organic framework as a Bi–functional electrocatalyst for renewable hydrogen production by electrochemical water splitting","authors":"Eshagh Irandoost , Neda Sadat Barekati , Hossein Farsi , Alireza Farrokhi , Garren Horvath , Zhihai Li","doi":"10.1016/j.jaecs.2023.100240","DOIUrl":"https://doi.org/10.1016/j.jaecs.2023.100240","url":null,"abstract":"<div><p>Sustainable hydrogen production by electrocatalytic water splitting is an attractive approach to establish a carbon–free future. On the other hand, the operationalization of this technology on a large scale requires the design and synthesis of efficient electrocatalysts to promote hydrogen evolution reaction (HER) and oxygen evolution reaction (OER). Metal–organic frameworks (MOFs) have provided new opportunities in the field of electrocatalytic water splitting due to their unique properties. Herein, we report an affordable, simple, and environmentally friendly strategy for the synthesis of Co<sub>3</sub>(BTC)<sub>2</sub> MOF electrocatalyst in distilled water at room temperature. Surprisingly, Co<sub>3</sub>(BTC)<sub>2</sub> demonstrated superior electrocatalytic activity toward HER and OER in alkaline media. The Co<sub>3</sub>(BTC)<sub>2</sub> requires overpotentials of 450 and 370mV for HER and OER to achieve a current density of 10mA cm<sup>−2</sup>, respectively.</p></div>","PeriodicalId":100104,"journal":{"name":"Applications in Energy and Combustion Science","volume":"17 ","pages":"Article 100240"},"PeriodicalIF":0.0,"publicationDate":"2023-12-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.sciencedirect.com/science/article/pii/S2666352X23001292/pdfft?md5=a887a03b173639043e0dad73d04cb5ec&pid=1-s2.0-S2666352X23001292-main.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139109272","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Syed Saqline , Haiming Wang , Qianwenhao Fan , Felix Donat , Christoph Müller , Wen Liu
{"title":"Investigation of barium iron oxides for CO2 capture and chemical looping oxygen uncoupling","authors":"Syed Saqline , Haiming Wang , Qianwenhao Fan , Felix Donat , Christoph Müller , Wen Liu","doi":"10.1016/j.jaecs.2023.100238","DOIUrl":"10.1016/j.jaecs.2023.100238","url":null,"abstract":"<div><p>The performance of two underexploited ternary oxides – Ba<sub>3</sub>Fe<sub>2</sub>O<sub>6</sub> and Ba<sub>5</sub>Fe<sub>2</sub>O<sub>8</sub> are investigated for carbon dioxide capture and chemical looping oxygen uncoupling. The ternary compound Ba<sub>3</sub>Fe<sub>2</sub>O<sub>6</sub> was found to have a structure characterised by space group <em>Pa</em><span><math><mover><mn>3</mn><mo>¯</mo></mover></math></span>. Experimental results have shown that both Ba<sub>3</sub>Fe<sub>2</sub>O<sub>6</sub> and Ba<sub>5</sub>Fe<sub>2</sub>O<sub>8</sub> are capable of cyclically capturing CO<sub>2</sub> at temperatures above 800 °C. Ba<sub>5</sub>Fe<sub>2</sub>O<sub>8</sub> demonstrated superior CO<sub>2</sub> capture performance compared to Ba<sub>3</sub>Fe<sub>2</sub>O<sub>6</sub>, with consistent gravimetric CO<sub>2</sub> uptake capacities of 4.35 wt% and 13.39 wt% at 900 °C and 1000 °C, respectively, over 20 cycles. In comparison, Ba<sub>3</sub>Fe<sub>2</sub>O<sub>6</sub> demonstrated high initial CO<sub>2</sub> uptake capacities which deteriorated cyclically, with 20 cycle average capacities of 7.73 wt% and 11.99 wt% at 900 °C and 1000 °C, respectively. Ba<sub>3</sub>Fe<sub>2</sub>O<sub>6</sub> also exhibits excellent recyclability and satisfactory chemical looping oxygen uncoupling (CLOU) activity over temperature swing cycles between 550 °C and 950 °C. In contrast, the strong affinity with CO<sub>2</sub> makes Ba<sub>5</sub>Fe<sub>2</sub>O<sub>8</sub> unsuitable for application in chemical looping oxygen uncoupling or chemical looping air separation, especially in the presence of substantial partial pressures of CO<sub>2</sub>.</p></div>","PeriodicalId":100104,"journal":{"name":"Applications in Energy and Combustion Science","volume":"17 ","pages":"Article 100238"},"PeriodicalIF":0.0,"publicationDate":"2023-12-26","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.sciencedirect.com/science/article/pii/S2666352X23001279/pdfft?md5=0bc3d8f866208447e2f4a8e0531e589f&pid=1-s2.0-S2666352X23001279-main.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139188961","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}