Article
Energy & Fuels
Richard A. Newby, Dale L. Keairns, Robert W. Stevens
Summary: The objective of this study was to estimate the cost of commercial production of oxygen carriers (OCs) for large-scale application in the chemical looping combustion (CLC) power generation industry. Two production facility scenarios were considered, and two OC production techniques were addressed. The estimated OC product costs can be used to guide development and determine the maximum OC makeup rate for achieving a designated cost-of-electricity (COE) reduction goal.
Article
Engineering, Environmental
Lei Liu, Zhenshan Li, Yang Wang, Zuoan Li, Yngve Larring, Ningsheng Cai
Summary: A spray drying granulation protocol was developed to produce an industrial-scale perovskite oxygen carrier. Micro-fluidized bed thermogravimetric experiments were performed to measure the reaction kinetics, and the obtained data was fitted by a semi-empirical kinetic model. The upscaled granulates showed similar physical and chemical properties to the laboratory-scale particles, with high reaction rates, low attrition rates, and low energy consumption.
CHEMICAL ENGINEERING JOURNAL
(2022)
Article
Thermodynamics
Feng Liu, Jing Liu, Yu Li, Ruixue Fang, Yingju Yang
Summary: The study found that spinel NiFe2O4 can be directly reduced into Ni-Fe alloy in CO atmosphere, with a reaction rate two times faster than Fe2O3. Factors such as reaction temperature, CO concentration, and heating rate can enhance the reactivity of NiFe2O4. The reactivity of lattice oxygen in NiFe2O4 is primarily influenced by the coordination environment of oxygen formed by different Ni/Fe atoms.
Article
Engineering, Environmental
Inaki Adanez-Rubio, Francisco Garcia-Labiano, Alberto Abad, Luis F. de Diego, Juan Adanez
Summary: The use of bio-oil produced by biomass fast pyrolysis in Chemical Looping Reforming can efficiently generate hydrogen gas while reducing carbon deposition.
CHEMICAL ENGINEERING JOURNAL
(2022)
Article
Energy & Fuels
Yuchuan Feng, Nana Wang, Xin Guo
Summary: DFT calculations were used to explore the reaction mechanism of methane conversion over Ca2Fe2O5 oxygen carrier in chemical looping hydrogen production. The study found that while H-2 generation is difficult on the surface of Ca2Fe2O5, CO formation is prone to occur and the oxygen diffusion needs to overcome a high energy barrier. The activation of CH4 was identified as the dominant rate-determining step, suggesting the need for promoters to enhance the CH4 reactivity of Ca2Fe2O5.
Review
Chemistry, Physical
Wenxi Chang, Yue Hu, Weibin Xu, Chuande Huang, Haonan Chen, Jiahui He, Yujia Han, Yanyan Zhu, Xiaoxun Ma, Xiaodong Wang
Summary: Chemical looping water-splitting (CLWS) technology is an energy-efficient and environmentally friendly method for hydrogen production. The key lies in selecting suitable oxygen carriers (OCs). This review discusses recent advances in designing OCs and emphasizes the crucial parameters that determine their redox performance and future challenges.
Article
Energy & Fuels
Shuoxin Zhang, Xin Guo
Summary: This study applied a novel iron-based oxygen carrier based on natural mineral attapulgite (ATP) to chemical looping hydrogen production (CLH) technology, and investigated the effects of support on the performance of the oxygen carrier as well as its mechanism in the CLH process. The results showed that Fe2O3 supported by ATP had superior activity and stability compared to those supported by expanded perlite, kaolin or Al2O3. In particular, Fe6ATP4 exhibited a high hydrogen yield at 850 degrees C which was twice as high as that of Fe2O3/Al2O3. Experimental and theoretical methods validated the excellent reaction performance of Fe2O3/ATP. DFT calculations revealed stronger delocalization of electrons in the Fe2O3/ATP system compared to Fe2O3/Al2O3. XPS analysis showed more defect oxides or hydroxyl groups on the surface of ATP-supported Fe2O3, which further facilitated the reduction reaction.
Article
Engineering, Chemical
Chenlong Liu, Jing Luo, Hao Dong, Zhihua Zhao, Chenghua Xu, Siddig Abuelgasim, Atif Abdalazeez, Wenju Wang, Dengke Chen, Qianlin Tang
Summary: In this study, iron-based oxygen carriers modified by different ratios of Ca were prepared via the sol-gel method. The hydrogen production performance of these carriers in a fixed-bed system was investigated by reacting them with biomass char. The results showed that the CaFe2O4 sample exhibited excellent hydrogen yield at specific temperature and ratio, and maintained stable performance after cycling experiments.
SEPARATION AND PURIFICATION TECHNOLOGY
(2022)
Article
Chemistry, Applied
Dingshan Cao, Cong Luo, Wenting Xing, Guoqiu Cai, Tong Luo, Fan Wu, Xiaoshan Li, Liqi Zhang
Summary: Coal-direct chemical looping hydrogen generation (CDCLHG) is a novel process that directly produces H-2 from coal and captures CO2. In this study, perovskite oxygen carriers were synthesized and BaMnO3 was found to be the optimal oxygen carrier for CDCLHG, achieving high H-2 gas production with a high H-2 gas production rate. The BaMnO3-delta obtained during the reaction process showed the conversion of lattice oxygen to carbonate oxygen and can recover its initial structure.
FUEL PROCESSING TECHNOLOGY
(2022)
Article
Chemistry, Multidisciplinary
Xiao Zhang, Yao Xu, Yang Liu, Liang Niu, Yanan Diao, Zirui Gao, Bingbing Chen, Jinglin Xie, Mingshu Bi, Meng Wang, Dequan Xiao, Ding Ma, Chuan Shi
Summary: In this study, researchers propose a novel MoCxOy oxygen carrier for syngas production through the chemical looping CH4-CO2 reforming reaction. The combination of molybdenum carbide and nickel particles enables high-selectivity CH4 activation at low temperatures. This is the first study to utilize molybdenum carbide as an oxygen storage material, paving the way for the use of transition metal carbides in chemical looping processes.
Article
Energy & Fuels
Feng Liu, Fan Wu, Jing Liu, Yu Li, Yingju Yang
Summary: The reduction of CoFe2O4 is a one-step reaction process, and the presence of Co improves its reactivity. Two types of reaction kinetics are involved in the isothermal reduction of CoFe2O4.
Article
Chemistry, Physical
Yu Qiu, Li Ma, Qingfeng Kong, Min Li, Dongxu Cui, Shuai Zhang, Dewang Zeng, Rui Xiao
Summary: Operating chemical looping process at mid-temperatures presents exciting potential for stable hydrogen production. Incorporating earth-abundant metals into the iron-based spinel for hydrogen production shows high performance comparable to noble metal containing materials, enabling their potential for industrial applications.
GREEN ENERGY & ENVIRONMENT
(2021)
Article
Chemistry, Physical
Chenlong Liu, Dengke Chen, Qianlin Tang, Siddig Abuelgasim, Chenghua Xu, Wenju Wang, Jing Luo, Zhihua Zhao, Atif Abdalazeez, Ruyue Zhang
Summary: The effect of Mn doping on Fe2O3 for hydrogen-rich syngas production from biomass char has been studied. Mn doping enhanced the redox activity and oxygen vacancies, leading to increased hydrogen gas generation. Optimum conditions for maximum hydrogen gas yield were determined.
INTERNATIONAL JOURNAL OF HYDROGEN ENERGY
(2023)
Article
Thermodynamics
Min Li, Laizhi Sun, Lei Chen, Hongqing Feng, Baofeng Zhao, Shuangxia Yang, Xinping Xie, Xiaodong Zhang
Summary: The combination of Fe2O3 and CaO as oxygen carriers showed the best activity for chemical looping gasification of biomass. The maximum syngas yield was achieved at a sawdust:Fe2O3:CaO mass ratio of 2:2:1 and a reaction temperature of 850 degrees C. Fe2O3 provided oxygen for gasification, while CaO absorbed CO2 and catalyzed reactions, showing good cycling characteristics.
JOURNAL OF THERMAL ANALYSIS AND CALORIMETRY
(2022)
Article
Engineering, Environmental
Yunlei Zhao, Bo Jin, Lin Zhang, Wenhao Ji, Zhiwu Liang
Summary: In this study, a series of microstructured iron-based spinel oxygen carriers were synthesized by thermal transformation of Prussian blue analogues using other active metals. The structure, cyclic stability, and CO yield of the oxygen carriers were extensively characterized. It was found that all the spinel oxygen carriers showed special morphologies and good reactivity. NiFe-Zr material exhibited the highest CO2 conversion rate without deactivation, attributed to the catalytic role of Ni and the formation of Fe3O4 during redox cycles. This work provides a new approach for the design of efficient spinel oxygen carriers for chemical looping CO2 conversion.
CHEMICAL ENGINEERING JOURNAL
(2023)
