CERAMICS INTERNATIONAL
·
2024
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IF 5.1
Xin Wang,Yunfei Gao,Zhiyang Cai,Shan Hu,Junxian Zhang,Fuchen Wang,Yifei Wang
Chemical looping air separation (CLAS) represents a promising approach to use thermal energy for high-purity oxygen production. CeO 2 represents a class of material that uncouples oxygen using thermal energy, but the required temperature is usually very high (>1400 °C). This limits the potential use for CeO 2 -based materials in CLAS. This study reports a Pr doped CeO 2 oxygen sorbents for chemical looping air separation at ultra-low temperatures. The as-formed Ce 1-x Pr x O 2 solid solution can uncouple oxygen effectively, achieving a redox oxygen capacity of 0.88 wt% at isothermal condition as low as 500 °C. The redox oxygen capacity can be further enhanced to 1.63 wt% in temperature-swing cycles between 400 °C and 900 °C. Moreover, oxygen partial pressure-swing cycles show that the Ce 1-x Pr x O 2 solid solution maintains 95% of its redox oxygen capacity at oxygen partial pressure as low as 0.02 atm, indicating its potential applications in oxygen separation from diluted air. DFT calculations and other physio-chemical characterizations indicate that Pr doping can effectively reduce the oxygen vacancy formation energy, and gaseous oxygen is uncoupled when Pr 4+ and Ce 4+ are reduced in the Ce 1-x Pr x O 2 solid solution. Overall, this study highlights the novel performance of CeO 2 with Pr doping and could offer insights into CeO 2 modification strategies for thermal chemical applications.
研究领域:
材料科学
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化学工程
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DOI
高影响因子
Inorganics
·
2024
·Vol. 12
·期 9
·250
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IF 3.1
Ye Li,Huiqing Yue,Quanli Zhang,Dumin Yan,Ziyi Li,Zhiwei Liu,Yingshu Liu,Yongyan Wang,Shifeng Wang,Xiong Yang
In oxygen production on plateaus, pressure swing adsorption (PSA) oxygen production is currently the most commonly used oxygen production method. In plateau regions, low pressure leads to a decrease in adsorbent nitrogen–oxygen separation performance, which affects the performance of PSA oxygen production, so it is particularly important to enhance adsorbent nitrogen–oxygen separation performance. In this paper, Li-LSX (lithium low-silicon aluminum X zeolite molecular sieve) adsorbents were modified using the liquid phase ion exchange method, and five kinds of modified adsorbents were obtained, namely AgLi-LSX, CaLi-LSX, ZnLi-LSX, CuLi-LSX, and FeLi-LSX, respectively. The influences of different metal ions and modification time lengths on the adsorbent nitrogen adsorption and nitrogen–oxygen separation coefficients were analyzed. Through theoretical calculations, the nitrogen and oxygen adsorption and separation performances of the modified adsorbents at different altitudes and low adsorption pressures were investigated. It is shown that the nitrogen adsorption capacity of the AgLi-LSX-1 adsorbent obtained from the modification experiment reaches 27.92 mL/g, which is 3.24 mL/g higher than that of Li-LSX; the nitrogen–oxygen separation coefficients of S1 and S2 are 19.24 and 7.54 higher, respectively; and the nitrogen–oxygen separation coefficients of S4 are 20.85 and 7.54 higher than those of Li-LSX, respectively. With the increase in altitude from 50 m to 5000 m, the nitrogen–oxygen separation coefficient of the AgLi-LSX-1 adsorbent increased rapidly from 20.85 to 57, and its nitrogen–oxygen separation coefficient S4 exceeded that of the Li-LSX adsorbent to reach 47.61 at an altitude of 4000 m. Therefore, the modified adsorbent AgLi-LSX-1 in this paper can enhance the performance of the PSA oxygen process for oxygen production in plateau applications.
研究领域:
材料科学
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环境科学
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DOI
高影响因子
CHEMICAL ENGINEERING JOURNAL
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2014
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IF 4.058
Qiuwan Shen,Ying Zheng,Cong Luo,Chuguang Zheng
Perovskite-type oxide has been considered to be an effective oxygen carrier for producing oxygen-enriched gas stream for oxy-fuel combustion application. However, the main problem with those researched perovskite-type oxides as oxygen carriers is their relatively low oxygen production amount. This has limited oxygen concentration and the productivity of the separation process. This paper reports on characteristics and oxygen production performance of improved perovskite materials of Ba–Sr–Co–Fe oxides synthesized by a new microwave-assisted EDTA method (MWA-EDTA). The effect of microwave operating times on the oxygen production properties of perovskite-type Ba 1− x Sr x Co 0.8 Fe 0.2 O 3−δ ( x = 0, 0.5, 1) as well as the cyclic performance of improved BaCo 0.8 Fe 0.2 O 3−δ (BCF) powders are investigated in details. All obtained samples are characterized using X-ray diffraction (XRD), specific surface area measurements (BET) and environmental scanning electron microscopy (ESEM). The results indicate that the samples with smaller crystallite size and higher porosity obtained by the MWA-EDTA showed better oxygen production properties than those prepared by conventional EDTA method. And the optimal microwave irradiation time for BCF is 30 min operating times. Furthermore, cyclic tests show that BCF synthesized by the optimal conditions has excellent reactivity and regeneration capacity after 21 cycles.
研究领域:
材料科学
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能源化学
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无机功能材料
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燃烧工程
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气体分离技术
✓ 已验证
DOI
高影响因子
CHEMICAL ENGINEERING JOURNAL
·
2025
·
IF 13.2
Yeku Wang,Shengxin Li,Deqiu Zou,Nan Sheng,Chunyu Zhu
Developing high-performance materials for integrated thermal energy storage and oxygen production is critical for advancing sustainable energy systems. Aluminum as heat storage phase change materials has a high latent heat storage density, but suffering from the leakage problems. The SrFeO 3− δ (SFO) oxygen carrier exhibits exceptional redox activity for air separation with a high reduction enthalpy of 96 kJ/mol. In this study, we report a multifunctional composite macrocapsules composed of SFO shell and metallic aluminum core, engineered to synergistically combine thermochemical, latent, and sensible heat storage with air separation capabilities. The composite macrocapsule has a high heat storage capacity of 435.9 J/g at a temperature duration of 873 K to 1073 K and an oxygen storage capacity of 1.69 wt%. After conducting 50th thermal cycles in air for the composite macrocapsules, the samples remain unbroken and the oxygen absorption/release and heat storage capacities remain stable. The synergy between the thermochemical properties of SFO and the phase change heat storage of aluminum enables dual functionality, i.e., efficient high-temperature heat storage and on-demand air separation for chemical looping applications. This work provides a scalable paradigm for multifunctional energy materials, bridging the gap between thermal management and carbon neutral technologies.
研究领域:
材料科学
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储能技术
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化学工程
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热管理
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可持续能源
✓ 已验证
产品关联
DOI
高影响因子
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