CIESC Journal ›› 2023, Vol. 74 ›› Issue (10): 4286-4301.DOI: 10.11949/0438-1157.20230687

• Energy and environmental engineering • Previous Articles     Next Articles

Effect of Ba content on chemical looping dry reforming of methane performance of (La0.5Sr0.5)1-x Ba x Fe0.6Co0.4O3

Liuqing YANG(), Zirui ZHAO, Junshe ZHANG(), Jinjia WEI()   

  1. School of Chemical Engineering and Technology, Xi’an Jiaotong University, Xi’an 710049, Shaanxi, China
  • Received:2023-07-05 Revised:2023-09-07 Online:2023-12-22 Published:2023-10-25
  • Contact: Junshe ZHANG, Jinjia WEI

钡含量对(La0.5Sr0.51-x Ba x Fe0.6Co0.4O3化学链甲烷干重整性能的影响

杨柳青(), 赵子瑞, 张军社(), 魏进家()   

  1. 西安交通大学化学工程与技术学院,陕西 西安 710049
  • 通讯作者: 张军社,魏进家
  • 作者简介:杨柳青(1991—),男,博士研究生,4120116024@stu.xjtu.edu.cn
  • 基金资助:
    国家重点研发计划项目(2021YFF0500400);国家自然科学基金项目(21978230);陕西省重点研究计划项目(2022GXLH-01-08)

Abstract:

Chemical looping dry reforming of methane (CL-DRM) has the potential as an efficient technology to achieve carbon neutrality in terms of converting CH4 and CO2 to various value-added products with the minimal separation requirements. Currently, a major challenge facing this technology is the design and development of oxygen carriers with good reactivity and stability. Herein, the Ba-substituted (La0.5Sr0.5)1-x Ba x Fe0.6Co0.4O3 perovskite oxides with the anchored nanoparticles as the novel oxygen carriers were synthesized and investigated for the redox performance in the CL-DRM process based on various characterization technologies. It is found that La0.35Sr0.35Ba0.3Fe0.6Co0.4O3 oxygen carrier (x=0.3) increases the amount of oxygen consumed (5.29 mmol·g-1) and shows a higher oxygen diffusion rate to achieve the CH4 conversion of 84.3% and syngas yield of 15.23 mmol·g-1 in the CH4 reduction step. Meanwhile, the syngas selectivity of 95.8%, the CO selectivity of 70.0% and carbon deposition of 1.36 mmol·g-1 can be obtained. Analysis of the gas generation rate during methane reduction shows that Ba substitution can optimize the lattice structure of the oxygen carrier, leading to high ion mobility, promoting rapid diffusion of oxygen in the bulk phase, and thus improving CH4 conversion. Furthermore, the excellent oxygen carrier also exhibits the high structure stability and the stable regeneration ability by CO2 during the successive redox cycles.

Key words: chemical looping reforming, methane, carbon dioxide, syngas, perovskite oxides, oxygen carrier

摘要:

化学链甲烷干重整可将CH4和CO2转化为各种增值产品,是一种具有低分离要求的高效反应技术,并可助力碳中和。目前,该技术面临的一个主要挑战是设计和开发具有良好反应性和稳定性的载氧体。合成了Ba取代的具有锚定纳米颗粒的(La0.5Sr0.5)1-x Ba x Fe0.6Co0.4O3钙钛矿氧化物,将其用作化学链甲烷干重整的载氧体,通过多种表征手段和性能评价,研究了该类材料的物化性质和氧化还原性能。结果表明,在所有样品中,La0.35Sr0.35Ba0.3Fe0.6Co0.4O3在甲烷部分氧化过程中可实现84.3%的甲烷转化率、15.23 mmol·g-1的合成气产量以及最高的氧消耗量(5.29 mmol·g-1),显示出优异的氧扩散速率,同时具有95.8%的合成气选择性、70.0%的CO选择性和1.36 mmol·g-1的积炭。对甲烷还原过程中气体生成速率的分析表明,Ba取代可以优化载氧体的晶格结构,导致高的离子迁移率,促进氧在体相中的快速扩散,进而提升CH4转化。此外,氧化还原循环测试表明该载氧体具有较优异的结构稳定性和较好的再生能力。

关键词: 化学链重整, 甲烷, 二氧化碳, 合成气, 钙钛矿, 载氧体

CLC Number: