物理化学学报 >> 2016, Vol. 32 >> Issue (6): 1527-1533.doi: 10.3866/PKU.WHXB201603161

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铈镧比对CexNi0.5La0.5-xO系催化剂甘油氧化蒸汽重整制氢性能的影响

党成雄,杨浩波,余皓*(),王红娟,彭峰   

  • 收稿日期:2016-01-04 发布日期:2016-06-03
  • 通讯作者: 余皓 E-mail:yuhao@scut.edu.cn
  • 基金资助:
    国家自然科学基金(20176094);教育部新世纪优秀人才支持计划项目(NCET-12-0190);广州市珠江科技新星项目(2011J2200062)

CexNi0.5La0.5-xO Catalysts for Hydrogen Production by Oxidative Steam Reforming of Glycerol: Influence of the Ce-to-La Ratio

Cheng-Xiong DANG,Hao-Bo YANG,Hao YU*(),Hong-Juan WANG,Feng PENG   

  • Received:2016-01-04 Published:2016-06-03
  • Contact: Hao YU E-mail:yuhao@scut.edu.cn
  • Supported by:
    The project was supported by the National Natural Science Foundation of China(20176094);Program for New Century Excellent Talents in University of Ministry of Education of China(NCET-12-0190);Pearl River Nova Program of Guangzhou City, China(2011J2200062)

摘要:

利用共沉淀法制备了CeO2和La2O3复合载体的CexNi0.5La0.5-xOO(CeNiLaO)系催化剂,在固定床反应器中考察其甘油氧化蒸汽重整制氢(OSRG)性能,并采用X射线衍射(XRD)、程序升温还原(H2-TPR)、激光拉曼光谱(Raman)、扫描电子显微镜(SEM)、透射电子显微镜(TEM)和X射线光电子能谱(XPS)等手段对催化剂进行表征分析。结果表明:La2O3能够有效地分散Ni颗粒,减弱Ni颗粒在反应过程中的烧结,CeO2提供的晶格氧能够消除催化剂表面的积碳,同时La会部分进入Ce的晶格取代部分Ce4+造成晶格畸变,提高表面的氧空穴数。La2O3和CeO2的共同作用有利于减弱Ni因为烧结和积碳引起的失活。在不同Ce/La摩尔比的催化剂中,Ce0.4Ni0.5La0.1O表现出最好的催化活性,并且该催化剂在长达210 h的稳定性测试中,甘油的转化率都在95%以上,气相产物中的氢气浓度达50%。

关键词: 氧化铈, 氧化镧, 镍, 稳定性, 甘油, 制氢, 蒸汽重整

Abstract:

CexNi0.5La0.5-xO (CeNiLaO) catalysts were synthesized using a Ce-La composite oxide as the carrier via co-precipitation. They were applied in the oxidative steamreforming of glycerol (OSRG) in a fixed-bed reactor. The catalysts were characterized by X-ray diffraction (XRD), H2-temperature-programmed reduction (H2-TPR), Raman spectroscopy, scanning electron microscopy (SEM), transmission electron microscopy (TEM), and Xray photoelectron spectroscopy (XPS). The results showed that La2O3 improved the dispersion of metallic Ni and suppressed the sintering of metallic Ni particles; the lattice oxygen of CeO2 inhibited and eliminated carbon deposition on the surface of the catalysts; and the substitution of some La3+ for Ce4+ ions induced a distortion of the lattice. The synergy of La2O3 and CeO2 lessened the deactivation caused by the sintering and coke deposition and improved the catalytic performance. Among the catalysts with different molar ratios of Ce to La, Ce0.4Ni0.5La0.1O had the best catalytic activity. The conversion of glycerol remained above 95% after a 210 h stability test, while a gaseous reformate of about 50% hydrogen could be steadily produced.

Key words: CeO2, La2O3, Ni, Stability, Glycerol, Hydrogen production, Steam reforming

MSC2000: 

  • O643