STRUCTURE AND PROPERTIES OF Ni/Mg-Al CATALYST MODIFIED BY DIFFERENT METAL ELEMENTS

Abstract

Abstract: Using MgO, Al2O3 and ZrO powder as carriers, nickel as active component and cobalt and lanthanum as auxiliary agents, ultra-high temperature ammonia decomposition catalysts were prepared. The structure of which was characterized by XRD, BET, TPR and TEM.To investigate the influence of different metal elements on the structure and performance of catalyst, catalyst evaluation device was used. XRD results show that NiAl2O4 spinel phase exists in all the catalysts; metal elements can promote the crystalline form of NiAl2O4 spinel; compared with Co and Zr, La contributes more to the crystalline form. TPR results show that more crystalline phase of NiAl2O4could be formedafter adding of La, and a stronger interaction with carrier is formed after adding Co. BET and TEM experiment show that La is helpful to improve the dispersion and concentration of Ni species on the catalyst surface, and to form smaller surface nickel particles, so as to improve the active site distribution of nickel. Compared with Ni/Mg-Al and CoNi/ZrMg-Al catalysts, LaNi/ZrMg-Al catalyst shows better high temperature wear resistance, sintering resistance and thermal stability under experimental condition of reaction temperature 1200 ℃, volume space velocity 1228 h-1.

Key words: metallic element, extraordinarily high temperature, ammonia decomposition, Ni/Mg-Al catalyst

CLC Number:

References

[1] GANLEY J C, THMAL F S, SEEBAUER EG.?A priori catalytic actibvity correlations: the difficult case of hydrogen production from ammonia[J]. Catalysis Letters, 2004, 96：117-122.
[2] NISHIKAWA S. Structure of some crystals of the spinel group[J]. Journal of the Physical Society, 1915, 8: 199-209.
[3] CARTER R E. Mechanism of solid-state reaction between magnesium oxide and aluminum oxide and between magnesium oxide and f Ferric oxide[J]. Journal of the American Ceramic Society. 1961, 44: 116-120.
[4] HIROKI M, CHIKARA S. Ammonia decomposition over Ni /La2O3 catalyst for on-site genetation of hydrogen[J]. Applied Catalysis A: General, 2012, 443-444: 119-124．
[5] 郑维庆，徐恒泳，李文钊．乙醇促进合成Ni-Ce /Al2O3催化剂及其氨分解活性研究[J]．分子催化, 2007，21(增刊) : 405-406．
[6] 苏玉蕾，王少波，宋刚祥等．氨分解制氢技术[J]．舰船防化, 2009, (6): 6-9．
[7] ZHENG, W Q,??ZHANG J,??GE Q J,??et al．Effects of CeO2 addition on Ni /Al2O3 catalysts for the reaction of ammonia decomposition to hydrogen[J]．Applied Catalysis B: Environmental, 2008, 80(1) : 98-105．
[8] LI Y K, ZHANG Q F, CHAI R J, et al. Metal-foam-structured Ni-Al2O3 catalysts: Wet chemical etching preparation and syngas methanation performance[J]. Applied Catalysis A: General, 2016, 510(25): 216-226.
[9] ZHANG J, XU H Y, LI W Z. Kinetic study of NH3 decomposition over Ni nanoparticles: the Role of La promoter, structure sensitivity and compensation effect[J]. Applied Catalysis A: General, 2005, 26: 257-267.
[10] ZHANG J, XU H Y, JIN X L, et al. Characterizations and activities of the nano-sized Ni/Al2O3 and Ni/La/Al2O3 catalysis for NH3 decomposition[J]. Applied Catalysis A: General, 2005, 290: 87-96.
[11] 郑维庆，陈燕馨，徐恒泳等. 氨分解反应纳米镍基催化剂的研究[J]. 天然气化工：CI化学与化工, 2007, 32: 31-36.
[12] 陈金妹，谈萍，王建永.气体吸附法表征多孔材料的比表面积及孔结构[J]. 粉末冶金工业. 2011, 21（2）：45-49.
[13] 中华人民共和国国家标准. GB/T 21652-2008, 压汞法和气体吸附法测定固体材料孔径分布和孔隙度-3: 气体吸附法分析微孔[S], 北京：中国标准出版社，2009.
[14] 张超武，张利娜，张楠等. 镁铝尖晶石催化剂载体的制备及表征[J]. 陕西科技大学学报(自然科学版)?, 2016: (6): 42-58.
[15] 张建. 氨分解制氢与把膜分离氢的研究[D]. 大连：中国科学院大连化学物理研究所, 2006.
[16] 吴建峰，赵娜，徐晓虹等. La3+掺杂对纳米ZnO晶粒度及光催化性能的影响[J]. 武汉理工大学学报, 2008, 7(30): 5-9.
[17] KOO K Y, ROH H S, SEO Y T, et al. Coke study on MgO-promoted Ni/Al2O3 catalyst in combined H2O and CO2 reforming of methane for gas to liquid (GTL) process[J]. Applied Catalysis A: General, 2008, 340(2): 183-190.
[18] KOO K Y, ROH H S, SEO Y T, et al. A highly effective and stable nano-sized Ni/MgO-Al2O3?catalyst for gas to liquids (GTL) process[J]. International Journal of Hydrogen Energy, 2018，33(8): 2036-2043.
[19] 汪学广, 尚兴付, 丁伟中等，无比表面活性剂制备介孔NiAl2O4材料的方法[P]. 中国专利：CN102649590A, 2012-05-04.
[20] Arena F, Frusteri F, Parmaliana A, et al. Effect of calcination on the structure of Ni/MgO catalyst: an X-ray diffraction study [J]. J Chem Soc, Faraday Trans, 1996, 92(3): 469-471.
[21] Kang, Ki-Moon;?Kim, Hyo-Won;?Shim, Il-Wun;?Kwak, Ho-Young. Catalytic test of supported Ni catalysts with core/shell structure for dry reforming of methane[J]. Fuel Processing Technology, 2011, 92 (6): 28-32.
[22] 杨军. Ni /MgO/Al2O3催化剂上以1-甲基萘为模型化合物高温焦炉煤气焦油的催化转化[J]. 高等学校化学学报, 2010, 31(9): 1841-1847.
[23] TAKENAKA S, TOMIKUBO Y, KATO E, et al. Sequential production of H2 and CO over supported Ni catalysts[J]. Fue, 2004, 83(1): 47-57.
[24] SAITO R, FUJITA M, DRESSELHAUS G. Electronic structure of chiralgraphene tubules[J], Appl Phys Lett, 1992, 60: 2204-2206.
[25] RYNKOWSKI J M, PARYJCZAK T, LENIK M.On the nature of oxidic nickel phases in Ni O/γ-Al2O3 catalyst[J]. Applied Catalysis A:General, 1993, 106 (1): 73-82.
[26] 张玉红, 熊国兴, 盛世善, 等. NiO /γ -A l2O3中NiO 与γ -Al2O3间的相互作用[J]. 物理化学学报, 1999, 15(8): 735-741.
[27] Cédric,?Gennequin, Stéphane, et al. Co–Mg–Al Hydrotalcite Precursors for Catalytic Total Oxidation of Volatile Organic Compounds[J]. Topics in Catalysis, 2009, 52(5): 482-491.
[28] Sánchez-Sánchez M C，Navarro R M，Fierro J L G. Ethanol steam reforming over Ni/MxOy-Al2O3 (M=Ce，La，Zr and Mg) catalysts：Influence of support on the hydrogen production[J]. Int. J. Hydrogen Energy, 2007, 32(10): 1462-1471.
[29] Dias J A C，Assaf J M. Autothermal reforming of methane over Ni/γ-Al2O3 promoted with Pd：The effect of the Pd source in activity，temperature profile of reactor and in ignition[J]. Appl. Catal. A：Gen., 2008, 334(1): 243-250.
[30] 张钦辉, 秦永宁. 载体和助剂对NiO催化剂氨分解反应的影响[J]. 石油学报(石油加工)，2002, 18(4): 43-46.