MgO/NiAl2O4 as a new formulation of reforming catalysts: Tuning the surface properties for the enhanced partial oxidation of methane
MgO/NiAl2O4 as a new formulation of reforming catalysts: Tuning the surface properties for the enhanced partial oxidation of methane
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DOI：
10.1016/j.apcatb.2016.06.045
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发表时间：
2016-12-15
影响因子：
22.1
通讯作者：
Lopez-Fonseca, Ruben
中科院分区：
文献类型：
--
作者：
Boukha, Zotihair;Jimenez-Gonzalez, Cristina;Lopez-Fonseca, Ruben
合成了氧化镁改性的镍铝尖晶石催化剂，并用BET、TEM、XRD、H-2-TPR、XPS、CO2-TPD和TGA-MS等技术对催化剂进行了表征。添加该促进剂诱导所得尖晶石衍生催化剂的织构、结构和化学性质的显著变化。因此，它增强了对烧结的沉积的Ni颗粒的电阻，而在增加MgO负载，它大大修改的密度和强度的表面碱性位点。结果表明，MgO的加入明显削弱了样品表面的碱性位，并影响了样品在700 ℃甲烷部分氧化反应中的催化性能.在这个意义上，它被发现之间的强碱性位点的不同样品，包括裸露的NiAl 2 O 4，和它们的催化活性的测量密度的良好的相关性。因此，MgO（5 wt.%）/MgO（5 wt. NiAl 2 O 4样品，与镁负载接近的理论单层和最低的强碱性密度的网站，表现出最好的催化性能，在化学计量比（O/C = 1）和非化学计量比（O/C = 0.75）的条件下，在一个相对较长的时间在流。(C)2016爱思唯尔B. V.保留所有权利。
Magnesia modified nickel aluminate spinel catalysts were synthesised and characterised by BET, TEM, XRD, H-2-TPR, XPS, CO2-TPD and TGA-MS techniques. The addition of this promoter induced significant changes in the textural, structural and chemical properties of the resulting spinel derived catalysts. Thus, it enhanced the resistance of the deposited Ni particles against sintering, whereas, upon increasing MgO loading, it drastically modified the density and the strength of the surface basic sites. In fact, an apparent weakening of the surface basic sites with the abundance of highly dispersed Mg species was interestingly observed.The changes provoked by MgO addition deeply influenced the catalytic performance of the prepared samples in the partial oxidation of methane reaction at 700 degrees C. In this sense, it was found a good correlation between the measured density of the Strong basic sites on the different samples, including the bare NiAl2O4, and their catalytic activity. Hence, the MgO(5 wt.%)/NiAl2O4 sample, with a magnesium loading close to the theoretical monolayer and the lowest strong basic density sites, exhibited the best catalytic performance under both stoichiometric (O/C = 1) and non-stoichiometric (O/C = 0.75) conditions during a relatively prolonged time on stream. (C) 2016 Elsevier B.V. All rights reserved.