DRIFT study of CO chemisorption on organometallics-derived Pd/MgO catalysts: the effect of chlorine
DRIFT study of CO chemisorption on organometallics-derived Pd/MgO catalysts: the effect of chlorine
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有机金属衍生的 Pd/MgO 催化剂上 CO 化学吸附的 DRIFT 研究：氯的影响
DOI：
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发表时间：
1996
期刊：
影响因子：
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通讯作者：
A. Fusi
中科院分区：
文献类型：
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作者：
M. Kappers;C. Dossi;R. Psaro;S. Recchia;A. Fusi
采用化学气相沉积[Pd(C3H5)(C5H5)]和浸渍[Pd(C3H5)Cl]2和[Pd(Acac)2]的方法制备了氧化镁负载钯催化剂。CO吸附在预还原态催化剂上的漂移光谱表明，金属粒子的电子态与制备方法有关，与金属有机前驱体密切相关。在500℃的正庚烷重整反应中，以CVD为基础的体系表现出最高的活性和选择性。来自浸渍溶剂的氯离子与表面羟基交换。这样就形成了酸性的镁氯中心，从而对催化剂的性能产生了有利的影响。当使用含氯前驱体时，由于化学吸附的氯原子部分覆盖了钯表面，重整活性崩溃。
Magnesia-supported palladium catalysts were prepared from chemical vapour deposition (CVD) of [Pd(C3H5)(C5H5)] and incipient wetness impregnation of [Pd(C3H5)Cl]2 and [Pd(acac)2]. DRIFT spectroscopy of adsorbed CO on prereduced catalysts indicates that the electronic state of metal particles depends on the preparation methodology and markedly on the organometallic precursor. Inn-heptane reforming at 500°C, the highest activity and selectivity were shown by the CVD-based system. Chloride ions deriving from the impregnation solvent exchange with surface hydroxyls. Acidic Mg-Cl sites are thus formed, which induce a beneficial effect on the catalytic properties. The reforming activity collapsed when a chlorine-containing precursor was used, due to a partial coverage of the palladium surface with chemisorbed chlorine atoms.