X-ray photoelectron spectroscopy studies on ethylene oxychlorination catalysts
X-ray photoelectron spectroscopy studies on ethylene oxychlorination catalysts
复制标题
乙烯氧氯化催化剂的X射线光电子能谱研究
DOI：
10.1007/bf02744285
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发表时间：
1987
影响因子：
1.8
通讯作者：
Rieg Ts
中科院分区：
文献类型：
--
作者：
catalystst;R. Vetrivel;K. Seshan;K. R. Krishnamurthy;Rieg Ts
用于乙烯氧氯化反应的氧化铝催化剂上的氯化铜是一个典型的铜处于Cu2+和Cu2+氧化态之间的动态平衡的体系。对氧化还原、结构和组成性质进行了表面研究，以监测催化剂在使用过程中发生的变化，并查明其失活的原因。为此，选择了新鲜催化剂和废催化剂进行表征。在催化剂球的中心形成了以CuAlO2形式存在的以铜+状态的铜的核心。在反应条件下，这种不可逆相的形成破坏了氧化还原平衡。XPS还表明，岩芯中没有钾，它的沉淀是一种新的使用相，可能是由活性成分KCuCl3分解形成的KCl。这些因素促进了失活。
Copper chloride on alumina catalyst used for oxychlorination of ethylene represents a typical system where copper is in a dynamic equilibrium between Cu+and Cu++oxidation states. Surface studies on redox, structural and compositional properties have been undertaken to monitor the changes that occur on the catalyst during use and pinpoint causes for its deactivation. For this, a fresh and a spent catalyst were been chosen for characterization. A core consisting of copper in Cu+state and present as CuAlO2is formed at the centre of the catalyst sphere. Formation of such a nonreversible phase under reaction conditions upsets the redox equilibrium. XPS also shows the absence of potassium in the core and its precipitation as a new phase on use, probably KCl, formed by the decomposition of active component KCuCl3. These factors facilitate deactivation.