摘要
工业上常用的许多催化剂是由过渡金属离子担在载体上组成的.在反应过程中,过渡金属离子的价态总是在变化的,ESR的信号也随之变化. 通常认为:能在反应过程中起催化作用的,仅限于催化剂表面的活性中心,而处于催化剂内部的活性中心是不起作用的.在工业上,催化剂的形状和尺寸的设计,主要是从化工动力学、机械强度等工程技术和工艺条件来考虑的.当前,原材料(包括辅助材料,如催化剂等)和能源的消耗指标,在化工产品的成本构成中所占的比重日趋增长,
The first attempt was made to study the distribution map of paramagnetic particles on catalyst by using ESR microscopic imaging technique. Different concentrations of Mo5+ ion on the surface and cross section of catalyst plate arising from different depth of reduction were observed by ESR microscopic imaging. The different distribution maps of V4+ and Mo6+ on the same catalyst were distinguished by ESR microscopic imaging individually. Thus, it is possible to obtain a certain information useful for the design of the dimension and shape of the industrial catalysts.
