Mössbauer spectroscopy in studying industrial catalysts and processes in recycling

Abstract

Advantageous properties of Mössbauer spectroscopy allow the method to be used for the examination of industrial catalysts as well. The method is confined for catalysts containing Mössbauer nuclei (57Fe and 119Sn in most practical cases), on the other side the obtained information is rather unique. Some further limitations emerge in studies for industrial catalysts with this technique in comparison to common catalyst studies, namely the extreme operating conditions, i.e. the elevated temperature and pressure. Thus the in situ conditions for studies cannot be completed easily. To circumvent this difficulty the states of catalysts prior and after the usage can be compared (ex situ conditions). Further, since real catalysts are used for long time period in the industry, their studies can be replaced by accelerated studies performed under ‘conditions relevant to real processes’. Beside catalysis, recycling and reuse of former industrial waste is also an important field for application of the method. A personal selection from reports from recent years on application of the method in representative large scale industrial processes is presented in the overview.