Testing and screening of catalytic materials

For stage 2 testing of eatalytie materials, fixed-bed reactors are used in parallel. The requirements for testing catalytic materials correspond to those for single-reactor operation internal and external heat- and mass-transfer limitations must be excluded during testing to ascertain catalytic results, which are unbiased by transport phenomena. Furthermore, 

Frequently, in evaluating catalyst performance emphasis is put on the selectivity of a desired product and not only on activity. In such cases account should be taken of the fact that selectivity depends on the degree of conversion of the key feed molecules. Under certain circumstances, e.g. selective oxidation of hydrocarbons, the flow conditions can be adjusted in such a way that the degree of oxygen conversion is 1 thus, the selectivity of all the catalysts can be compared. Otherwise it may be advisable to vary the total flow-rate to the multi-channel reactor in this way, selectivity can be obtained as a function of the degree of conversion. Comparable selectivity data for the different catalysts can be 

Note of caution In all catalytic testing experiments the absence of any external and internal transport limitations within the catalyst particle and at its outer surface has to be ascertained otherwise, results regarding activity and selectivity, by which catalytic performance is to be characterized, may not be of any significance. 

Buyevskaya, O.V., Wolf, D. and Baems, M. (2000). Ethylene and propene by oxidative dehydrogenation of ethane and propane Performance of rare-earth oxide-based 

Grubert, G., Kondratenko, E., Kolf, S., Baerns, M., van Geem, P. and Parton, R. (2003). Fundamental insights into the oxidative dehydrogenation of ethane to ethylene over 

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