Ten Commandments for Testing Catalysts

It is beyond the scope of this book to go though all the specifics of catalyst testing and to discuss all pitfalls that may arise. Instead we list the Ten Commandments for the Testing of Catalysts. This is a set of guidelines that have been provided by experts of a company called Catalytica [F.M. Dautzenberg in Characterization of Catalyst Development An Iterative Approach (Eds. S.A. Bradley, M.J. Gattuso, R.J. Ber-tolacini), ACS Symposium Series, Vol. 411 (1989)]. 

Specify objectives What is the purpose of the test Is it for example the specific reactivity and the reaction mechanism, or the long-term industrial use that is of interest  

Use an effective strategy for testing What are the important parameters and how are these determined in the most efficient manner  

Choose the right type of reactor for testing There are quite a number of different reactors. The above-mentioned plug flow reactor and the continuously stirred tank reactor are usually preferred for research laboratory use, but other set-ups may also be of interest for simulating real industrial conditions. 

Establish ideal flow patterns This is usually assumed to be the case for plug-flow and continuously stirred tank reactors, but are all conditions for ideal mixing fulfilled For example, a rule of thumb is that the diameter d of the PFR should be at least lOx the diameter of the catalyst particles to eliminate the influence of the reactor wall. Also, the amount of catalyst should be sufficient to avoid axial gradients. Another rule is that the ratio of the bed length L to the reactor diameter d, i.e. L/d, should be 5-10. Higher values are preferable, but these may cause other problems such as temperature gradients and pressure drops. 

---