Which reactor?

As a 'pure chemist' you might prefer the STR for such a 'normal' reaction. That is not bad, as long as the reaction is not too fast for your sensing device and when you are willing to carry out some additional evaluation work: you get the concentration/time curve and can calculate directly the conversion, but for the reaction rate you have to do a graphical or numerical differentiation of the C(t) curve. You know the rest of the evaluation: plot ln r versus ln c and get the order as ascent and ln k as Y-intersection. For fast reactions you are advised to take a TFR: 'Continuous Flow Method'. But as a chemist with reaction engineering knowledge you should prefer a CSTR for the 'normal' case, mainly when very much measurements have to be carried out and much data is to be acquired. Why ? From the reactor equation:

t_R = tau = C_A,0(U/-r)

follows: -r = C_A,0(U/tau)
and with the definition of the conversion we get:

-r = (C_A,0- C_stat) /tau

this means that we are measuring the reaction rate more or less 'directly' with the stationary concentration of educt A in the CSTR. The rest of the kinetic evaluation is as usual (see my task as an example). And here we have also some 'connection' to the differential loop reactor: if you operate this reactor with high recirculation rates, the reactor can be calculated with the CSTR-balance. This brings forth the same ease of getting directly the reaction rate, - that is very practical for heterogeneous (catalytic) reactions, as in this case you have to regard much more 'additional effects' like for instance catalyst deactivation behaviour and mass transfer (liquid film and pore diffusion) etc.

By the way: it is also important to realize that the thermal conduction of the process (see e.g. an overview) is much more easy in the CSTR than in the other reactor types, you can operate the reactor much more precisly isothermal than the others.

The only disadvantage of the continuous reactors is that you need 'by far' more chemicals as in the case of the batch.

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