Empty volume of recycle reactors

Evaluations of the measurements are based on the transient material balance equation for CSTR  

The small volumes of the feed line from the switching valve to the reactor and the discharge line to the analyzer can be corrected for, since they will have plug flow. This will only displace the zero time on the recorder and it can be easily corrected. 

Multiples of Residence Time Fraction of Inlet Concentration 

The previous volume measurement was done by methane because this does not react and does not even adsorb on the catalyst. If it did, the additional adsorbed quantity would make the volume look larger. This is the basis for measurement of chemisorption. In this experiment pure methane flow is replaced (at t = 0) with methane that contains C = Co hydrogen. The hydrogen content of the reactor volume—and with it the discharge hydrogen concentration— increases over time. At time t - t2 the hydrogen concentration is C = C2. The calculation used before will apply here, but the total calculated volume now includes the chemisorbed quantity. 

As can be seen on the figure in Appendix F, if the adsorbed volume is 25% more than the reactor volume, a good measurement is possible. At a dimensionless time of 0 = 2.0, the discharge concentration is 10% lower when adsorption occurs. For a reactor volume of 1000 cm the adsorbed volume is 250 cm, which is 250/22412 = 0.011 mol. This much has to be adsorbed on 80 cm = 50 g of catalyst, and this is 0.011/0.05 = 0.22 mol/kg. 

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