Multiple Reactions and Selectivity: Screencasts
Describes the effects of concentration, temperature, catalyst, and reactor type on selectivity for parallel reactions.
We suggest you list the important points in this screencast as a way to increase retention.
Describes the effect of reaction time on selectivity for a series reaction.
We suggest you list the important points in this screencast as a way to increase retention.
Important Equations:
\[S_D = \frac{r_D}{r_U}\]
where \(S_D\) = instantaneous selectivity (dimensionless)
\(r_D\) = rate of desired reaction (mol/(L s))
\(r_U\) = rate of undesired reaction (mol/(L s))
\[\tilde{S_D} = \frac{F_D}{F_U}\]
where \(\tilde{S_D}\) = overall selectivity for a flow reactor (dimensionless)
\(F_D\) = molar flow rate of desired product (mol/s)
\(F_U\) = molar flow rate of undesired product (mol/s)
\[\tilde{S_D} = \frac{N_D}{N_U}\]
where \(\tilde{S_D}\) = overall selectivity for a batch reactor (dimensionless)
\(N_D\) = number of moles of desired product (mol)
\(N_U\) = number of moles of undesired product (mol)
Note that selectivity definitions are not universal, and different textbooks use different definitions.