Basics
ri= (no. of moles i formed)/(Volume of fluid x time)=(1/V)*(dNi/dt)
rate of reaction definition
(time)-1*(Concentration)1-n
dimensions of the rate constant k for the nth-order reaction
The fluid is perfectly mixed in the radial direction but not mixed at all in the axial direction
Plug flow reactor (PFR)
K ∝ e(-E⁄RT)
Arrhenius law
1. homogeneous reactions
2. heterogeneous reactions
Classification of chemical reactions
there is no direct correspondence between stoichiometry and rate equation
Non-elementary reactions
the contents are well mixed, and there is no flow of materials into or out of the reactor during the reaction
Batch reactor
(sec)-1
1st order rate contant units
the number of molecules involved in an elementary reaction.
Molecularity
we guess a particular form of rate equation and, after appropriate integration and mathematical manipulation, predict that the plot of a certain concentration function versus time should yield a straight line. The data are plotted, and if a reasonably good straight line is obtained, then the rate equation is said to satisfactorily fit the data.
Integral method to analyzing kinetic data
the output composition is identical to the composition of the material inside the reactor, which is a function of residence time and rate of reaction.
continuous stirred tank reactor (CSTR) or mixed flow reactor (MFR)
(sec)-1*(mol/lit)
Zero order rate constant units
Oxidation of SO2 to SO3
example for heterogeneous catalytic reaction
This method can be used to develop or build up a rate equation to fit the data
differential method
constant-density reaction system
Constant volume reactor
K ∝ T e(-E⁄RT)
Transition theory
the sum of the powers of concentrations terms in the rate expression
Order of reaction
fraction of reactant reacted away
conversion (XA)
(moles of A reacted)/(Initial moles of A)
conversion (XA)
K ∝ T1/2 e(-E⁄RT)
Collision theory