
319Heterogeneous Reactors
where k
BL
is the liquid side mass transfer coefcient of B and
k
y
BL
BL
L
=
(4.73)
where D
BL
is the diffusivity of B in the liquid phase.
Reactant A that is dissolved in the liquid at the interphase would be diffusing through
the liquid lm and the ux N
AL
of A in the liquid lm is governed by Fick’s law
ND
dy
AL AL
A
=−
(4.74)
where
D
AL
: diffusivity of A in the liquid phase
C
A
: concentration of A in the liquid lm at a distance y from the interphase
According to lm theory, the mass transfer coefcient k
AL
of A in the liquid phase is
k
y
AL
AL
L
=
(4.75)
Reactant A, while diffusing through the liquid lm, will simultaneously reac