The influence of different fluid inlet types, slits or tubes, on mass trans
fer in a rectangular reactor was studied. Measurements of mass transfer coe
fficients were made using the limiting diffusion current technique based on
ferricyanide ion reduction at a large nickel electrode located downstream
of abrupt expansions. The overall mass transfer coefficients obtained were
3 to 13 times greater than those obtained in fully developed flows. Overall
mass transfer coefficients were correlated for Reynolds numbers ranging fr
om 400 to 3500 by a unique equation by introducing a nondimensional expansi
on factor defined by the ratio of the fluid inlet cross-section to that of
the reactor. The correlation equation obtained was compared with literature
data.