The three-levels-of-porosity (TLP) reactor is a three-phase reactor suitabl
e for countercurrent trickle-Row. Its packing consists of permeable catalys
t baskets which are arl arranged in the reactor, The volumetric gas-liquid
mass transfer coefficient (k(L)a) was measured as a function of liquid now
for five different TLP configurations. Gas-liquid mass transfer occurs at t
he Faces of the catalyst baskets and at the liquid jets falling from basket
to basket. For the measured configurations, the basket faces contributed t
o only 16% of the overall mass transfer. The mass transfer to the faces of
the baskets is in good agreement with values calculated from theoretical mo
dels. The mass transfer lu the jets is three times higher than predicted by
the penetration theory for stagnant media. This is attributed to small wav
es at the jet surface, internal circulation and entrainment effects for the
jets colliding with the baskets. The TLP reactor has a high freedom in des
ign, which makes it possible to adapt the mass transfer rate to the reactio
n rate of a catalytic process. (C) 2001 Elsevier Science Ltd. All rights re
served.