This work presents a detailed study of mass transfer in gas-liquid-solid ceramic membrane contactors. For steady-state mass transfer investigations and determination of bubble-point pressure, a bench-scale low-pressure unit has been constructed for the examination of membrane contactors of various lengths. On the contrary to expectations, very low bubble-point pressure values of investigated membrane contactors were obtained, which is attributed to the presence of irregularities in the membrane wall. For the investigated range of temperatures and transmembrane pressure differences, Wilke-Chang equation provides a very good estimation for the permeance of various model compounds through the membrane wall. Rather low liquid-liquid (L-L) and gas-liquid (G-L) mass transfer rates per unit surface area of ceramic membrane tube, being in the range of 10(-5) Mol m(-2)s(-1), were further measured either for organic compounds dissolved in water or gases. This alludes that a gas-liquid-solid membrane contactor with a high geometric surface area should be developed in order to efficiently conduct a heterogeneously catalyzed reaction in this three-phase reactor system. (C) 2003 Elsevier Science B.V. All rights reserved.