In this work we studied the effects of drying control chemical additive (DCCA's), for instance formamide, N,N-dimethylformamide and propylene carbonate as well as the effect of hydrofluoric acid on structural parameters related to the evaluation of pore connectivity and permeability of sol-gel membranes. In order to study the effect of drying additives, we used a molar ratio additive/alkoxide of 1/1. We used several molar ratios HF/alkoxide to allow an evaluation of the effect of hydrofluoric acid on the textural properties and permeability of the samples. The influence of those parameters on pores interconnectivity and permeability was studied using a combination of geometric modeling and experimental evaluation of the volume fraction of pores (V-v), the surface area density (S-v), the average pore size and bulk density. Using different DCCA's and different concentrations of hydrofluoric acid we obtained membranes with different textural properties and permeability. The elevated interconnectivity of these membranes suggests the feasibility of their utilization in separation and impregnation processes. (C) 2004 Kluwer Academic Publishers.