Porous clays heterostructures (PCHs) are a type of clay based porous solids with potentialities in the separation of aromatic molecules by selective adsorption. Mostly PCHs present silica pores, obtained by the polymerization of tetraethoxysilane or silica modified pores by co-polymerization with other types of ethoxysilanes. In the present work we followed an innovative approach to modify the chemical nature of the pores by introducing zirconium oxide species from two different sources. Samples with specific surface areas between 464 and 891 m(2) g(-1) and total pore volumes between 0.249 and 0.636 cm(2) g(-1) were then obtained. The selective adsorption properties of the prepared materials were tested for the separation of binary mixtures of selected aromatic molecules, using a gas-chromatographic method and, in some cases, the samples modified with zirconium presented the more favorable selectivity values. (C) 2012 Elsevier B.V. All rights reserved.