Porous clay heterostructures with zirconium for the separation of hydrocarbon mixtures

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 m2 g−1 and total pore volumes between 0.249 and 0.636 cm2 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.

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► We prepared porous materials from clays by a gallery templated method.
► Composition of pores was changed from silica to silica doped with zirconium oxide.
► The separation of hydrocarbon mixtures was evaluated by a chromatographic method.
► The best separation was obtained in samples doped with zirconium oxide.
► Separation results were dependent on the source of zirconium oxide.