Porous polysilsesquioxanes for the adsorption of phenols.

Arylene- and ethylene-bridged polysilsesquioxane materials have been synthesized by the hydrolysis and condensation of alkoxysilyl precursors under basic conditions. Cetyltrimethylammonium chloride was used to increase the porosity and surface areas of these materials via the surfactanttemplate approach. Structural characterization of these materials was carried out by nitrogen gas sorption and X-ray diffraction. The adsorption of three phenolic compounds (4-nitrophenol, 4-chlorophenol, 4-methylphenol) has been investigated by both batch and column testing. The arylene-bridged material exhibited a much greater affinity for all three phenols. The efficient removal of adsorbed phenols by a simple ethanol wash led to sorbent regeneration and separation of the aromatic species.