Comparison of BEA, USY and ZSM-5 for the quantitative extraction of polycyclic aromatic hydrocarbons from water samples

The physicochemical properties of three commercial zeolites – namely BEA, USY and ZSM-5 – are compared for the water removal of 15 PAHs included in the US EPA priority pollutants list. The best percentages of extraction were obtained with BEA and varied from 85.2 ± 1.7% (benzo[g,h,i]perylene) to 99.6 ± 1.1% (pyrene). The correlation of physicochemical properties to the percentages of extraction suggests that the predominant factor for a successful extracting performance is the adsorption of PAHs to the external surface of the extracting material. This process is facilitated by relatively large total pore volumes, large average pore diameters and a homogeneous distribution of Lewis acid sites. The presence of the latter enhances extraction performance via π-electron interactions with the aromatic rings of the PAH.

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► Zeolites were compared for water removal of polycyclic aromatic hydrocarbons.
► Compound extraction mainly occurs via adsorption to zeolite external surface.
► Adsorption is facilitated by large total pore volumes and average pore diameters.
► Adsorption is favored by a homogeneous distribution of acid Lewis sites.
► Acid Lewis sites enhance adsorption via π-electron interactions with compounds.