Elemental and morphological features of thermally modified clinoptilolite as an efficient sorbent for benzo(a)pyrene extraction from water preceding GC – MS analysis

Abstract

Monitoring of benzo(a)pyrene (BaP) levels in water is of great importance because BaP is used as a marker for pollution by other polycyclic aromatic hydrocarbons (PAHs). The elemental and morphological features of clinoptilolite used as a sorbent in dispersive micro-solid phase extraction (D-μ-SPE) of BaP from water samples, before Gas Chromatography – Mass Spectrometry determination (GC – MS) is described. SEM micrographs demonstrated agglomerated particles of Clinoptilolite with no changes in particles, but with increased porosity for Clinoptilolite modified at 300 and 400 oC. The content of elements is lower in thermally modified Clinoptilolite at higher temperatures (300 and 400 oC) than for clinoptilolite treated at 120 oC. After the extraction, EDX analysis of clinoptilolite adsorbed BaP, showed the increased percentage of carbon in the modification prepared at 300 oC, indicating the structure of the applied sorbent is more suitable compared to one treated at 400 oC. Recovery values of surrogate standards demonstrate good extraction efficiency for modification at 300 oC and 400 oC, but cheaper modification (prepared at 300 oC) was selected for BaP analysis.