In this thesis, high surface area silica aerogel was synthesized by sol-gel method (under ambient pressure drying) an‎d used as adsorbent in dispersive solid phase microextraction method. The chemical structure of silica aerogel was investigated by methods such as Fourier transform infrared spectroscopy, X-ray diffraction, field emission scanning electron microscopy images an‎d elemental mapping. Anthracene an‎d naphthalene from polycyclic aromatic hydrocarbons were selec‎ted as analytes an‎d dispersive solid phase microextraction method was used to identify an‎d measure selec‎ted compounds from polycyclic aromatic hydrocarbons in aqueous samples (in combination with gas chromatography). In order to achieve the highest extraction efficiency an‎d optimization, various effective factors such as the volume an‎d type of desorption solvent, adsorption time, desorption time, salt effect an‎d adsorbent amount were investigated, an‎d the best efficiency was obtained with an adsorbent amount of 65 mg, adsorption an‎d desorption times of 2 an‎d 15 minutes, the solvent type was methanol an‎d the solvent volume was 0.50 ml. A gas chromatography device with a flame ionization detector was used for separation an‎d measurement of analytes. The relative percentage deviation between day an‎d within day was 1.5 an‎d 3.2 percent, the linear range for naphthalene an‎d anthracene was 0.38-1000 an‎d 0.59-1000 μg/L, respectively, an‎d the detection limit was 0.11 an‎d 0.17 μg/L, respectively.

محمد سراجي

محمد تقي جعفري , نفيسه فهيمي كاشاني